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Flashcards in MCAT Biology Flashcards 3 Deck (70):
1

Gases move from areas of ____ partial pressure to areas of ______ partial pressure.

Higher to LOWER

2

circular smooth muscle

The inner layer of smooth muscle in the wall of the digestive tract. When this, the tube diameter is reduced. Certain areas of the circular muscle are thickened to act as valves (sphincters).

3

Voltage Gated Sodium Channels

Big player in depolarization since it allows Na+ to flow into the cell.

4

Common bile duct

The duct that carries bile from the gallbladder and liver to the small intestine (duodenum).

5

Acrosome

A region at the head of a sperm cell that contains digestive enzyems which, when released during the acrosome reaction, can facilitate penetration of the corona radiata of the egg, and subsequently, fertilization

6

Anabolic processes ______ NADH, NADPH, and FADH2 and they _______ energy.

OXIDiZE, and require energy to continue.

7

How many ATP molecules do each NADH and FADH2 produce?

NADH=2-3 ATP, FADH2= 2ATP

8

Nucleus (Nervous system)

A cluster of cell bodies WITH IN the CNS

9

Seminal Fluid is secreted by three glands: _____, ____, and the _____

Seminal vesicles, the prostate gland, and the Bulbourethral glands.

10

What are B lymphocyte plasma cells?

They make and release antibodies which induce antigen phagocytosis

11

The ovum consists of two layers of cells: The outer one is the ________ and the inner layer is the _______

Corona Radiata, and the Zona Pellucda

12

What do we call cells that produce an Rh factor? Do they produce an antibody?

Rh+, they produce no antibody

13

What are the two main premises that Darwin argued

No two members of a species are exactly alike even if they have the same parents AND Some variations are advantages, giving the organism the chance to branch out into new environments and to enlarge its numbers

14

What do we call cells that do not have an Rh factor?

Rh-, lack antigen and produce an antibody

15

Prosthetic

non-proteinaceous

16

Greek: polys

many

17

Greek: hydros

water

18

Six carbon carbohydrate

Glucose

19

Kinase

enzyme that phosphorylates somethings

20

Globular Proteins

function as enzymes-pepsinhormones-insulinmembrane pumps and channels- Na/K pumptransporter and storagereceptors

21

Triacylglycerols

triglyceridesfats and oilsconstructed from glycerol that is attached to 3 fatty acids. FUNCTION IS TO STORE METABOLIC ENERGYPROVIDE THERMAL INSULATION AND PADDING

22

**Denatured

conformation disruptedlost most of its secondary, tertiary and quaternary structurevery often, when denaturing agent removed, protein spontaneously refolds to original structure

23

Conjugate Proteins

Proteins containing nonproteinaceous components

24

Steroids

four ringed structures, contain hormones Vitamin D and cholesterolREGULATE METABOLIC ACTIVITIES

25

Common nitrogenous bases in nucleotides

null

26

Allosteric interaction

modification of enzyme config. resulting from the binding of an activator or inhibitor at a specific binding site on the enzyme

27

Water

solvent in which chemical reactions take place.80 percent of cell's mass is due to water

28

Two types of proteins

Globular and Structural

29

Proteoglycans

mixture of proteins and carbohydrates. major component of extracellular matrix

30

Denaturing Agent- Urea

Force Disrupted- Hydrogen Bonds

31

Solvate

Water molecules surround a hydrophilic molecule.

32

Major function of steroids ***

regulate metabolic activities

33

Irreversible inhibitors

bind ccovalently to enzymes and disrupt their function. (a few bind nonconvalantly)ex: penicillin which binds to bacterial enzyme that assists in the manufacturing of peptidoglycan cell walls

34

Saturation kinetics

as relative conc. of substrate increases, rate of rxn increases but to a lesser & lesser degree until Vmax achieved.Vmax is proportional to enzyme conc. as individual substrates must wait in line for an open substrate as more substrate is added

35

Cofactor

required for enzymes to reach optimal activity-non-protein compound...can be coenxzymes or metal ions

36

*Many coenzymes are often...

vitamins or their derivatives

37

Starch comes in two forms

amylose and amylopectin

38

Ring form of Glucose

it has two anomers

39

Glycolipids

carbohydrates attached to 3 C glycerol and two fatty acids. also amphipathicFOUND IN ABUNDANCE IN THE MEMBRANCES OF MYELINATED CELLS COMPOSING THE HUMAN NERVOUS SYSTEM

