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BIOL 102- Dr. Terry Spohn
Chapter one pt 1
Chemistry - the study of matter and the energy used to change it
Matter- anything that has mass and volume
-Composed of elements
Elements- cannot be simplified
periodic table- lists all known elements
Atoms- smallest functional unit of elements
- Nucleus (central core)
o Protons
Have a positive charge
Have mass
o Neutrons
No charge
Have mass
- Shells (surrounding nucleus)
o Electrons
Negative charge
No discernable mass
- Colossians 1:17 explains why atoms are able to stay together while repelling
themselves
- Atomic symbol- one or 2 letters
- Atomic number- number of protons (and electrons before a reaction)
- Atomic mass- roughly equal to protons + neutrons
- In an electrically neutral atom, number of protons = number of electrons
o First shell- 2 electrons
o Second shell- eight electrons
o Third shell- eighteen electrons
o To be electronically stable, there has to be 18 on the outer shell or 8
- Isotopes have a different number of neutrons
o Same atomic number (same number of protons)
o Different atomic mass (different number of neutrons)
o Unstable isotopes are called radioisotopes
o Radioisotopes give off
Energy (in the form of radiation)
Particles
- Some radio isotopes have scientific and medical uses
o Carbon 14 used for dating fossils
o Diagnostic imaging
o Cancer treatment
o Power supply for implants such as cardiac pacemakers
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BIOL 102 Notes PT 3
Dr. Terry Spohn-Liberty University
The importance of Hydrogen Ions:
Acids
o Donate H ions (protons)
o Increase H ion concentration in solutions
Bases
o Accept H ions
o Lower H ion concentration in solution
pH scale
o a measure of hydrogen ion concentration
o acids have a pH less than 7
o bases have a pH greater than 7
Buffers
minimize pH change
help maintain stable pH in body fluids
carbonic acid and bicarbonate act as one of the body’s most important buffer pairs
weak acids stay in water
Organic Molecules of Living Organisms
carbon- the building block if living things
o comprises 18% of the body by weight
can form 4 covalent bonds
can form single or double bonds
can build micro or macromolecules
Macromolecules are synthesized and broken down in the cell
dehydration synthesis
o removes equivalent of a water molecule to link molecular units
o requires energy
o builds macromolecules from smaller subunits
Hydrolysis
o Adds the equivalent of a water molecule to break apart macromolecules
o Releases energy
Dehydration synthesis is the reverse of hydrolysis
Carbohydrates: used for energy and structural support
Monosaccharides: simple sugars
o Glucose
o Fructose
o Galactose
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o Ribose
o Deoxyribose
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BIOL 102- Dr. Spohn Liberty University
Chapter 1 pt 2
Energy- the capacity to do work
Potential energy- stored energy
Kinetic energy- energy in motion, energy doing work
Electrons have potential energy
o Each shell corresponds to a specific level of potential energy
o Shells further from the nucleus contain electrons with more potential energy
Atoms are more stable when the outer shell is full
Atoms will interact with other shells to fill outer shell
Chemical bonds link atoms to form molecules
o Chemical bonds- attractive forces holding atoms together
o Kinds of chemical bonds
Covalent bonds
Ionic bonds
Hydrogen bonds
o Strength of a bond determined by amount of energy it takes to break it
Molecule- 2 or more atoms chemically bonded together
Compound- 2 or more different atoms chemically bonded together
Covalent bonds form when atoms share electrons
o Very strong bonds
o H2, O2, H2O
Nonpolar covalent bonds- electrons shared equally
Polar covalent bonds- electrons not shared equally
Ionic bonds
o Ion- an electrically charged atom or molecule
o Positively charged ion forms if an electron is lost
o Negatively charged ion forms if an electron is gained
o Ionic bond- attractive force between oppositely charged ions
Hydrogen bonds
o Form between polar molecules
o Polar molecules:
Contain polar covalent bonds in which there is unequal sharing of
electrons
Electrically neutral overall, but uneven charge distribution
o Hydrogen bonds
Weak attraction between oppositely charged regions of polar molecules
Ex. Weak forces between water molecules
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Life depends on water
Water is polar
Water is liquid at water temperature
Water can absorb and hold heat energy
Water is a biological solvent
Water helps regulate body temperature
Solvent- the liquid in which other substances are dissolved
Solute- any dissolved substance
Hydrophilic- polar molecules attracted to water and interacts easily with water
Hydrophobic- nonpolar molecules (neutral) that do not interact or dissolve in water
All membranes are made of hydrophobic lipids.
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BIOL 102 Notes PT 4
Dr. Terry Spohn-Liberty University
Oligosaccharides
More than one monosaccharide linked together
Disaccharides: two monosaccharides linked together
o Sucrose: glucose and fructose
o Maltose: glucose and glucose
o Lactose: glucose and galactose
Polysaccharides store energy
Polysaccharides-thousands of monosaccharides joined in chains and branches
o Starch-made in plants; stores energy
o Glycogen-made in animals; stores energy
o Cellulose- indigestible polysaccharide made in plants for structural support
Lipids
3 important classes of lipids
o triglycerides- energy storage molecules
o phospholipids- cell membrane structure
o steroids- carbon-based ring structure
2x more energy can be stored in 1g of fat than any other organic molecule
Triglycerides- known as fat and oils
composed of glycerol and 3 fatty acids
o fatty acids
saturated (in fats)
unsaturated (in oils)
o stored in adipose tissue
o energy storage molecules
Phospolipids
structure
o glycerol and 2 fatty acids and phosphate group
o one end of molecule is water soluble (hydrophilic)
o other end of molecule is water insoluble (hydrophobic)
Function
o Primary component of cell membrane
Steroids
Structure
o 4 carbon rings
examples:
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o cholesterol- a major membrane stabilizer
o hormones
Proteins
long chains (polymers) of subunits called amino acids
amino acid
o 20 different types
o amino end, carboxyl end, R group
amino acids are joined by peptide bonds, which are produced by dehydration synthesis
reactions
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BIOL 102 Notes PT 5
Dr. Terry Spohn-Liberty University
Structure of RNA
Single-stranded
Nucleotides contain
o Ribose
o Nitrogenous bases (adenine, guanine, cytosine, uracil)
Nucleic Acid function
DNA- instructions for making RNA
RNA- instructions for making proteins
Proteins- directs most of life’s processes
DNA to RNA to protein
ATP Carries energy
Structure and function of adenosine
o Nucleotide- adenosine triphosphate
o Universal energy source
o Bonds between phosphate groups contain potential energy
o Breaking the bonds releases energy
ATP to ADP to Potential energy
CHAPTER 3: Structure and function of cells
Cell Doctrine
All living things are composed of cells
A single cell is the smallest unit that exhibits all the characteristics of life
All cells come from only preexisting cells
Two basic cell types classified by internal organization
Prokaryotic cells
o Plasma membrane
o No nucleus
o Cytoplasm: fluid within membrane
o No true organelles
Eukaryotic Cells
Plasma membrane
Nucleus- information center
Cytoplasm- fluid within membrane
Organelles- structures with special functions
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All humans have eukaryotic cells
Cell structure reflects cell function
Though eukaryotic cells are remarkably similar, there are structural differences
o Examples
Muscle cells
Contain numerous organelles providing energy needed for muscle
contraction
Nerve cells
