CH.3 Biochemistry Flashcards
Chemistry of a carbon atom
4 valence electrons, can form four single covalent bonds and also able to form double or triple bonds
define hydrocarbon chain
a chain of carbon atoms that form bonds with multiple hydrogen atoms as well as other carbon atoms, forming a chain of carbon surrounded by hydrogen
define functional group
Group of atoms linked by strong covalent bonds that tends to behave as a distinct unit in chemical reactions with other atoms.
eg. hydroxyl, carboxyl, amino, methyl and phosphate
describe structure and function of carbohydrates
- contain a 1:2:1 ratio of carbon, hydrogen, oxygen
- they are polar
- used for cellular respiration(ATP), structural components(DNA,RNA,ATP), glycolipids, glycoproteins
- found in grains, legumes, fruit
types of carbs
Monosaccharides
- one monomer
- glucose, fructose, galactose
Disaccharides
- two monomers formed by dehydration
- sucrose, lactose, maltose
Polysaccharides
- many monomers
- starch, glycogen, cellulose
specify major elements of lipids
carbon, hydrogen, oxygen
very little amounts of oxygen, mainly C and H
most common form of lipid
fatty acid
Hydrocarbon chain with little oxygen
non-polar
define hydrophilic
able to mix with water
define hydrophobic
unable to mix with water
three types of lipids
Triglycerides
phospholipids
steroids
Triglycerides
3 fatty acid chains bound to glycerol by dehydration
function: protection, insulation, energy storage
Phospholipids
2 fatty acids attached to glycerol and phosphate group
polar head and non-polar tail
major component of phospholipid bilayer in cell membrane
Steroids
4 interlocking hydrocarbon rings, cholesterol is base for all steroids
functions: hormones, vitamin D, bile salts
saturated vs unsaturated fats
Saturated: single carbon bonds and solid at room temp.
Unsaturated: double carbon bonds, liquid at room temp.
Polyunsaturated vs monounsaturated fats
Polyunsaturated: 2+ carbon double bonds
Monounsaturated: 1 carbon double bond
why are carbs generally hydrophilic
they have polar OH groups
why are lipids generally hydrophobic
they have many non polar bonds
elements in protein molecules
C,H,O,N,S,P
C,H,O,N always present
S,P, sometimes present
structure of amino acids
carbon in middle surrounded by amino acid, side chain, carboxyl group, and H atom
how many different amino acids are there
20
what are the three types of amino acids based on number of them attached together
dipeptide - 2 amino acids
tripeptide - 3 amino acids
Polypeptide - 10+ amino acids
4 levels of structure of a protein molecule
primary- amino acids form polypeptide chain
secondary- formation of helix or sheets
tertiary- alpha helix and/or beta sheets fold to form a
compact globular molecule held together by
intramolecular bonds
quaternary- 2 tertiary structures combine, making a
functioning protein
major functions of protein and examples
- structural, collegen/keratin
- regulatory, pancreas(insulin and glucagon)
- contractile, actin and myosin
- Immunological, antibodies
- transport, hemoglobin transports oxygen
- catalytic, sucrase
structure of nucleic acids
C,H,O,N,P
Nucleotides are building blocks for nucleic acids
nucleotide structure
one or more phosphate groups, a pentose sugar, and a base (Adenine, Guanine, Thymine, Cytosine)
Nucleotides are building blocks for nucleic acids
nucleotide function
Nucleotides can be assembled into nucleic acids (DNA or RNA) or the energy compound adenosine triphosphate.
Replication / Transcription / Translation
what is ATP
high energy source
ribose sugar, adenine base, 3 phosphates
covalent bonds
help in muscle contractions, brining molecules into cells, and anabolic reactions
