Lab Assignment
Jasros09
CH2lect-handout.RTFAPI - Ch. 2: Chemical Basis of Life Week 2
1
TYPE OF BOND
DEFINITION
DESCRIPTION
EXAMPLE
IONIC
when atoms lose or gain electrons becoming ions, and then oppositely charged ions are attracted to one another
bond is broken by water
salts, e.g. NaCl
COVALENT
when 1 or more pair(s) of electrons are shared by atoms
strong bond
the bonds holding H20 together (intra-), CO2
HYDROGEN
when a (slightly positive) hydrogen atom that is already covalently bonded to something else is attracted to a slightly negative atom.
Very weak bond; in molecules whose purpose is to easily break and then come back together
reactions between water molecules (inter-; i.e. ice to water to gas);
DNA chains
SYNTHESIS
REACTIONS
DEGRADATION REACTIONS
GENERAL DESCRIPTION
Synthesis = building of large molecule (polymer) from smaller blocks (monomer).
Degradation involves the breakdown of polymer into individual monomers.
DESCRIPTIVE TERMS
building
constructive
anabolic
breakdown
digestive/decomposition
catabolic
Bond forming or breaking?
Bonds are formed.
Bonds are broken.
IS ENERGY REQUIRED
OR RELEASED?
NAME THAT TERM.
Energy is required to form the bond.
Endergonic
Energy is released when the bond is broken.
Exergonic
HOW IS WATER
INVOLVED?
NAME THAT TERM.
Water is released when he bond is formed.
Dehydration
Water is added to break the bond.
Hydrolysis
EXAMPLE
Building a protein from individual amino acids;
Building a triglyceride from glycerol and 3 fatty acids, etc
Breaking a protein into individual amino acids;
Breaking starch down into monosaccharides, etc.
Organic
Molecules
Sugars -Carbohydrates
Lipids (Fats) -
Hydrocarbons
Proteins
Nucleic Acids
Made up of Elements with these Atoms. . .
C, H, O
C, H
C, H, O, N, S
C, H, O, N, P
Chemical Structure is Characterized by . . .
chain of hydrocarbons to which hydroxyl groups (-OH) and an aldehyde group (H-C=O) are attached;
some sugars exist in ring form and not as a chain
chain of hydrocarbons ending in a carboxyl group (-COOH);
if saturated, then no double bonds (stearic acid = stearate);
if unsaturated, then with double bonds (oleic acid= oleate; linoleic acid = linoleate)
2 amino acids join to form a peptide bond (NH-CO);
each ends in a carboxyl group (-COOH) and an amino group (-NH2);
in all known 26 amino acids only 2 contain S:
Met, Cys
DNA and RNA consist of nucleotides (sugar + base + phosphate);
the sugar is in ring form of COH; the bases contain the N;
the phosphate groups (PO4) are attached to the sugar
SUBATOMIC PARTICLE SUMMARY TABLE
SUBATOMIC
PARTICLE
CHARGE
LOCATION
PROTONS
positive
nucleus
NEUTRONS
zero (neutral)
nucleus
ELECTRONS
negative
valence shells = orbitals around nucleus
Organic
Molecules
Sugars -Carbohydrates
Lipids (Fats) -
Hydrocarbons
Proteins
Nucleic Acids
Atoms?
C, H, O
C, H
C, H, O, N, S
C, H, O, N, P
Building Blocks (monomers)
monosaccharides or hexoses
acetic acid (2-carbon-unit);
triglycerides: glycerol and 3 fatty acids;
steroids
amino acids
nucleotides: pentose sugar, phosphate, nitrogen base
Specific types / function of
monomers
glucose, fructose, galactose /
energy
acetic acid-Co- enxyme A / fatty acid and steroid synthesis
TG / energy storage
phospholipids / cell membrane components
20 different amino acids
DNA and RNA nucleotides
store energy in phosphates (PO4) that are attached to the sugar moiety
Specific types / functions of polymers
disaccharides:
sucrose, lactose, maltose; energy
polysaccharides:
starch (plant);
glycogen (animal); energy storage.
fatty acids / energy storage, membrane components
steroid / cell membrane components (i.e. cholesterol); hormones
proteins (>100 amino acids) /
enzymes,
antibodies,
cell structure components, transport, hormones,
storage
DNA (double stranded) /
transcription into mRNA
RNA (single stranded) /
translation into proteins
Other
Saturated = fatty acids with single bonds between Cs; Unsaturated = double bonds between Cs
DNA is the genetic material ; it contains information in the specific order of nucleotides; controls cellular activity by instructing cells what proteins (i.e. enzymes) to make