Long and thin to carry impulses over distance
o Small size is efficient
Everything we know about cells come from microscopy and biochemistry
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BIOL 102 Notes PT 5
Dr. Terry Spohn-Liberty University
Denaturation:
Permanent dehydration of protein structure
o Can be caused by temperature changes or pH or heavy metal ions
Leads to loss of biological function
Enzymes:
Are proteins
Function as biological catalysts
o Speed up chemical reactions
o Are not altered or consumed by the reaction
Without enzymes, many biochemical reactions would not proceed quickly enough to
sustain life
The functional shape of an enzyme is dependent on:
o Temperature
o pH
o Ion concentration
o Presence of inhibitors
Nucleic Acids:
Two types
o DNA: deoxyribonucleic acid
o RNA: ribonucleic acid
Functions
o Store genetic information
o Provide information used in making proteins
Nucleic acids are long chains containing subunits known as nucleotides
Nucleotides- building blocks
Each nucleic acid contains:
o 5 carbon sugar
o DNA nucleotides: deoxyribose
o RNA nucleotides: ribose
Nitrogenous base
Phosphate group
Structure of DNA
Double stranded
Nucleotides contain:
o Deoxyribose (sugar)
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o Nitrogenous bases
Adenine
Guanine
Cytosine
Thyamine
Pairing
o Adenine-thyamine
o Guanine-cytosine
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BIOL 102 Notes PT 5
Dr. Terry Spohn-Liberty University
Cells Remain small to be efficient
Small cells have a higher surface to volume ratio
High surface to volume ratio promotes efficiency in:
o Acquisition of nutrients
o Disposal of wastes
Plasma Membrane Surrounds the cell
Seperates a cell from its environment
Selectively permeable
o Permits movement of some molecules out of the cell, but blocks others
Enables transfer of substances between environment and cells
Plasma membrane is a lipid bilayer
o Phospholipids- polar head and nonpolar tail
o Cholesterol- makes membrane more rigid
o Proteins- transport through membrane
o Carbohydrates- recognition patterns for cell and organisms
o Non-rigid
o Fluid mosaic
Molecules cross the plasma membrane in several ways
Passive transport
o Cell does not need to expand energy for this
Diffusion
Osmosis
Active transport
o Cell must expand energy (ATP)
Bulk transport
o Involves membranious vesicels to move larger substances
Endocytosis
exocytosis
Passive transport moves with the concentration gradient
passive transport is powered by the concentration gradient. In the cell it occurs as:
o diffusion through lipid layer
o diffusion through protein channels
o facilitated transport
carrier proteins assist in moving molecules across the membrane, down
the concentration gradient
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Active Transport
moves substances from an area of low concentration to an area of higher concentration
o requires a membrane protein (transporter)
o requires ATP or other energy source
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BIOL 102 Notes
Dr. Terry Spohn-Liberty University
Isotonic Extracellular Fluid maintains cell volume
Tonicity
o Always comparing 2 compartments at the same time (fluids)
o Relative concentrations of solutes in 2 fluids
Isotonic
o Extracellular and intracellular ionic concentrations are equal
o Cells maintain a normal volume in isotonic extracellular fluids
o Regulatory mechanisms maintain extracellular fluid (fluid that is
isotonic with intracellular fluid)
Variations in tonicity
o Hypertonic: “crenate”- shrink to the point of death
Extracellular ionic concentration higher than intracellular ionic
concentration
Water will diffuse out of cell
Cell will shrink and die
o Hypotonic: “plasmolyse”- to destroy the cytoplasm
Extracellular ionic concentration lower than intracellular ionic
concentration
Water will diffuse into cell
Cell may swell and burst
Chapter Three Part B:
Nucleus
Functions
o Contains the genetic information of the cell
o Controls the cell
Structural features
o Double layered nuclear membrane
o Nuclear pores
o Chromosomes/chromatin
o Nucleolus (means little nucleus, contains DNA)- codes for ribosomes
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Ribosomes
Site of protein synthesis
Location
o Free- floating in cytoplasm
o Bound- attached to outer surface of endoplasmic reticulum
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BIOL 102 Notes
Dr. Terry Spohn-Liberty University
Bulk Transport
Involves membranous vesicles to move larger substances
o Endocytosis
o Exocytosis
Passive Transport moves with the concentration gradient
Passive transport is powered by the concentration gradient. In the cell it occurs
as:
o Diffusion through lipid layer
o Diffusion through protein channels
o Facilitated transport
Carrier proteins assist in moving molecules across the membrane,
down the concentration gradient
Active Transport
Moves substances from an area of lower concentration to an area of higher
concentration
o Requires a membrane protein (transporter)
o Requires ATP or other energy source
Endocytosis and Exocytosis move materials in Bulk
Used to move larger molecules
o Endocytosis: brings substances into the cell
o Exocytosis: expels substances from the cell
Information transfer across the plasma membrane
Receptor proteins span membrane
o Required for transmission of information to and from cell
Receptor cites (ion receptor proteins)
o Interact specifically with signal molecules
A charge is triggered within the cell as a result of a binding signal molecule to
receptor site
Different cell types have different receptor proteins
The sodium-potassium pump: helps maintain cell volume
Sodium-potassium pump expels unwanted ions, keeps needed ones, maintains
cell volume
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ATP is utilized to get rid of three sodium ions for every two potassium ions within
the cell
Increase in cell volume equals increase in water in cytoplasm by decreasing
pumping and allowing more sodium inside cell
Decrease in cell volume equals less water in cytoplasm by increasing pumping
and expelling more sodium ions
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BIOL 102 Notes
Dr. Terry Spohn-Liberty University
Endoplasmic Reticulum (ER)
Two types
o Rough ER
Has ribosomes on surface
Protein manufacturing
o Smooth ER
No ribosomes on surface
Lipid synthesis
Packages the proteins
Golgi Apparatus
Refines synthesized products
Packaging and shipping center
Products are packages into vesicles and shipped to other locations within the cell or to
the cell membrane for export
Vesicles
Storage and shipping vesicles
Secretory vesicles
Endocytic vesicles
Peroxisomes
o Contain enzymes that detoxify
Lysosomes
o Contain digestive enzymes (very powerful ensymes)
Mitochondria
“power plant” of the cell
surrounded by a double membrane
utilizes O2 and produces CO2
generates ATP
Fat and Glycogen: Sources of Energy
fat
o triglycerides
o long term energy storage in animals
Glycogen
o Carbohydrate storage
o Short term energy storage in animals
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Cell Structures for Support and movement
Cytoskeleton
o Microtubules
o Microfilaments
Cilia
o Short, many
o Found on cells lining airways
Flagella
o Long, single
o Enable spermatozoa to swim
Centrioles
o Cell division
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Liberty University
BIOL 102- Dr. Spohn
Specialized Connective tissues serve special functions
Cartilage: produced by chondroblasts found in lacunae
o No blood vessels
o High collogen content
Bone: inorganic matrix with calcium salts for hardness
Blood: fluid matrix of plasma, red blood cells, white blood cells and platelets
Adipose tissue: fat cells; function in insulation, protection and energy storage
Cartilage Types
Hyaline- at the end of long bones at the joints (reduces friction)
Fibrocartilage- found between the vertebrae in the spinal column
Elastic- found only in ears, very flexible
Muscle tissue contracts to produce movement
