Transcript Survey of Vertebrate Animals

Honors
Biology
Ch. 6
Chemistry in
Biology
I. Atoms, Elements,
and Bonding
- Living and nonliving things are made
of atoms.
A.Element
- pure substance of only 1
type of atom
- 98 natural elements
- CHNOPS
The Size of Cells and Their
Components
B. Atoms
- smallest unit of matter
Atomic Models
Electron
Shell
Nucleus
Hydrogen (H)
Helium (He)
B. Atoms
- smallest unit of matter
1. Nucleus contains:
- Protons
- Neutrons
Charge
positive
neutral
Mass
1
1
2. Electrons
negative
0
C. Isotopes
- forms of an element with varying
number of neutrons
- 12C vs. 14C
D. Compounds and Bonding
- 2 or more elements chemically bonded
1.Covalent Bonds:
- attraction due to shared electrons
- ex. water
Water Is Covalent
Electron pair
forms covalent
bond
Each spends
some time
w/one, then
the other
atom
Oxygen Molecule (O2)
Oxygen Atom
Oxygen Atom
2. Ionic Bonds:
- attraction due to electrons transferred
from one atom to another creating
+ and - ions
- ex. table salt (NaCl)
Ionic Bonding in NaCl
Sodium has 1
electron in outer
shell;
chlorine has 7.
Sodium can lose 1
electron;
Chlorine can gain 1
electron. Sodium
becomes a positive
ion; Chlorine a
negative ion.
Ionic Bonding in NaCl
Opposites
attract.
Sodiums
nestle
between
chlorines.
Perfectly
cubical
crystals.
Cl- Cl- Cl- ClNa+
Na+
Cl- Cl-
Na+
Na+
Cl- Cl-
Na+
Na+ - Na+ - Na+ Cl Cl - Cl ClCl- Cl- Cl
Na+ Cl
Na+
Na+
Na+
Na+
+Na
Cl
+Na
Cl
+Na
Cl
Cl-
Na-+ Cl
Na-+
Na+
Na+
Cl- Cl- Cl
+ - Na+ - Na+ Na+
Na
Cl Cl Cl ClNa+
Na+
Na+
Na+
Cl- Cl- Cl- ClNa+
Na+
Na+
Na+
Some Elements Are Molecular.
Hydrogen gas
One electron from each
hydrogen atom is
shared, forming a
single covalent bond
Oxygen gas
Two oxygen atoms
share four electrons,
forming a double bond
E. Acids, Bases, and pH
1.Acids:
+
- form H ions in solution
2.Bases:
- form OH- (hydroxide) ions in
solution
3.pH:
- measure of how acidic or
basic a solution is
- logarithmic scale
The pH Scale
Oven
Bleach
Sea
Cleaner
Water
Urine
Stomach
Orange
Baking
Acid
Juice
Soda
Lemon
Blood
Ammonia
Coffee
Juice
Hand Soap
Lime
Juice Vinegar
Water
0
1
2
3
4
5
6
7
8
9
10
11
12
13
Neutral
pH+ = pOH–
Increasingly Acidic
Increasingly Basic
14
Universal pH Indicator
II.Water
A.Water Is Polar
- water molecules have
positive and negative ends
Because oxygen (O) is more electronegative than hydrogen
(H), shared electrons are pulled closer to oxygen.
–
This results in a
partial negative
charge on the
oxygen and a
partial positive
charge on
the hydrogens.
Polar Covalent Bonds
in a Water Molecule
O
+
H
H
H 2O
+
II.Water
A.Water Is Polar
- hydrogen bonds form between
water molecules
Hydrogen Bonds between
Water Molecules
–
+
H
+
–
–
+
Hydrogen
bonds
H

+
–
A.Water Is Polar
- polarity gives special properties
How Polarity Makes
Water Behave
Strangely (3:52)
+
–
H
H
+
–
O
H
+
+
O
H
+
Hydrogen
Bonds
- solvent of life
Negative oxygen regions
of polar water molecules are
attracted to sodium ions (Na+).
–
Na
+
+
–
Positive hydrogen regions
of polar water molecules
cling to chloride ions (Cl–).
–
+
Na
+
Cl–
+ Cl
–
–
+
+
+
–
+
–
+
–
–
–
–
A Crystal of Table Salt
Dissolving in Water
- strong cohesion and adhesion
Water surface tension
Water
conducting cells
100 µm
Water is transported great
heights up the stem.
Cohesion among
Water Molecules
- strong cohesion and adhesion
Meniscus
Capillarity
Adhesion among Water Molecules
- high specific heat
- good evaporative coolant
- less dense when frozen
Hydrogen
bond
Ice
Hydrogen bonds are stable
Liquid water
Hydrogen bonds
constantly break and re-form
Ice: Crystalline Structure
and Floating Barrier
III. Organic Compounds
- Living organisms are made up of
organic compounds.
A.Major Differences Between:
Living vs. Nonliving
Systems
Systems
complex
compounds
high energy
simple
compounds
low energy
- All organic compounds contain carbon.
- Exceptions: CO2, CO, CaCO3
- Carbon can form 4 covalent bonds.
- Carbon based
molecules form
chains, branched
chains, rings, etc.
