Assignment 1: Biology Article
voncolio
ch_2_-_molecules_of_life.pptxdrain cleaner
bleach
oven cleaner
hair remover
more basic
household ammonia
milk of magnesia hand soap
toothpaste
Tums detergents baking soda
seawater
egg white blood, tears
pure water
milk butter corn
urine, tea, typical rain black coffee
bread
beer
bananas
tomatoes, wine
orange juice
more acidic
vinegar
cola lemon juice
acid rain
gastric fluid
battery acid
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10
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6
5
4
3
2
1
0
Figure 2.12 A pH scale. Here, red dots signify
hydrogen ions (H+) and blue dots signify hydroxyl
ions (OH–). Also shown are the approximate pH
values for some common solutions.
This pH scale ranges from 0 (most acidic) to 14
(most basic). A change of one unit on the scale
corresponds to a tenfold change in the amount
of H+ ions.
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Inorganic Molecules
Water
Oxygen
Carbon Dioxide
Salts
Organic Molecules
Carbohydrates
Lipids
Proteins
Nucleic Acids
C
C
C
C
C
C
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
C
H
C
H
C
H
H
C
H
H
H
H
H
H
C
C
H
H
C
H
H
C
H
H
Organic Molecules
Condensation
Figure 2.15 Animated!
Metabolism: two common reactions by
which cells build and break down organic
molecules.
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Hydrolysis
Figure 2.15 Animated!
Metabolism: two common reactions by
which cells build and break down organic
molecules.
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Carbohydrates
Monomer = simple sugar (monosaccharide)
Polymers = disaccharides or polysaccharides
Cellulose
Starch
Glycogen
Figure 2.16 Animated! Three of the
most common complex carbohydrates and their
locations in a few organisms. Each polysaccharide
consists only of glucose units, but different
bonding patterns that link the subunits result in
substances with very different properties.
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Lipids
Insoluble in water = Hydrophobic
hydrophobic “tail”
A) stearic acid (saturated)
B) linoleic acid (omega-6)
C) linolenic acid (omega-3)
D) oleic acid (cis)
E) elaidic acid (trans)
“head” (hydrophilic carboxyl group)
Figure 2.17 Animated! Fatty acids. Double bonds in the tails are colored red.
A The tail of stearic acid is fully saturated with hydrogen atoms. B Linoleic acid, with two double
bonds, is unsaturated. The first double bond occurs at the sixth carbon from the end of the tail, so
linoleic acid is called an omega-6 fatty acid. Omega-6 and C omega-3 fatty acids are “essential fatty
acids,” which means your body does not make them and they must come from food.
D The hydrogen atoms (in blue) around the double bond in oleic acid are on the same side of the tail.
Most other naturally occurring unsaturated fatty acids have these cis bonds. E Hydrogenation creates
abundant trans bonds, with hydrogen atoms on opposite sides of the tail (in blue).
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hydrophilic head
two hydrophobic tails
A phospholipid molecule
Figure 2.18 Phospholipids as components of cell membranes. A double layer of
phospholipids—the lipid bilayer—is the structural foundation of all cell membranes.
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Figure 2.18 Phospholipids as components of cell membranes. A double layer of
phospholipids—the lipid bilayer—is the structural foundation of all cell membranes.
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an estrogen
testosterone
female
wood duck
male
wood duck
Figure 2.19 Estrogen and testosterone, steroid
hormones that cause different traits to arise in males
and females of many species such as wood ducks.
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Proteins
Monomer = amino acids
Polymers = proteins
Figure 2.20 Animated! How protein structure arises. Chapter 7 returns to protein synthesis.
1 A peptide bond forms between two
amino acids (here, methionine and valine).
2 More amino acids become linked into a
polypeptide chain. The sequence of amino
acids in the chain is the protein’s primary
structure. Each type of protein has a unique
primary structure.
3 Secondary structure
arises as the polypeptide
twists into a coil or sheet
held in place by hydrogen
bonds. Most proteins
have coils and sheets.
4 Tertiary structure occurs
when the coils and sheets
fold up into a domain. In
this example, the coils of a
globin chain form a pocket.
5 Some proteins have two or more
polypeptide chains. Hemoglobin,
shown here, consists of four globin
chains ( green and blue). Each globin
pocket now holds a heme group (red ).
6 Fibrous proteins aggregate by the
many thousands into much larger
structures. The filaments that make
up hair are examples; they consist of
tightly bundled keratin proteins.
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Figure 2.20 Animated! How protein structure arises. Chapter 7 returns to protein synthesis.
1 A peptide bond forms between two
amino acids (here, methionine and valine).
2 More amino acids become linked into a
polypeptide chain. The sequence of amino
acids in the chain is the protein’s primary
structure. Each type of protein has a unique
primary structure.
3 Secondary structure
arises as the polypeptide
twists into a coil or sheet
held in place by hydrogen
bonds. Most proteins
have coils and sheets.
4 Tertiary structure occurs
when the coils and sheets
fold up into a domain. In
this example, the coils of a
globin chain form a pocket.
5 Some proteins have two or more
polypeptide chains. Hemoglobin,
shown here, consists of four globin
chains ( green and blue). Each globin
pocket now holds a heme group (red ).
6 Fibrous proteins aggregate by the
many thousands into much larger
structures. The filaments that make
up hair are examples; they consist of
tightly bundled keratin proteins.
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Figure 2.20 Animated! How protein structure arises. Chapter 7 returns to protein synthesis.
1 A peptide bond forms between two
amino acids (here, methionine and valine).
2 More amino acids become linked into a
polypeptide chain. The sequence of amino
acids in the chain is the protein’s primary
structure. Each type of protein has a unique
primary structure.
3 Secondary structure
arises as the polypeptide
twists into a coil or sheet
held in place by hydrogen
bonds. Most proteins
have coils and sheets.
4 Tertiary structure occurs
when the coils and sheets
fold up into a domain. In
this example, the coils of a
globin chain form a pocket.
5 Some proteins have two or more
polypeptide chains. Hemoglobin,
shown here, consists of four globin
chains ( green and blue). Each globin
pocket now holds a heme group (red ).
6 Fibrous proteins aggregate by the
many thousands into much larger
structures. The filaments that make
up hair are examples; they consist of
tightly bundled keratin proteins.
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Nucleic Acids
Monomer = nucleotide
Polymers = DNA or RNA
ribose
sugar
base (adenine)
phosphate
groups
Figure 2.22 Nucleic acids.
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RNA
Figure 2.22 Nucleic acids.
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DNA
RNA
Figure 2.22 Nucleic acids.
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Figure 2.22 Nucleic acids.
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