Skeletal muscle (striated muscle)
o Moves body parts
o Voluntary mulcinucleated
Cardiac muscle
o Functions in the heart
o Involuntary, single nucleus
o Produce ATP faster than it uses it, never tires
Nervous Tissues transmit impulses
Neuron- specialized nervous system cell
o Produce and transmit impulses
o Structural components: cell body, dendrites, axon
Glial cells support neurons
Organs and Organ systems perform complex functions
Organs
o Contain two or more tissue types joined together
o Perform specific funcitons
Organ Systems
o Groups of organs that perform a common function
o Ex. Digestive system: mouth, throat, stomach, intestines, and liver
Tissue Membranes
Serous membrane
o Reduces friction between organs
Mucous membrane
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o Lubricates surface
o Captures debris
Synovial membrane
o Lines spaces in movable joints
Cutaneous membrane
o The skin
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BIOL 102 Notes
Dr. Terry Spohn-Liberty University
Cells use and transform matter and energy
Metabolism
o The sum total of all the chemical reactions in a cell or organism
Anabolism
o Requires energy
o Used in making/assembling large molecules
o May require energy (ATP)
o Used in building and assembling cell components
o Used in storing energy
Catabolism
o Requires enzymes
o Breakdown of molecules
o May release energy
o Used in breaking down nutrients and recycling cell components
o Used to access energy storage
Glucose provides the cell with energy
Glucose provides energy for the cell
Energy in glucose is used to generate ATP
In absence of glucose, other carbohydrates, fats, and proteins, glucose can
be catabolized
Cellular Respiration-Makes ATP
I. Glycolysis (occurs in cytoplasm) [does not require oxygen- anaerobic
glycolysis]
a. Glucose molecule to two 3 carbon compounds
i. Pyruvate molecules
1. +4 ATP molecules (net gain of 2 ATP)
II. Citric acid Cycle (Kreb’s Cycle)
a. Occurs in the mitochondria
b. You get 2 ATP and high energy electrons associated with NADH and
FADH2
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III. Electron transport System
a. Occurs in the mitochondria
b. Get 32 ATP
c. Requires O2
IV. Other energy sources
a. Glycogen
b. Fats
i. Triglycerides have twice the energy of carbohydrates
c. Proteins
i. Same energy content as carbohydrates
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BIOL 102 Notes
Dr. Terry Spohn-Liberty University
Chapter Four
Tissues
Groups of cells with a common function
Four primary tissues
o Epithelial
o Connective
o Muscle
o Nervous
Epithelial Tissues
Line body cavities and cover surfaces
Glandular epithelia
o Epithelial cells adapted to make up glands
o Exocrine glands
Secrete into ducts to exterior of body
o Endocrine glands
Secrete into the blood to carry chemical messages throughout
the body
Mostly cells, very little matrix
Cells are tightly joined
Epithelial Shape Classification
Shape
o Squamous
Flattened cells
Line vessels, part of lungs, body surface
Easily facilitates diffusion
o Cuboidal
Form lining of tubules, glandular tissue
o Columnar
Line respiratory, digestive, reproductive tracts
Number of layers
o Simple/single layered
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Adapted for diffusion across cell barriers
Line glands and respiratory, digestive, reproductive tracts
o Stratified/multi-layered
Provide protection, as in the skin surface
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BIOL 102 Notes
Dr. Terry Spohn-Liberty University
Basement Membrane:
Provides structural support to overlying cells
Attaches epithelial layer to underlying tissues
Junctions- hold epithelial cells together
o Tight junctions
o Nothing passes
Adhesion junctions/spot desmosomes
o Some movement between cells
Gap junctions
o Protein channels
Connective Tissues
Cells scattered in a matrix, mostly matrix in the tissues
The nature of the matrix gives characteristics of the connective tissues
General functions
o Supports softer organs of the body
o Connects parts of the body
o Stores fat
o Produces blood cells
Contains cells embedded in nonliving extracellular matrix
Matrix provides the strength
Two general types
o Fibrous
o Special
Fibrous Connective tissues
Function-provides strength and elactisity
Contains fibers and cells embedded in gel like ground substance (matrix)
Matrix- intercellular material giving the CT its characteristics
Cells- fibroblasts, macrophages, lymphocytes, and neutrophils
Fibers: collagen, elastic, and reticular
4 general types
o loose-surrounds many organs, lines cavities around blood vessels
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o dense, forms tendons, ligaments, deeper layers of skin
(tendons=muscle to bone, ligament=bone to bone)
o elastic- surrounds stomach and bladder, maintains shape
o reticular-makes up internal framework of soft organs (liver) and the
lymphatic system
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Bio 102- Liberty University
Chapter 5
Cartilage and Joints
Cartilage
o Function- support
o Types
Fibrocartilage
Hyaline
Elastic cartilage
Ligaments
o Function: attach bone to bone
o Dense fibrous connective tissue
Bone Development
Early fetal development: cartilage model
o Formed by chondroblasts (cartilage forming cells)
Later fetal development: osteoblasts replace cartilage with bone
Childhood: primary and secondary ossification sites formed
Adolescence: elongation of growth plates
Hormonal Control of Bone Growth
Preadolescence
o Growth Hormone stimulates bone lengthening
Early-adolescence
o Estrogen and testosterone stimulate bone lengthening
Late-adolescence
o Estrogen and testosterone cause replacement of cartilage growth plates with
bone
Cells involved in the development
Chondroblasts- cartilage forming cells
Osteoblasts- young bone-forming cells
Osteocytes- mature bone cells
Osteoclasts- bone-dissolving cells
Mature Bone Remolding and Repair
Changes in shape, size and strength
o Dependent on:
Diet
exercise
age
Bone cells regulated by hormones
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o Parathyroid hormone (PTH, osteoblasts)-removes calcium from bone
o Calcitonin- adds calcium to bone
Repair
o hematoma
o callus formation
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Bio 102- Liberty University
Chapter 5
Human Skeleton
206 Bones
Axial Skeleton
o Skull
o vertebral column
o sternum
Appendicular Skeleton
o Pectoral girdle
o Pelvic girdle
o Limbs
Spine
o 7 Cervical vertebrae
o 12 thoracic vertebrae
o 5 lumbar vertebrae
o 5 sacrum (fused)
o 4 coccyx (fused)
Vertebral Column
Regions
o Cervical
o Thoracic
o Lumbar
o Sacral
o Coccygeal
Intervertebral disks: cushion vertebrae; assist in movement and flexibility
Ribs
o 12 pairs
o bottom 2 pairs are floating
Sternum- breastbone
o 3 bones fused together
Appendicular Skeleton
Pectoral Girdle
o Clavicle and scapulae
Pelvic Girdle
o Coccyx bones, sacrum, pubic symphysis
Limbs
o Arms
Humerus
Radius
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Ulna
Wrist and hand bones
o Legs
Femur
Tibia
Fibula
Ankle and foot bones
Joints (Articulations)
Classified by degree of movement
o Fibrous joint: Immovable (skull)
o Cartilaginous joint: slightly movable, cartilage connection (backbone)
o Synovial joint: freely movable
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Bio 102- Liberty University
Chapter 5
Synovial Joints
Joint capsule
o synovial membrane and hyaline cartilage
Synovial membrane secretes synovial fluid as a lubricant
Hyaline cartilage acts as a cushion
Types of synovial joints
o Hinge joint
o Ball and socket joint
Tendons- connect bone to muscle
Diseases and disorders of the Skeletal system:
Sprains
o Stretched or torn ligaments
Bursitis
o Inflammation (tendonitis)
Arthritis
o Inflammation of joints
Osteoarthritis
Rheumatoid arthritis
o Osteoporosis
Excessive bone loss
Muscular System- Chapter 6
Muscle Function: Produce movement or generate tension
Principle function
o Contraction
Shortens distance between bones
o Skeletal muscle moves bones
Muscle groups
