Biochem exam 1

What are the four major macromolecules

proteins, nucleic acids, lipids and carbohydrates

proteins are polymers of —- ——-

amino acids

there are 20 different amino acids incorporated into proteins, hald of them are ——- and must be obtained from the diet

essential

five uses for proteins in the body

structural, enzymes, transport, defense, contractile

proteins can be modified by lipids, sugars and phosphates to make:

lipoproteins, glycoproteins, and phosphoproteins

The most important carbohydrate and a major source of fuel

glucose

What is the structure of glucose

a hexose sugar c6h12o6

What type of isomers of carbohydrates are utilizes in plants and animals

D isomers

carbohydrates can be monosaccharides, disaccharides and ——

polysaccharides

glucose, fructose, galactose and ribose are all examples of

monosaccharides

Maltose, sucrose and lactose are all examples of

disaccharides

maltose is made of

2 glucose

sucrose is made of

a glucose and a fructose

lactose is made of a

galactose and a glucose

glycogen, starch, cellulose and chitin are all examples of

polysaccharides

Nucleic acids are polymers of

nucleotides

Nucleic acids, DNA and RNA, store —- ——, direct protein synthesis and sometimes (RNA) act as enzymes

genetic information

All lipids can be formed in vivo from —- —— except essential fatty acids

acetyl CoA

most lipids are —- in water meaning they are nonpolar

insoluble

lipids can be classified as ——, —— or ——-

simple, complex or derived

tryglycerides are an an example of —- lipids

simple

phospholipids and glycolipids are — lipids

complex

fatty acids, steroids, fat soluble vitamins, ketone bodies and eicosanoids are all examples of —— lipids

derived

lipids play a role in: (6)

membrane, energy storage, cell signaling, fuel, vitamins and steroid hormones

cholesterol, glycolipids, and phospholipids are all —— components

membrane

triglycerides play a role in —— -storage

energy

eicosanoids are key for cell ——-

signaling

fatty acids and ketones help with

fuel

glucocorticoids, androgens and estrogens are important —— hormones

steroid

Trace elements like Iron, zinc, copper, Mn, Selenium, Iodine and Co are important for absorbtion, biochemical reactions and —- and —— can cause disease states

deficiencies and toxicities

water is a part of ——% of all molecules in the body

99

water makes up for between — and —% of total body weight

50 and 70

water is —- meaning there is a separation of charges within a molecule between two bonded atoms

dipolar

— bonds between water molecules contribute to structure

hydrogen

water can form hydrogen bonds with other —— molecules

polar

— and — compounds are soluble in water

ionic and polar

means water loving

hydrophillic

— substances are usually insoluble in water

nonpolar

means water fearing

hydrophobic

pH is the negative log of the —- —- concentration

hydrogen ion

the pH of pure water at 25C is —

7.0

Low pH values (less than 7) are —— (higher H+ ion concentration)

acidic

High pH values are —— means a lower concentration of H+ — blood pH is slightly alkaline at 7.4

basic

acids are proton ——

donors

bases are proton ——

acceptors

weak acids do or do not completely disassociate in water

do not

at hald neutralization pH= —- meaning there is an equal number of associated and dissasociated ions

pka (disassociation constant)

pKa is a measure of —- ——

acid strength

stronger acids more readily dissociate in water and they have —- pKa values compared to weaker acids.

lower

A buffer is a substance that —— change in the pH of a solution when an acid or base is added to the solution

minimizes

weak acids and their conjugate bases act as ——

buffers

Read for review: The role of Co2 in blood pH: carbon dioxide is constantly produced by the TCA cycle and transported to the blood/plasma then removed by the lungs, dissolved co2 in the blood (levels can change with breathing and metabolism) can act as a buffer if reacted with water. Co2 and water form carbonic acid in a reversible reaction to also create free hydrogen and bicarbonate ions — carbonic acid is our weak acid or buffer

n/a

respiratory acid base alkylation

n/a

How the kidney affects the buffer system

n/a

amino acids are organic compounds that contain both an ——- group (R-NH2) and a ——- group (R-COOH) where R is a variable side chain

amine, carboxylic acid

— was the first amino acid discovered and was initially found in asparagus juice

asparagine

is the simplest amino acid and the R group is a single hydrogen atom

Glycine

amino acids are —- where they are diploar and have both - and + charge on the same molecule

zwitterions

all amino acids have at least — pka values (for the COOH and NH3+) some have a third for the r group