40

Secondary Structures

Contribute to confirmation of protein. can be alpha helix or beta pleated sheets

41

Saturated Fatty Acids

possess only single carbon-carbon bonds

42

Residue

each amino acid in a polypeptide chain

43

Structural Proteins

made from long polymersmaintain and add strength to cellular and matrix structure. ex. collagen

44

Fatty acids

building blocks for most complex lipidslong chains of carbon that have carboxylic acid at one end

45

Proline

induces turns in the polypeptide that will disrupt both alpa helix and beta pleated sheet formation

46

10 amino acids

are essential, human cannot manufacture these have to be ingested directly

47

Minerals and their function

dissolved inorganic compounds inside and outside the cell-assist in tranpoting substance in and out of cell by creation of electrochemical gradients across membranesthey can combine and solidify to give strength to a matrix, such as hydroxyapatite in bondalso act as cofactors assiting enzyme or protein function

48

Reversible covalent modification

some enzymes are activated or deactivated by phosphorylation or the additin of some other modifier such as AMP. Hydrolyis almost always can removed modifier. Phosphorylation almost almost occurs in presence of protein kinase

49

*Basic structure of Carbs

C(H2O)also called sugars or saccharides

50

2 types of coenzyme

2 types:cosubstrates- reversibly bind to specific enzyme and transfer some chem. group to another substrate. It reverts to orginal form by another enzymatic rxn, which is what distinguishes it from normal substrates. ATP is an exampleProstheic group- remain covalently bound to enzyme throughout rxn

51

Unsaturated Fatty Acids

contain one or more carbon-carbon double bonds

52

Hydrogen Bond

Water can hydrogen bond and this allows it to stay at its liquid stage in cellular environment.

53

side chain

amino acids differ in side chains, often are the R group.side chain is also attached to alpha carbon

54

Quaternary Structure

when two or more polypeptide chains bind together, form quaternary structure of the protein.

55

Noncompetitive inhibitors

bind noncovalantly to an enzyme at a spot other than active site & change conformation of enzyme-commonly act on more than 1 enzyme-can NOT be overcome by substrate conc. increase-lower Vmax-do NOT lower enzymes affinity for substrate, thus Km remains the same

56

Major function of triglycerols ***

store metabolic energy, provide thermal insulation, and padding

57

*3 parts of nucletides

1) 5-C sugar2) Nitrogenous base3) phosphate group

58

Alpha glucose anomer

Hydroxyl group on the anomeric carbon- carbon # 1 and methoxy group- c # 6 are on opposite sides of the carbon ring.

59

Major function of some fatty acids (eicosanoids ***

serve as local hormones

60

**quarternary structure of proteins

2 or more polypeptide chains bind together and same 5 forces as tertiary

61

Denaturing Agent- salt or change in pH

Force Disrupted- Electrostatic Bonds

62

Animals can digest starch and glycogen but not

beta linkages of cellulose.

63

Positive cooperativity as related to allosteric regulation

phenomenon in which the first substrate changes the shape of an enzyme allowing other substrates to bind more easily

64

Where can glucose be absorbed against a conc. gradient?

certain epithelial tissues in digestive tract and proxiaml tubule of kidneyhow: 2ndary active transport down conc. gradient of Na

65

Given a complicated question regarding complicated chemicals, what does the "ase" imply? and why is it important?

enzyme, so know it contains nitrogen and subject to denaturization

66

Name 4 imp. nucleotides and their respective funct.

1) ATP- readily available energy2) cyclic amp- imp. component in many 2ndary messanger systems3 & 4) NADH & FADH2 - coenzymes in Krebs cycle

67

Nucleotides are composed of three components

1. five carbon sugar2. a nitrogenous base3. a phosphate group

68

Structure of fatty acids and how energy is released from them

long chains of carbons truncated at one end by a carboxylic acid (COOH)-energy liberated through oxidation of fatty acids->released large amounts of chemical energy for a cell

69

20 Common Acids are Split into 4 groups

Nonpolar R groupsPolar R groupsAcidic R groupsBasic R groups

70

What regulates blood sugar levels and how is it specialized?

liver. Liver cells are one of few cells capable of reforming glucose from glycogen and releasing it back into the blood stream