o Synergistic
groups work together
o Antagonistic
groups oppose each other
Muscle structure
Fascicle
o Bundles of muscle fibers wrapped with connective tissue (fascia)
Muscle fibers (muscle cell)
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o Long tube shaped
o Multinucleated
o Packed with myofibrils
Myofibrils contain
Actin
myosin
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Bio 102- Liberty University
Chapter 6
Activity of Muscles Can Vary
Isotonic contractions
o muscle shortens
o movement occurs
Isometric contractions
o muscle doesn’t shorten
o no movement
Degree of nerve activation influences force
Terms to know
o Motor unit
Motor neuron and all the muscle cells that it controls
o Muscle tension
Mechanical force that muscles generate when they contract
Determined by
Motor unit size
Number of active motor units
Frequency of stimulation of motor units
o All-or-none principle
Individual muscle cells are completely contracting or are relaxed
o Muscle tone
Whole muscles maintain intermediate level of force known as muscle
tone
o Recruitment
Activation of additional motor units when needed- this increased muscle
tone
Muscle Twitch
Complete cycle of contraction-relaxation in response to stimulus
Can be observed using a myogram (laboratory recording of muscle activity)
Phases:
o Latent period
o Contraction
o Relaxation
o Summation
o Tetanic contraction
Muscle Activity
Two types of muscle fibers
o Slow twitch: endurance, long duration contraction, contain myoglobin
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Jogging
Swimming
biking
o Fast twitch: strength, white muscle, short duration contraction
Sprinting
weight lifting
tennis
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Human Biology
Katelin Bibbo
04/14/2017
Chapter 12: Class Notes
Regulating The Amount Of Light And Focusing The Image
Regulating light
o Iris: opens and closes to control amount of light entering the eye
Focusing
o Includes bending of light by cornea and lens
Accommodation
o Adjustment of lens curvature to enable focusing on near and far objects
o Made possible by ciliary muscle
Eyeball Shape Affects Focus
Normal shape allows focusing on the retina
Myopia: nearsighted
o Eye longer than normal
o Distant objects focus in front of retina
o Corrected with concave lenses
Hyperopia: farsighted
o Eye shorter than normal
o Near objects focus behind the retina
o Corrected with convex lenses
Astigmatism:
o Irregularities in cornea or lens
o Corrected with specially ground lenses that compensate for lens irregularities
Rods And Cones(Color) Respond To Light
Photoreceptors
o Rods and cones
Response to light: photo-pigment (protein) changes shape
Rods: approx. 120 million
Cones: approx. 6 million
o 1 million ganglion cells
o significant amount of convergence and summation
Rods provide vision in dim light
Rhodopsin: photo-pigment within rods
o More sensitive to light than the photo-pigment in cones
In dim light, vision primarily dependent on rods
Rods do not enable color vision
The farther from the fovea, the greater the density of rods
Cones provide color vision and accurate images
Three types of cones enable color vision
o Red, blue, green
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Human Biology
Katelin Bibbo
04/14/2017
Brain interprets rations of impulses coming from ganglion cells connected to the three
kinds of cones
Cones require stronger light to be activated
Cone responsible for visual acuity
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BIOL 102 Notes
Liberty University- Dr. Spohn
Chapter 11: The Nervous System
Nervous System has two principal parts
•
Central nervous system (CNS)
o Components: brain and spinal cord
o Functions: receives, processes, and transfers information
•
Peripheral nervous system (PNS)
o Components: nerves outside CNS
o Sensory division: carries information toward the CNS
o Motor division: carries information away from CNS
•
Figure 11.1 in text book
o Parasympathetic nervous system controls body when there is low stress
o Sympathetic nervous system: fight or flight side
Neurons: communication cells for the nervous system
•
Neurons are specialized cells for communication
o Generate and conduct electrical impulses
•
Types of neurons
o Sensory neurons: neurons found in the PNS that receive stimuli and transmit
information to the CNS
o Interneurons: transmit information between components of the CNS
o Motor neurons: neurons found in the PNS that transmit information away from
the CNS
Neurons: Cell structure
•
Three parts of the neuron
o Cell body: main part of the cell, has the nucleus and most of the cytoplasm and
organelles
o Dendrites: small slender extensions of the cell body, receive incoming
information
o Axon: long slender extension, specialized to conduct electrical impulses away
from the cell body
•
Neurons rarely become cancerous, but the support cells surrounding the neurons can
Neurons initiate action potentials
•
Neurons generate and transmit action potentials
•
An action potential is basically an electrical impulse
•
Primary means of communication throughout the nervous system
•
Most headaches are caused by pain nerves that are signaled because the blood vessels
surrounding them are not receiving enough oxygen
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Sodium-potassium pump maintains resting potential
•
Functions of the na/k pump
o Maintains cell volume
o Establish and maintain resting potential (voltage) by active transport of Na out of
the cell and K into the cell
•
Resting potential: measurable difference in voltage across the cell membrane in a
resting cell
o -70 mV
o interior of cell negative relative to the exterior
lOMoARcPSD|271398 04
BIOL 102 Notes
Liberty University- Dr. Spohn
Immune System
White blood cells
o Functions
Protection from infection
Regulation of the inflammatory reaction
o Two types
Granular
Neutrophils- 60% of circulating white blood cells
Eosinophils- 2-4%
Basophils- 0.5%
Agranular
Lymphocytes- 30%
Monocytes- 5%
Granular Leukocytes
o Neutrophils
First on the scene to fight infection by engulfing any foreign
microorganisms
o Eosinophils
Defend against parasites (worms)
Moderate severity of allergic reactions
o Basophils
Histamine in granules- role in inflammation
Agranular Leukocytes
o Lymphocytes
Play a large role in immune response
Two types
Type b lymphocytes
o Produce antibodies
Type t lymphocytes
o Attack cells directly
o Monocytes
Leave blood and transform into macrophages
Platelets
o Small cell fragments derived from megakyrocytes
o Important role in hemostasis (blood clotting)
Hemostasis
o Three stages
1. Vascular Spasm
a. Constriction of blood vessels to reduce blood flow out of
wound
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2. Platelet Plug Formation
a. Sealing of ruptured blood vessel
3. Coagulation
a. A clot
b. Complicated series of reactions
c. Fibrinogen to fibrin
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BIOL 102 Notes
Liberty University- Dr. Spohn
Blood-tuping concepts
o Antigen vs. antibody
A and B antigens
Surface markers on red blood cells
Antibodies
Immune system proteins directed against antigens
Blood disorders affecting Red Blood Cells
o Anemia
Reduction in oxygen carrying capacity due to inadequate
number of red blood cells or inadequate hemoglobin
Anemia types
Iron-deficiency anemia
o Caused by an inadequate intake or malabsorption
of dietary iron
Hemorrhagic anemia
o Caused by excessive blood loss
Pernicious anemia
o Caused by vitamin b12 deficiency
Hemolytic anemia
o Caused by the destruction of red blood cells
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Bio 102- Liberty University
Chapter 6
Skeletal Muscle Contractile Unit
Sarcomere: contractile unit
o Myosin
forms thick filaments
o Actin
forms thin filaments
2 lines- attachment points for sarcomeres
arrangement of filaments gives rise to striated appearance of skeletal muscle
Nerve Activation of Individual Muscle cells
Acetylcholine is released from motor neuron at neuromuscular junction