2

amino acids and some r groups can act as —-

buffers

most amino acids are — (a property of asymmetry)

chiral

Only — amino acids are used as building blocks for animal proteins (other form can be found in bacterial cell walls or antibodies from microorganisms)

L

there are — canonical or standard amino acids

20

there are some nonprotein amino acids that are not incorporated into proteins like ornithine, citrulline (urea cycle intermediates), GABA (a neurotransmitter) and —- (essential for cats synthesized from cysteine)

taurine

— amino acids can be synthesized from the body

nonessential

— amino acids must be obtained from the diet

essential

— is an essential amino acid for cats

taurine

growing chickens cannot synthesize all of the —- and —- they need (so it is conditionally essential)

glycine and proline

Taurine is found in high levels in — and —— (not found in plants)

fish and meat

taurine is involved in many biological processes including conjugation of bile acids, calcium signalling, CNS and cardiovascular function and the development of the —-, skeletal muscle and CNS

retina

taurine deficiency in cats can lead to

retinal degeneration and blindness

Dilated Cardiomyopathy (—) was also observed in cats with low plasma taurine. Reproductive failure, growth reduction and skeletal deformities can also occur.

DCM

— amino acid catabolism yields pyruvate or intermediates in the TCA cycle

glucogenic

— amino acid catabolism yields either acetoacetate or one of its precursors (acetyl coA or aceotacetyl coA)

ketogenic

nonpolar or hydrophobic amino acids mainly have —— r groups and cluster inside protein structures and interact via hydrophobic interactions. They are crucial for protein folding and 3d protein structure (minimize negative interactions with water/aqueous env)

hydrocarbon

Hydrophilic amino acids have polar r groups where there is at least one heteroatom in the side chain with —- pairs available for hydrogen bonding. They will be found on the external surface of the protein.

electron

proteins in their primary structure are —- of the 20 standard amino acids.

polymers

the alpha carbon of the carboxyl group of one amino acid reacts with the alpha amino group of another to form a —- bond (in a dehydration synthesis reaction)

peptide

the amino acid at one end which contains a free amino group is the amino —- end or the N terminus.

terminal

the amino acid at the other end which contains a free carboxyl group is the — terminal end or the c terminus

carboxyl

the numbering of animo acids in a protein starts at the — terminus

N

hydroxylation of proline and lysine in — is important for proper — structure and function.

collagen

hydroxylation of proline requires — —

ascorbic acid (vitamin c)

deficiency of vitamin c leads to decreased collagen and signs of —-

scurvy

ascorbic acid is required in the diet of —, —- and ——

primates, guinea pigs and bats

desmosine and isodesmosine are formed from — residues in proteins and are prevalent in elastin (smooth muscle)

lysine

phosphorylation is a key regulator of protein activity, for example phosphoserine, phosphoserine, and phosphorene and they are important for —— —-

cell signalling

activation of proteins by carboxylation of glutamic acid residues is involved in the — —— or chelation of calcium ions

clotting cascade

amino acid sequence is —— protein structure

primary

the localized areas of structural arrangements including B sheets and a helixes are —— protein structure

secondary

the packing of secondary structures into a more complex three d shape is —- protein structure

tertiary

the interaction of multiple protein subunits is — protein structure

quaternary

a noncovalent intermolecular interaction between animo acids with polar R groups

hydrogen bonding

a noncovalent intermolecular interaction between amino acids with charged R groups

ionic bonding

a noncovalent intramolecular interactions between amino acids with nonpolar R groups

hydrophobic

Covalent bonding of intramolecular interactions include the disulfide bonds between 000

cysteines

Hydrogen bonding between backbone animo acids/along vertical axis forms a coil

alpha helix

adjacent protein chains held in a pleated structure by hydrogen bonding along the backbones

B pleated sheet

In tertiary structure protein folding, noncovalent interactions and covalent bonding stabilize the structure. Initial folding is guided by —— proteins that help other proteins fold properly

chaperone

misfolding in proteins can cause —-

pathologies