Mcat Biology

Front 1

What are the six major groups of lipids?

Back 1

fatty acids, triacylglycerols, phospholipids, steroids, terpenes, and glycolipids

Front 2

fatty acids

Back 2

long chains of carbons truncated at one end by a COOH

Hint 2

usually even number of carbons
max # is 24 carbons
saturated/unsaturated
reach cells in this form

Front 3

triacylglycerols

Back 3

three carbon backbone (glycerol) attached to three fatty acids

Hint 3

store energy, insulate, pad
adipocytes contain triglycerides

Front 4

adipocytes

Back 4

fat cells whose cytoplasm contains almost nothing but triglycerides

Front 5

phospholipids

Back 5

glycerol backbone, two fatty acids, one phosphate group

Hint 5

amphipathic

Front 6

steroids

Back 6

four ringed structures

Hint 6

include hormones, vitamin d, cholesterol, etc
regulate metabolic activities

Front 7

beta pleated sheets

Back 7

single polypeptide chain that lies along side itself
can be parallel or antiparallel

Front 8

five forces that create the Tertiary Structure

Back 8

1. covalent disulfide bonds between two cysteines
2. electrostatic (ionic) interactions between basic and acidic side chains
3. hydrogen bonds
4. van der waals forces
5. hydrophobic side chains

Front 9

On the MCAT, when you see nitrogen in a structure, think _________.

Back 9

PROTEIN

Front 10

carbohydrates

Back 10

made from carbon and water
have empirical formula : CH2O

Front 11

All digested carbohydrates reaching body cells have been converted to ________ by the _______ or _________, which are the small columnar epithelial cells found in the small intestine lining

Back 11

glucose
liver
enterocytes

Front 12

anomer

Back 12

cyclic stereoisomer

Hint 12

example : alpha and beta glucose

alpha glucose has hydroxyl group on one end (on carbon1) and methoxy group on opposite end (on carbon6)

beta glucose has both on same side of the carbon ring

Front 13

glycogen

Back 13

branched glucose polymer with alpha linkages

Hint 13

large amounts found in muscle and liver cells

Front 14

______ cells are one of the few types capable of reforming glucose from glycogen

Back 14

liver

Front 15

Plants don't form glycogen, but instead form _________ and __________ from glucose

Back 15

cellulose and starch

Front 16

nucleotide structure

Back 16

three components : five carbon sugar (pentose), nitrogenous base, phosphate group

Hint 16

examples : ATP, cAMP, NADH and FADH2 (coenzymes)

Front 17

phosphodiester bonds are formed between what to structures of nucleotides?

Back 17

between the phosphate group of one nuclotide and the 3rd carbon of the pentose of the other nucleotide

Hint 17

written as 5' --> 3'

Front 18

Minerals

Back 18

dissolved inorganic ions

Hint 18

create electrochemical gradients which assists in the transport of substances entering and exiting the cell

can combine and solidify to give strength
can act as cofactors (iron in heme)

Front 19

the enzyme substrate complex

Back 19

an enzyme bound to the substrate

Front 20

cofactors

Back 20

minerals or coenzymes that help enzymes reach their optimal activity

Hint 20

coenzyms are vitamins (essential organic molecules) or their derivatives

Front 21

coenzymes

Back 21

vitamins or their derivatives

Front 22

irreversible inhibitors

Back 22

agents which bind covalently to enzymes and disrupt their function

Hint 22

tend to be highly toxic

Front 23

competitive inhibitors

Back 23

compete at active site

Hint 23

generally only block active site for a fraction of a second

Front 24

noncompetitive inhibitors

Back 24

bind to a spot other than the active site and change conformation of enzyme

Front 25

feedback inhibition / negative feedback

Back 25

when one of the products downstream in a reaction series comes back and inhibits the enzymatic activity in an early reaction

Hint 25

- most enzymes work through this. - other proteins also undergo this regulation, such as hemoglobin
- done through allosteric regulation

Front 26

positive cooperativity (in terms of enzyme regulation)

Back 26

the first substrate changes the shape of the enzyme allowing other substrates to bind more easily

Front 27

lyase vs ligase

Back 27

lyases are enzymes that catalyze the breaking of various chemical bonds other than by hydrolysis or oxidation often forming a double bond or ring structure. lyases do not require energy. ligases are enzymes that join two molecules together and require energy.

Front 28

kinase vs phosphatase

Back 28

kinase phosphorylates, phosphatase dephosphorylates

Front 29

glycolysis

Back 29

breaks glucose into two 3C pyruvates. produces 2 ATP and 2 NADH

Front 30

substrate level phosphorylation

Back 30

formation of ATP from ADP and inorganic phosphate using the energy released from the decay of high energy phosphorylated compounds as opposed to using the energy from diffusion

Front 31

Krebs cycle

Back 31

each turn produces 1 ATP, 3 NADH, and 1 FADH2. substrate level phosphorylation.

Front 32

aerobic respiration net ATPs

Back 32

36 ATPs

Front 33

glycolysis net products
krebs net products

Back 33

g: 2 ATPs, 2 NADH
k: 2 ATPs, 6 NADH, 2 FADH2

Front 34

respiration overally equation

Back 34

glucose + O2 --> CO2 + H2O