Electrical impulse transmitted along T tubules
Calcium released from sarcoplasmic reticulum (type of ER)
Calcium initiates the sliding filament mechanism
Thick filaments: myosin
Thin filaments: strands of actin molecules
Contraction: formation of cross bridges between thin and think filaments
Mechanism of Muscle Contraction
Calcium is released from sarcoplasmic reticulum
Calcium binds to troponin
Troponin-tropomyosin complex shifts position
Myosin binding site is exposed
Myosin heads form cross bridges with actin
Actin filaments are pulled toward center of sarcomere
Muscle Relaxation
Nerve activation ends, contraction ends
Calcium pumped back into sarcoplasmic reticulum
Calcium removed from troponin
Myosin binding site covered
No calcium=no cross bridges
Energy required for Muscle Activity
Principle source of energy
o ATP
ATP is required for contraction
ATP is required for relaxation
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ATP is replenished by a variety of means
o Creatine phosphate
o Stored glycogen
o Aerobic metabolism of glucose
o Aerobic metabolism of fatty acids
o Aerobic metabolism of high energy molecules
lOMoARcPSD|271398 04
BIOL 102 Exam 1 Notes
Liberty University- Dr. Spohn
1. Lipids are fats and oils
Fats are solid at room temperature; oils are liquid at room temperature
If there is a fair amount of phosphate they are called phospholipids
If H to C ratio is greater than 2:1, it’s a lipid not a carbohydrate
Four classes:
Triglycerides: energy storage molecules (also known as fats and oils)
o Composed of glycerol molecule + 3 fatty acid chains
o Fatty acids:
Saturated (in fats): all bonds full [blood vessels—heart
disease]
Unsaturated (in oils): double bond [doesn’t get into
blood vessels but can cause cancer]
Polyunsaturated: multiple double bonds
between C atoms
o Stored in adipose tissue
o Energy storage molecules and insulation from outside
temperature
Phospholipids: primary structure of all membranes (component of cell
membranes)
o Composed of glycerol + 2 fatty acids + phosphate group
o One end of molecule is water soluble (phosphate: hydrophilic);
other end of molecule is water insoluble (fatty acids:
hydrophobic)
Steroids: carbon-based ring structures (4 rings) [cholesterol,
hormones—testosterone and estrogen]; membrane stabilizer
*Waxes (very few organisms make this)
2. Proteins are made up of long chains (polymers) of subunits called amino acids
Amino acids:
20 different types
Amino end, carboxyl group, R group
Joined by peptide bonds, which are produced by dehydration synthesis
reactions
Can study proteins at primary, secondary, tertiary, quaternary, or
quintenary structure—function depends on its structure
Denaturation is the permanent disruption of protein structure (can be damaged
by temperature, changes in pH, or changes in salt concentrations in the cells and
heavy metal ions); leads to loss in biological function (can result in death)
Enzymes facilitate biochemical reactions; speed up chemical reactions and
aren’t altered/consumed by the reaction
Function as biological catalysts
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Without them, many biological reactions wouldn’t proceed quickly
enough to sustain life
Functional shape of an enzyme is dependent on: temperature, pH, ion
concentration, presence of inhibitors
3. Nucleic Acids store genetic information and provide information used in making proteins
Long chains containing subunits known as nucleotides (building blocks of nucleic
acids: five carbon sugar + nitrogen base + phosphate group)
Two types:
DNA (deoxyribonucleic acid):
o Double-stranded
o Nucleotide: deoxyribose, nitrogenous bases (adenine-thymine,
guanine-cytosine)
RNA (ribonucleic acid):
o Single-stranded
o Nucleotide: ribose, nitrogenous bases (adenine-uracil, guanine-
cytosine)
o Three different kinds:
mRNA: messenger RNA; copy instructions on how to
make proteins
rRNA: ribosome RNA; read and transcribe instructions
from mRNA (in smooth and rough ER)
tRNA: transfer RNA; bring amino acids to ribosome
DNA (instructions for making RNA) RNA (instructions for making proteins)
proteins (direct most of life’s processes)
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lOMoARcPSD|271398 04
Bio 102- Liberty University
Chapter 6
Exercise training
Strength training
o Resistance training
o Short, intense
o Builds fast twitch muscle myofibrils
Aerobic training
o Builds endurance
o Increase blood supply to muscle cells
o Reach target heart rate for at least 20 minutes 3 times a week
Activation of Cardiac and Smooth Muscles
Involuntary
Able to contract entirely on their own and in absence of nerve stimulation
Respond to stimulation from autonomic nervous system, which can modify the degree
of contraction
Speed and Sustainability of Contraction
Skeletal muscle: fastest
Cardiac muscle: moderate
Smooth muscle
o Very slow
o Partially contracted all the time
Cardiac and Smooth Muscles
Cardiac muscle
o Sarcomere arrangement of thick and thin filaments
o Striated muscle
Smooth muscle
o Filaments arranged in criss-crossed bundles, not sarcomeres
o No striations
Diseases and Disorders of the muscular system
Muscular distrohphy
Tetanus
Muscle cramps
Pulled muscles
Fasciitis
Chapter 7: Blood
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Three Primary functions of blood
Transportation
o Nutrients, waste, hormones
Regulation
o Temperature, water volume, pH
Defense
o Against infections and bleeding
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BIOL 102 Notes
Liberty University- Dr. Spohn
Hormones participate in negative feedback loops
Many hormones participate in internal homeostatic control mechanisms
Negative feedback loop involving hormones include the following
o Endocrine gland serves as the control center
o Hormone is the pathway between the control center and the effectors
o Target tissues or organs are the effectors
Hypothalamus and the Pituitary Gland
Hypothalamus
o Homeostasis control center of the brain
o Links nervous system and endocrine system
o Produces two hormones of its own
o Monitors and controls secretions of the pituitary gland
Pituitary gland
o “master” gland
o secretes eight different hormones that regulate other endocrine organs
o two lobes: posterior and anterior
Has a protective structure around it in the skull
Posterior pituitary
o Connection to hypothalamus
o Hormones made in hypothalamus, stored in posterior pituitary
p306 table 13.1: know those hormones
Exam 4 Material ^^^
Chapter 14
Digestive system brings nutrients into the body
The digestive system includes
o Gastrointestinal (GI) tract (hollow tube)
Lumen: space within this tube
Includes mouth, pharynx esophagus, stomach, small intestine, large
intestine, rectum, anus
o Accessory Organs
Salivary glands, liver, gallbladder, pancreas
o See figure 14.1
Walls of the GI tract are composed of 4 layers
Common layers throughout the system
o Mucosa
Innermost layer, mucous membrane in contact with the lumen
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o Submucosa:
Layer of connective tissue containing blood vessels, lymph vessels, nerves
o Muscularis:
Two or three layers (three in stomach, two everywhere else) of smooth
muscle, responsible for movement, motility
o Serosa
Outermost layer
Sphincters: thick muscular rings that separate some of the organs (inside the muscularis
layer)
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Bio 102 Liberty University
Chapter 16 Notes
Reproductive System
Male Reproductive System delivers sperm
Testes produce sperm
o Scrotum- sac of skin and smooth muscle that hold the testes
Maintains testes at a slightly lower temperature
o Seminiferous tubules within testes: produce sperm
Epididymis and ductus deferens: sperm become motile and are stored here
Ductus deferens: transports sperm to where it becomes the ejaculatory duct
Route of sperm through male reproductive structures
o Seminiferous tubules
o Epididymis
o Ductus deferens
o Ejaculatory duct
o Penis
It takes 64 days for a cell to become sperm