Chlorophyll A
Chlorophyll B
Buckminsterfullerene
B. 4 Classes of Organic
Compounds:
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic Acids
IV. Carbohydrates
- contain C, H, O (1:2:1)
- include sugars, starches, cellulose
- used for energy storage and to build
cell walls
- names usually end in "-ose"
A. Monosaccharides:
- single (simple) sugar
A. Monosaccharides:
- single (simple) sugar
- C6H12O6, C5H10O5
- ex. glucose (source of energy in cells),
fructose (fruit sugar), galactose
B. Disaccharides:
- double sugar
B. Disaccharides:
- double sugar
- C12H22O11
- ex. sucrose (table sugar), lactose
(milk sugar)
C. Polysaccharides :
C. Polysaccharides
- many sugars
1. Starch
- Made of many 10 - 1000
glucose molecules
- in plants (potatoes, grains)
- Glycogen: animal starch
Storage polysaccharides
of plants and animals
Chloroplast
Starch
Mitochondria
Glycogen
granules
0.5 m
1 m
Amylose
Amylopectin
Starch: a plant polysaccharide
Glycogen
Glycogen: an animal polysaccharide
2. Cellulose:
- long starch chains bonded side by side
- very strong
- found in the plant cell walls
The Arrangement of Cellulose
in Plant Cell Walls
Cell walls
Cellulose microfibrils
in a plant cell wall
Microfibril
About 80 cellulose
molecules associate
to form a microfibril, the
main architectural unit
of the plant cell wall.
0.5 m
Plant cells
Parallel cellulose molecules are
held together by hydrogen
bonds between hydroxyl
groups attached to carbon
atoms 3 and 6.
OH CH2OH
OH
CH2OH
O O
O O
OH
OH
OH
OH
O
O O
O O
O CH OH
CH2OH
OH
2
H
CH2OH
OH CH2OH
OH
O O
O O
OH
OH
OH O
OH
O
O
O O
O CH OH
CH
OH
2
2OH
H
CH2OH
OH
OH CH2OH
O O
O O
OH
OH
OH O
O OH
O O
O
O CH OH
OH CH2OH
2
H
 Glucose
monomer
Cellulose
molecules
A cellulose molecule
is an unbranched 
glucose polymer.
Starch and Cellulose Structures
H
O
C
CH2OH
H
4
H
OH
O
H
HO
H
OH
OH
 glucose
OH
C
H
H
CH2OH
HO
C
H
H
C
OH
H
C
OH
H
C
OH
H
H
OH
4
HO
H
O
OH
H
1
H
OH
 glucose
 and  glucose ring structures
CH2OH
CH2OH
O
HO
O
1
OH
4
O
O
4
1
OH
OH
OH
O
O
1
OH
CH2OH
CH2OH
O
4
1
OH
O
OH
OH
Starch: 1– 4 linkage of  glucose monomers
OH
CH2OH
O
HO
OH
1
O
4
OH
O
OH
CH2OH
OH
CH2OH
O
O
O
OH
OH
O
OH
CH2OH
Cellulose: 1– 4 linkage of  glucose monomers
OH
V. Lipids
- fats, oils, waxes, steroids
- not soluble in water
- more energy (calories) in lipids than
in carbohydrates
- energy storage, insulation, cell
membrane, coatings, and many
hormones
Glycerol
Triglycerides
3 Fatty Acids
.
Lipid Structure
Saturated vs. Unsaturated
Fatty Acids
Animal
fat
Vegetable
oil
What Are Trans Fatty Acids?
Carcinogenic
‘Natural’
Cell Membrane
Phospholipid Bilayer
Steroids
Cholesterol
Testosterone
Estradiol
Cortisol
Progesterone
Aldosterone
VI. Proteins:
- the most abundant and varied of
organic compounds
- contain C, H, N, O (S)
A. Types of Protein
1.Structural:
- keratin (hair, fingernails)
- collagen
2.Contractile:
- actin and myosin (muscle)
3.Pigments:
- melanin (in skin, hair, iris)
4.Hormones:
- regulate body functions (insulin)
5.Antibodies:
- fight disease
6.Enzymes:
- amylase (in saliva), lactase
B. Structure of Proteins
- very complex
1. Amino Acids
- building blocks of proteins
- 20 different amino acids
- proteins contain between
50 - 2000 amino acids
2. Peptide Bond
- joins 2 amino acids
- polypeptide: many amino acids
Peptide Bond
3. Levels of Protein Structure
Primary
Structure
Secondary
Structure
Tertiary
Structure
Quaternary
Structure
3. Levels of Protein Structure
a) Primary Structure:
- sequence of amino acids
b) Secondary Structure:
- helix or pleated sheet
c) Tertiary Structure:
- amino acids interact to
form the polypeptide
into a 3 dimension shape
d) Quaternary Structure:
- 2 or more tertiary
polypeptides
C. Enzymes
- protein catalysts
- speed up chemical reactions
- each enzyme catalyzes only one
specific substrate
- most function at a specific
temperature and pH
C. Enzymes
C. Enzymes
VII. Nucleic Acids
- 2 major types:
A.DNA
- contains
hereditary
information
(genes)
- double helix
VII. Nucleic Acids
- 2 major types:
A.DNA
- contains hereditary
information (genes)
- double helix
B. RNA
- controls protein synthesis
- single helix
DNA
RNA
Protein
Information
Flow:
The
End
NaCl Dissolved by Water
NaCl is
ionicly
bonded
Water is
polar and
charged
O sticks to
Na+
H sticks to
Cl-
ƒ2-6
Chapter 2
65
Universal pH Indicator
pH 5.0
pH 4.0
pH 7.0
pH 8.0
pH 6.0
pH 9.0
pH 10.0
Information Flow:
DNA
RNA
Protein