Transcript from H - rkanatomy

The Chemistry
of Life
Anatomy and Physiology
Hierarchy of Structures
(Ex.)Rattlebox Moth
• Organ
– Ex. flight muscle
• Tissues
– Ex. muscle tissue
• Cell
– Ex. muscle cell
• Organelles
– Ex. myofibril
• Molecules
– Ex. actin and myosin
So, what elements make up
the molecules of life?
The Star
of the Show
Why Study Carbon?
• All of life is built on carbon
• Cells
– ~72% H2O
– ~25% carbon compounds
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•
•
•
carbohydrates
lipids
proteins
nucleic acids
– ~3% salts and trace elements
• Na, Cl, K…
Chemistry of Life
• Organic chemistry is the study of carbon
compounds
• Carbon atoms are versatile building blocks
– Forms 4 stable covalent bonds
– Can form large ring, chain, or branching chain
structures.
– Can form double and triple bonds between two
carbons
H
H
C
H
H
Valence electrons – are the electrons in the
outermost shell of an atom.
Valence – refers to the number of covalent bonds
an atom of an element can form:
C is 4
H is 1
O is 2
Ex. H2O, CH4, C2H2, C2H4
N is 3
4 types of Macromolecules
and our body gets them/builds them from food and
water
• Carbohydrates
• Lipids
• Proteins
• Nucleic acids
Macromolecules
compounds of life
Macro- means very, very LARGE
• carbon framework (organic)
• they are polymers made of repeating
subunits called monomers.
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–
–
–
poly means many
meros means part
mono means single
So what do the words polymer, monomer, and
macromolecule mean?
– Like “pearls on a necklace”
Carbohydrates are polysacharrides
These are all SUGARS
•
Monomers (subunits)
– Simple sugars a.k.a monosaccharides
FUNCTIONS
1) quick energy
a) starch in plants
b) glycogen in animals
2) structures such as
Glucose – simple
sugar made by plants
1) cellulose (plant cell walls)
during photosynthesis
2) chitin (exoskeleton of insects)
CH2OH
Simple & complex sugars
H
• Monosaccharides
– simple 1 monomer sugars
– glucose
• Disaccharides
– 2 monomers
– sucrose
• Polysaccharides
– large polymers
– starch
O
H
OH
H
H
OH
HO
Glucose
H
OH
Some Carbohydrates
(polymer “necklaces” made of monomer glucose “pearls”)
Proteins
• Monomer subunits
– Amino acids
– There are 20+
Here are a few of many, many functions:
1) Peptide Hormones regulate homeostasis
ex. Insulin
2) Structures ex. bone, hair, muscle, horns, webs
3) Enzymes – catalysts for biochemical reactions.
(lowers energy needed for reactions to start)
4) Genetic regulation (turns genes on and off)
5) Transport ex. hemoglobin in rbc carries O2
• Structure
Proteins
– monomer = amino acids
• 20 different amino acids
– polymer = polypeptide
• protein can be one or more polypeptide chains
folded & bonded together
• large & complex 3D molecules
hemoglobin
growth
hormones
Nucleic Acids
the information molecules
• Monomer subunits
– Nucleotides
• Function
Carries information
• Heredity
• Genes provide directions
to make proteins
Examples
DNA = deoxyribonucleic acid
RNA = ribonucleic acid
Nucleotides have three parts:
a phosphate, sugar, and a base
(A, G, C, T, or U)
Nucleic Acids
• Function:
– genetic material
• stores information
– genes
– blueprint for building proteins
» DNA  RNA  proteins
• transfers information
DNA
– blueprint for new cells
– blueprint for next generation
proteins
Lipids
• Lipids are composed of C, H, O
– long hydrocarbon chains (H-C)
• “Family groups”
– fats
– phospholipids
– Steroids
• Do not form polymers
– big molecules made of smaller subunits
– not a continuing chain
Lipids
- all have hydrophobic properties “water fearing”
Functions / examples:
1) Fats STORE energy
(these have “long-tail” fatty acids)
2) Steroids for hormonal regulation
Ex. estrogen and testosterone
3) Structures
Ex. phospholipids make up the cell membrane
Ex. waxes for waterproofing
- such as (a) cuticle on leaves (b) earwax
Saturated Fats
• All C bonded to H
• No C=C double bonds
– long, straight chain
– most animal fats
– solid at room temp.
• contributes to
cardiovascular disease
(atherosclerosis)
= plaque deposits
Unsaturated Fats
• C=C double bonds in
the fatty acids
– plant & fish fats
– vegetable oils
– liquid at room temperature
• the kinks made by double
bonded C prevent the
molecules from packing
tightly together
mono-unsaturated?
poly-unsaturated?
saturated vs. unsaturated
saturated
unsaturated
Phospholipids make
up the cell membrane
Phospholipids make
up the cell membrane
• Hydrophilic heads “attracted” to H2O
- they will “flip” outward
• Hydrophobic tails “hide” from H2O
- they will flip inward
Water (outside the cell)
bilayer
Water (inside the cell)
Another lipid: Steroids
• Structure:
– 4 fused C rings + ??
• different steroids created by attaching different
functional groups to rings
• different structure creates different function
– examples: cholesterol, sex hormones
cholesterol
MATCHING
Which group
A
represents
1) carbohydrates?
2) nucleic acids?
3) proteins?
B
4) lipids?
C
D