**Sperm can only fertilize eggs after it has come into contact with female tissue for a few
hours**
Accessory Glands help sperm survive
Seminal vesicles- 60% of fluid in semen
o Secrete fructose (provide source of energy for sperm) and most of seminal fluid
Prostate gland
o Secretes watery alkaline fluid to raise vaginal pH
Bulbourethral gland
o Secretes lubricating mucus
o Cleanses urethra
o *prostaglandin- causes wavelike contractions of the uterus to move sperm to the
egg
**a normal ejaculation releases hundreds of millions of sperm, only 100 or 200 might get near
an egg**
Sperm production requires cell division
Meiosis- two special cell divisions in which you half the chromosome number and
shuffle the genetic information so that every sperm/egg is different
Sertoli cells provide support and nourishment
Testosterone affects male reproductive capacity
Testosterone
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o Steroid hormone produced by interstitial cells in testes (between seminiferous
tubules)
o Function: controls growth and function of male reproductive tissues, stimulates
aggression and sexual behaviors, and secondary sexual characteristics
o Determines rate of sperm formation
Hormones that regulate testosterone and sperm production
o Gonadortropin-releasing hormone (GnRH) from hypothalamus
o LH (from anterior pituitary) stimulates production of testosterone
o FSH (from anterior pituitary) may enhance sperm formation with Sertoli cells
o Inhibin: produced by Sertoli cells, inhibits secretion of FSH
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lOMoARcPSD|271398 04
BIOL 102 Notes
Liberty University- Dr. Spohn
Five Basic Processes accomplish digestive system function
1. Mechanical Processing and Movement
a. Chewing and mixing
2. Secretion
a. Fluid
b. Digestive enzymes and hormones
c. Bile, acid, alkali, mucus
3. Digestion
a. Breaking down food to smallest absorbable units
b. Chemical and mechanical breakdown
4. Absorption
a. Through mucosa
b. Into blood or lymph vessels
5. Elimination
a. Undigested material eliminated
Two types of motility aid digestive processes
Motility enable by smooth muscle in the muscularis layer
Peristalsis: propels food forward
Segmentation: mixes food
The mouth processes food for swallowing
Teeth: bite and chew food
o Types: incisors, canines, premolars, molars
Children: 20 teeth
Adults: permanent teeth
o Structure: crown, root
Tongue: positions and tastes food
o Skeletal muscle
o Moves food in mouth
o Taste
o Important for speech
Saliva
o Salivary glands
Parotid
submandibular
sublingual
o composition
mucin, salivary amylase, bicarbonate, lysozyme
swallowing reflex occurs when the bolus moves to the pharynx
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o involuntary reflex
o moves food down esophagus through peristalsis and through the cardiac
sphincter to the stomach
Stomach
storage facility (do not absorb nutrients through the stomach)
keep food from a meal for 2-6 hours in the stomach
three layers of muscles in stomach
mix food with gastric juice
o contains:
HCl- hydrochloric acid
Intrinsic factor (helps absorb vitamin b12)
Both of these substances are produced by chief cells in the gastric
pits
Mucus
Pepsinogen- when mixed with HCl, it is converted to pepsin which helps
break down proteins
o Resulting product is called chyme
Small Intestine
10ft 10in long
o all digestion occurs in first 10 inches
o all absorption occurs in 10 feet
3 regions
o duodenum- where digestion takes places (first 10 inches)
o Ileum- where absorption occurs, 10 ft portion
o Jejenum- where absorption occurs, 10 ft portion
Duodenum
o Input from Pancreas
Digestive enzymes: emptied into the front of the small intestine along
with sodium bicarbonate
Proteases
Carbohydrases
Lipases
o Input from Liver
Bile: produced in the liver, concentrated and stored in the gallbladder
An emulsifier
Liver acts as a storage facility, synthesizes bile and urea, detoxifies
Large Intestine
5 feet long
Ascending, transverse, descending, and sigmoid colon, rectum and anus elimination
(fiber and bacteria)
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Bio 102 Liberty University
Dr. Spohn
Chapter 15 notes
Tubular secretion removes other substances from the blood
Involves the movement if materials from the peritubular capillaries or vasa recta to the
tubule
Purpose
o Regulation of chemical levels in body
o Excretion of harmful chemicals
Producing Dilute Urine: Excreting excess water
Kidneys respond to excess water by excreting it
Mechanism
o Distal tubule is impermeable to water
o NaCl is reabsorbed
Producing Concentrated urine: conserving water
Too little water can lead to lower blood volume, declining blood pressure, risk of
dehydration of body cells
Kidneys respond by conserving water and producing more concentrated urine
Mechanism
o Mediated by ADH from the posterior pituitary gland
o ADH increases permeability of the collecting ducts to water and increases
conservation of water
Urination depends on a reflex
Micturition reflex
o Responds to stretch receptors in bladder wall
o Internal urethral sphincter
Smooth muscle
o External urethral sphincter
o Skeletal muscle, under voluntary control
Brain can override the micturition reflex and control the timing of urination
Voluntary control becomes increasingly difficult as the bladder gets full
Kidneys Maintain homeostasis in many ways
Maintain water balance
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o Adjust blood volume and blood pressure
Aldosterone, renin, ANH helps maintain salt balance in order to control blood volume
Maintain acid-base balance and blood pH
Regulate red blood cell production via erythropoietin
Activate an inactive form of vitamin D
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Fat and Glycogen: Sources of Energy
- Fat (lipid)
o Triglycerides
o Long-term energy storage in animals (twice as much energy as any other molecule)
- Glycogen
o Carbohydrate storage
o Short-term energy storage in animals
Cell Structures for Support and Movement
- Cytoskeleton
o Microtubules
o Microfilaments proteins help cytoskeleton keep its shape
o Intermediate filaments
- Cilia (short, many); found on cells lining airways (nasal packages)
- Flagella (long, single); enable spermatozoa to swim
- Centrioles
Cells Use and Transform Matter and Energy
- Anabolism + Catabolism = Metabolism
o All chemical reactions that occur in a cell organism are metabolism
- Anabolism
o Requires enzymes
o Used in making/assembling large molecules (dehydration synthesis)
o Requires energy (ATP)
o Used in building and assembling cell components
o Used to access energy storage
- Catabolism
o Requires enzymes
o Breakdown of molecules (provides energy for anabolism)
o Releases energy
o Used in breaking down nutrients and recycling cell components
o Used to access energy storage
o (Hydrolysis)
Glucose Provides Cell with Energy
- Glucose provides energy for the cell (primary)
- Energy in glucose is used to generate ATP
- In absence of glucose, other carbohydrates, fats, and proteins can be catabolized to generate
ATP
- Three stages of cellular respiration (complete breakdown of a food molecule)
o Glycolysis
o Citric Acid Cycle
o Electron Transport System
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Glycolysis
- *occurs in cytoplasm (outside cell)
- Series of 10 reactions that split glucose into two molecules of pyruvic acid
- *Two ATP molecules are produced (net)—costs 2 ATP molecules to get the glycogen to react,
but you get 4 ATP molecules in the end = net gain of two
- ~High-energy electrons and hydrogen ions are removed and picked up by coenzyme NAD+
forming NADH
- Starts with 6-carbon compound and ends in two 3-carbon compounds
lOMoARcPSD|271398 04
BIOL 102 Exam 1 Notes
Liberty University- Dr. Spohn
Water
- Life depends on water
o Water molecules are polar (tear ionic compounds apart)
o Liquid at body temperature; helps regulate body temperature (gets rid of heat when
water evaporates through sweat)
o Can absorb/hold heat energy
o Biological solvent
Solvent is a liquid in which other substances dissolve
Solute is any dissolved substance
Polar molecules that are attracted to water and interact easily with it are
hydrophilic
Nonpolar neutral molecules that do not interact with or dissolve in water are
hydrophobic
Importance of Hydrogen Atoms
- Acids donate H ions (p+); increase H ion concentration in solutions
- Bases accept H ions (p+); lower H ion concentration in solutions
- pH Scale is a measure of H ion concentration in a solution ranging from 0-14 *when pH increases
by 1, concentration increases 10-fold
o Acids: pH < 7
o Bases: pH > 7
o Neutral: pH = 7
Buffers are any molecules that tend to minimize the changes in pH that may occur when an acid
or base is added to a solution
- Weak acid and the salt of that acid
- Carbonic acid and bicarbonate act as one of the body’s most important buffer pairs (HCO3- + H+
H2CO3 + NaHCO3)
Organic Molecules of Living Organisms
- Carbon is the building block of all living things
o Comprises 18% of the body by weight
o Can form single, double, or triple bonds
o Can build micro- or macromolecules
- Macromolecules are synthesized and broken down within a cell
o Dehydration synthesis removes equivalent of a water molecule to link molecular units;
requires energy; builds macromolecules from smaller subunits
o Hydrolysis adds the equivalent of a water molecule to break apart macromolecules;
releases energy
- Four Kinds of Organic Molecules:
1. Carbohydrates are used for energy and structural support
General formula is Cn(H2O)n (CH2O)n
Hydrogen to carbon ration must be 2:1
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Monosaccharides are simple sugars (deoxyribose, ribose, glucose, fructose, and
galactose)
Fiber helps digestive system and protects digestive tract from colon cancer
(even though we can’t digest them/break them down, we need them to keep
healthy)
Oligosaccharides are more than one monosaccharide linked together via
dehydration synthesis
Disaccharides are two monosaccharides linked together
o Sucrose: glucose + fructose
o Maltose: glucose + glucose
o Lactose: glucose + galactose
Polysaccharides are thousands of monosaccharides joined in chains and
branches
o Starch: made in plants; stores energy
o Glycogen: made in animals; stores energy
o Cellulose: indigestible polysaccharide made in plants for
structural support
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Connective Tissues
- Mostly matrix—separated from each other; cells embedded in nonliving extracellular matrix
(gel-like ground substance; gives CT strength and characteristics)
- General functions:
o Support softer organs of body
o Connect parts of body
o Store fat
o Produce blood cells (made in red bone marrow)
- Two general types:
o Fibrous
Function: provides strength and elasticity
Contains fibers and cells embedded in matrix
Cells: fibroblasts, macrophages, lymphocytes, and neutrophils
Fibers: collagen, elastic, and reticular
Four General Types:
Loose: surrounds many organs, lines cavities, around blood vessels
Dense: forms tendons, ligaments, deeper layers of skin
Elastic: surrounds stomach and bladder; maintains shape
Reticular: makes up internal framework of soft organs (liver) and
lymphatic system
o Special
Cartilage: produced by chondroblasts found in lacunae (depressions in tissue);
no blood vessels; high collagen content
Bone: inorganic matrix with calcium salts for hardness
Blood: fluid matrix of plasma, RBCs and WBCs, and platelets
Adipose Tissue: fat cells; function in insulation, protection, and energy storage
Muscle Tissues
- Skeletal: moves body parts; voluntary, multinucleated (cylindrical—striated)
- Cardiac: functions in the heart; involuntary (auto-rhythmic); single nucleus (branch:
anastomosis—striated)
- Smooth: surrounds hollow structures; involuntary; single nucleus; can’t fatigue (make ATP faster
than use it) (spindle-shaped)
Nervous Tissues
- Neuron: specialized nervous system cell
o Function: generate and transmit electrical impulse
o Structural components: cell body, dendrites, axon
- Glial cells (neuroglia cells): support neurons
Organs and Organ Systems Perform Complex Functions
- Organs: contain two or more tissue types joined together; perform specific functions
- Organ Systems: groups of organs that perform a common function
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o Examples:
Digestive system: mouth, throat, stomach, intestines, liver
Lymphatic system: lymph nodes, tonsils, and spleen
Tissue Membranes
- Serous membranes: reduce friction between organs
- Mucous membranes: lubricate surface, capture debris
- Synovial membranes: line spaces in movable joints
- Cutaneous membranes: skin
Multicellular Organisms Must Maintain Homeostasis
- Homeostasis: maintenance of relative constancy of the conditions of the internal environment
(OR: tendency of every organism to maintain a constant internal environment)
- Negative Feedback Control System: deviations from normal are detected and counteracted
o Components:
Controlled variable
Sensor
Control center
Effector
o Helps maintain core body temperature
Controlled variable: body temp
Sensors: temp sensors in the skin and internal organs
Control center: hypothalamus
Effectors: blood vessels, sweat glands, and skeletal muscles
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BIOL 102 Notes
Liberty University- Dr. Spohn
Chapter 2: The Chemistry of Living Things
General Definitions
- Chemistry is the study of matter and energy that relates to how things combine, break apart,
and rearrange
- Matter is anything that has mass and occupies space; composed of elements *equivalent to
weight for this course
- Elements are fundamental forms of matter that cannot be broken down into a simpler form
o Periodic table of the elements organizes them
- Atoms are the smallest functional unit of an element
o Nucleus (central core)
Protons (+) have mass
Neutrons (o) have mass
o Shells surround nucleus
Electrons (-) have no discernable mass
All atoms “want” their outer shell to have max number of e- or 8e- (1st: 2; 2nd: 8;
3rd: 8)
- Atomic symbol is one or two letters representing an element
- Atomic number is the number of p+ (also the number of e- before a reaction happens)
- Mass number roughly equals p+ + no
- Isotopes have a different number of no than usual
o Same atomic number (p+) but different atomic mass (varying number of no)
o Radioisotopes are unstable isotopes
Give off energy (in form of radiation) and particles to try to become stable (can
change into completely different element)
Scientific and medical uses:
Carbon-14: used for dating fossils (because when you die, you stop
exchanging C with the atmosphere)
Diagnostic imaging
Cancer treatment
Power supply for implants (ie pacemakers)
Energy Fuels Life’s Activities
- Energy is the capacity to do work
o Potential energy is stored energy (can be turned into kinetic)
o Kinetic energy is energy in motion, doing work
- E- have potential energy (each shell corresponds to a specific level of potential energy: further
shells have more energy thus bigger atoms are more powerful)
- Atoms are most stable when outermost shell is full or has 8e-
- Atoms will interact with other atoms to fill their outermost shells (or reach 8)
Chemical Bonds are attractive forces that hold atoms together (molecules)
- Molecule is two or more atoms chemically bonded together
lOMoARcPSD|271398 04
- Compound is two or more different atoms bound together
- Three kinds of bonds:
o Covalent: atoms share e- (strongest bonds) [ex. H2, O2]
Two kinds:
Nonpolar: e- shared equally [H2, O2, CH4]
Polar: e- not shared equally [H2O: the O has a stronger pull on the
shared e- than the H does]
o Ionic: one atom gains/loses an e- (opposites attract); attractive force between oppositely
charged ions [NaCl]
Ion is an electrically charged atom/molecule
Positively charged ion forms if e- is lost
Negatively charged ion from is e- is gained
o Hydrogen: weak attraction between oppositely charged regions of polar molecules [ex.
Weak forces between water molecules]
Polar molecules:
Contain polar covalent bonds in which there is unequal sharing of e-
Electrically neutral overall, but even charge distribution
lOMoARcPSD|271398 04
BIOL 102 Exam 1 Notes
Liberty University- Dr. Spohn
ATP (adenosine triphosphate) Carries Energy (modified nucleotide)
- Universal energy source
- Bonds between phosphate group contain potential energy; breaking the bonds releases energy
o ATP ADP + P + energy
Chapter 3a: Structure and Function of Cells
Cell Doctrine (Schwann and Schleider 1838, 1839): all living things are composed of cells
- A single cell is the smallest unit that exhibits all of the characteristics of life
- All cells only come from preexisting cells
Two Basic Cell Types (classified by internal organization)
Prokaryotic
Eukaryotic
Plasma membrane
Plasma membrane
No nucleus (DNA floats in cytoplasm)
Nucleus: information center
Cytoplasm: fluid within membrane
Cytoplasm: fluid within membrane
No “true” organelles—have ribosomes
(still have functions but not within
“packages”)
Organelles: structures with specialized
functions
*Found in bacteria and blue-green algae
All human cells
Cell Structure Reflects Cell Function
- Eukaryotic cells are remarkably similar to each other but have structural differences
o Ex. Muscle Cells: contain numerous organelles providing energy needed for muscle
contraction vs. Nerve Cells: long and thin to carry impulses over distance
- Small size is efficient
o Cannot be seen without magnification
o Microscopes enable visualization and study of cells
Light microscope magnifies up to 1000x
Transmission electron microscope magnifies up to 100,000x
Scanning electron microscope magnifies up to 100,000x and provides 3D view of
cell surface
o Small cells have a higher surface to volume ratio
High surface to volume ration promotes efficiency in 1) acquisition of nutrients
and 2) disposal of wastes
Plasma Membrane Surrounds the Cell
- Separates cell from its environment
- Selectively permeable
- Enables transfer of information between environment and cell
- Plasma membrane is a lipid bilayer
lOMoARcPSD|271398 04
o Phospholipids: polar head and nonpolar tail
o Cholesterol: makes membrane a bit more rigid
o Carbohydrates: recognition patterns for cells and organisms
- Non-rigid
- Fluid mosaic
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lOMoARcPSD|271398 04
Chapter 3b: Structure and Function of Cells
Nucleus
- Functions: contains genetic information for and controls the cell
- Structural Features:
o Double-layer nuclear membrane
o Nuclear pores
o Chromosomes/chromatin (DNA, start and stop codes for each protein)
o Nucleolus (“little nucleus”—specialized bit of genetic info that codes for a ribosome
which will synthesize proteins
Ribosomes
- Site of protein synthesis
- Location:
o Free: floating/cytoplasm
o Bound: attached to outer surface of endoplasmic reticulum
Endoplasmic Reticulum (ER)
- Actually continues toward outside of the cell so it connects to the ER of another cell
- Two types:
o Rough ER: has ribosomes on surface
Manufactures and modifies proteins
o Smooth ER: no ribosomes on surface
Synthesizes lipids and packages proteins
Golgi Apparatus
- Refines synthesized products
- Packaging and shipping center
- Products are packaged into vesicles and shipped to other locations within the cell or to cell
membrane for export (exocytosis)
- *Goblet cells: major feature is the giant Golgi apparatus that protects stomach cells from
stomach acid
- *Plant scientists call them *dictyosomes
Vesicles
- Storage and shipping vesicles
- Secretory vesicles
- Endocytic vesicles:
o Peroxisomes: contain enzymes that detoxify
o Lysosomes: contain digestive enzymes
Literally means “death body”—can digest everything in a cell; therefore, they
are packaged so they can’t get out until needed to destroy bacteria
Also how we develop fingers and toes (we have paddles. Apoplosis: paddles
separate into fingers/toes)
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Mitochondria
- “power plant” of the cell
- Surrounded by double membrane
- Utilizes O2 and produces CO2
- Generates ATP
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BIOL 102 Exam 1 Notes
Liberty University- Dr. Spohn
Molecules Cross Plasma Membrane in Several Ways
- Passive Transport: cell does not need to expend energy; powered by concentration gradient;
occurs as:
o Diffusion: movement of atoms from area of higher to lower concentration
Through lipid layer
Through protein transport
Facilitated transport: transport/carrier proteins in membrane assist in moving
molecules across the membrane, down the concentration gradient, without
expending energy
o Osmosis: specifically relates to diffusion of water
- Active Transport: cell must expend energy; usually moves molecules against concentration
gradient from area of lower concentration to an area of higher concentration
o Requires membrane protein (transporter)
o Requires ATP or other energy source
- Bulk Transport: involves membranous vesicles to move larger substances/molecules
o Endocytosis: adding to cell by bringing in substances
o Exocytosis: eliminating from cell by expelling substances
Information Transfer across Cell Membrane
- Receptor proteins span membrane—required for transmission of information to and from cell
- Receptor sites (on receptor proteins)—interact specifically with signal molecules
- A change is triggered within the cell as a result of the binding of signal molecules to the receptor
site
- Different cell types have different receptor proteins
The Sodium-Potassium Pump (helps maintain cell volume)
- Expels unwanted ions, keeps needed ones, and maintains cell volume
- ATP is used to expel 3 sodium ions for every 2 potassium ions brought into the cell
- Increase in cell volume = increase in water in cytoplasm by decreasing pumping and allowing
more sodium inside cell
- Decrease in cell volume = less water in cytoplasm by increasing pumping and expelling more
sodium ions
Isotonic Extracellular Fluid Maintains Cell Volume
- Tonicity: relative concentration of solutes in two fluids
- Isotonic: no change in cell volume
o Extracellular and intracellular ionic concentrations are equal (iso)
o Cells maintain a normal volume in isotonic extracellular fluids
o Regulatory mechanisms maintain extracellular fluid that is isotonic with intracellular
fluid
- Variations in tonicity
o Hypertonic: extracellular ionic concentration higher than intracellular
Water will diffuse out of the cell causing the cell to shrink and die (*crenate)
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o Hypotonic: extracellular ionic concentration lower than intracellular
Water will diffuse into the cell causing cell to swell and burst (doesn’t happen to
plant cells)
Plasmolysis: contraction of the protoplast of a plant cell as a result of
loss of water from the cell.
Hemolysis: blowing up red blood cells—their exposure to hypotonic
solution
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Citric Acid Cycle (Krebs Cycle)
- Occurs in mitochondria
- Extracts high-energy electrons to form NADH and FADH2
- *Produces 2 ATP molecules and CO2 from carbon compound fragments
Electron Transport Cycle (Oxidative Phosphorylation)
- *Located in inner mitochondrial membrane (requires oxygen)
- Takes electrons from NADH and FADH2
- Movement of e- from one carrier to the next releases energy that is harvested to generate ATP
- Final e- acceptor is O2 which forms water upon receiving e- and H atoms
- *Produces 32 ATP molecules
Additional Energy Sources
- Glycogen
- Fats (triglycerides have twice the energy of carbohydrates)
- Proteins (same energy as carbohydrates)
Chapter 4: From Cells to Tissues
Tissues
- Groups of cells with common function
- Four primary tissue classes:
o Epithelia (line/cover)
o Connective (connect)
o Muscular (contract)
o Nervous (transmit impulses)
Epithelial Tissues
- Line body cavities and cover surfaces (primary cells with a little “glue”—tightly joined)
- Glandular epithelia
o Epithelial cells adapted to make up glands
o Exocrine glands: secrete into ducts to exterior of body (sebaceous and oil)
o Endocrine glands: secrete into the blood to carry chemical messages throughout the
body (hormones; ductless)
- Classification
o Shape:
Squamous: flattened cells; line vessels; part of lungs; body surfaces
Cuboidal: cube-shaped; form lining of tubules; glandular tissue tracts
Columnar: column-shaped; line respiratory, digestive, and reproductive tracts
o Layers:
Simple: single-layered; adapted for diffusion across cell barriers; line glands and
respiratory, digestive, and reproductive systems
Stratified: multi-layered; provide protection, as in skin surface
- The basement membrane provides structural support to overlying cells
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o Attaches epithelial layer to underlying tissues (typically connective)
o Junctions: hold epithelial cells together
Tight Junctions: nothing passes between cells (skin)
Adhesion Junctions: (spot desmosomes) some movement between cells
Gap Junctions: protein channels; direct transfer of water and ions between
adjacent cells
