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Flashcards in Chapter 1 Deck (114):
1

hydrolysis

how most macromolecules are broken apart

2

dehydration

how most molecules are formed

3

lipid

any biological molecule that has low solubility in water and high solubility in nonpolar organic solvents

4

6 types of lipids

fatty acids, triacyglyceroles, phosopholipids, glycolipids, steroids and terpenes

5

fatty acids

long chains of carbons, COOH at the end

6

saturated fatty acids

contain only single carbon-carbon bonds

7

unsaturated fatty acids

1 or more C-C double bonds

8

fatty acid oxidation

liberates large amounts of chemical energy for a cell

9

fats reach cells as

fatty acids

10

triacylglyercols/triglycerides

3 Carbon backbone called glycerol, which is attached to 3 fatty acids

11

adipocytes

(fat cells), specialized cells whose cytoplasm contains almost nothing but triglycerides

12

phospholipids

glycerol backone, polar phospate group replaces one one of the fatty acid -- phosphate group at the opposite side of the glycerol

13

amphipathic

one end polar, one end non polar

14

glycolipids

1 or more carbohydrates attached to the 3 carbon glycerol backbone

15

steroids

4 ringed structures

16

terpenes

vitamin A

17

lipoproteins

how lipids are transported in the blood, have a hydrophobic core and a hydrophilic shell

18

proteins/poly peptides

chain of aminoacids, linked together by peptide bonds

19

essential amino acids

cannot be produced in the body (10 of them)

20

digested proteins

reach cells as single amino acids

21

primary structure

# and sequences of amino acids in a polypeptide

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alpha helix

single chain of AA twist itself into

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beta pleated sheet

AA chains lie along itself, lie parallel or antiparalled

24

secondary structure

alpha helix and beta sheets, contribute to the conformation of the protein, reinforced by hydrogen bonds between the carbonyl oxygen and the hydrogen on the amino group

25

teritary structure

3D shape formed when peptide chain curls and folds

26

5 forces that contribute to teritary structure

covalent disulfide bonds, electrostatic interaction, hydrogen bonds, van der Waals forces, hydrophobic side chains

27

quaternary structure

2 or more polypeptides bound together

28

proline

induces ftursn in the polypeptide disrupt both alpha helix and beta pleated sheet formation

29

denatured

when protein conformation is disrupted

30

globular proteins

enzymes, hormones, membrane pumps and channels, membrane receptors, osmotic regulators, intra and intercellular transport and storage

31

structural proteins

maintain and add strength to cellular and matrix structure

32

glycoproteins

proteins with carb groups attached

33

see nitrogen

think protein

34

cytochromes

proteins that require a prosthetic heme group in order to function

35

carbohydrates

made from carbon and water

36

six carbon carbohydrate

glucose

37

glucose

essentilaly all digested carbs reaching body cells have been converted to ____ by the the liver or enterocyes

38

alpha glucose

hydroxyl group on the anomeric carbon and the methoxy group are on opposite sides of the ring

39

beta glucose

hydroxyl group and methoxy group are on the same side of the carbon ring

40

enough ATP glucose is polymerized to the polysaccharide

glycogen or converted to fat

41

glycogen

found in all animal cells, large amounts in muscle and liver cells

42

liver cells

capable of reforming glucose from glycogen and releasing back into blood stream

43

cells capable of absorbing glucose against concentration gradient

certain epithelial cells in the digestive tract and the proximal tubule of the kidney (done via secondary active transport)

44

how cells absorb glucose

facilitated diffusion

45

without insulin only ____ and ___ are capable of absorbing sufficient amounts of glucose via facilitated transport system

neural and hepatic cells

46

plants form __ and ___ from glucose

starch and cellulose

47

types of startch

amylose and amylopectin

48

amylose

isomer of cellulose that may be ranched or unbranched, same alpha linkages as glycogen

49

amylopectin

resembles glycogen has a different branching structure

50

cellulose

beta linkages

51

most animals

only have enzymes to digest alpha linkages of starch and glycogen

52

nucleotides

5 carbon sugar, nitrogenous base, phosphate group

53

polymers of nucleotides

nucleic acids -- DNA and RNA

54

nucleotides joined together by

phosphodiester bonds btwn phosphate group of one nucleotide and 3rd carbon of the pentose of the other nucleotide forming long strands

55

nucleotides written

5' --> 3'

56

DNA

two strands joined together by hydrogen bonds to make double helix

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2 h bonds

adenine and thymine

58

3 h bonds

cytosine and guanine

59

DNA is written

top strand -- 5' --> 3' ; bottom strand 3' --> 5'

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RNA

single strand, uracil replace thymine

61

important nucleotides

ATP, cyclic AMP, NADH, FADH2

62

minearls

dissolved inorganic ions inside and outside the cell, assist transport of substances entering and exiting cells by creating electrochemical gradient, also act as cofactors

63

enzymes

globular proteins, act as catalyst, don't change eq of a reaction

64

substrates

reactants upon which an enzymes works

65

active site

position on the enzymes where substrate binds

66

enzyme-substrate complex

enzyme bound to substrate

67

enzyme specificity

enzymes only work on a specific substrate or group of closely related substrates

68

lock and key theory

active site of the enzyme (lock) has a specific shape that only fits a specific substrate (key)

69

induced fit

shape of enzyme and substrate altered upon binding

70

saturation kinetics

relative concentration, rate of rxn increases, to a lesser and lesser degree until Vmax is reached

71

Vmax

proportional to enzyme concentration,

72

Km

substrate concentration at which rxn rate = to 1/2 Vmax, doesn't vary when enzyme concentration is changed

73

temperature and pH and enzymes

optimal temp == 37 C , optimal pH depends on enzyme eg -- pepsin below 2, trypsin works best between 6 and 7

74

cofactor

non protein component that many enzymes need to reach optimal activity, coenzymes or metal ions

75

coenzymes

vitamins or their derivatives

76

irreversible inhibitors

bind covalently to enzymes and disrupt their function, toxic

77

competitive inhibitors

bind reversibly with covalent bonds to the active site, raise Km don't change Vmax

78

noncompetitive inhibitors

bind non-covalently to an enzyme at a spot other than the active site, change the conformation of the enzymes, don't resemble substrate, commonly act on more than one enzyme, lower Vmax, Km is the same

79

inactive form of an enzyme

zymogen or proenzyme, when specific peptide bonds are cleaved -- irreversibly activated

80

allosteric interactions

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

81

negative feedback / feedback inhibition

product downstream in a rxn comes back and inhibits enzymatic activity in an early reaction, shut down mechanism

82

positive feedback

product returns to activate the enzyme

83

allosteric regulation

feedback inhibitors bind to an enzyme and cause conformational change

84

allosteric inhibitors and activators

both exist, alter Km w/o changing Vmax

85

positive cooperativity

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

86

negative cooperativity

occurs as well

87

enzymes

"-ase"

88

lyases

catalyzes the addition of one substrate to a double bond of a second substrate

89

ligase

require energy from ATP

90

kinase

phosphorylates something

91

phosphotates

dephosphorylates something

92

metabolism

all cellular chemical reactions

93

respiration

energy acquiring stages

94

anaerobic respiration

respiration where oxygen is not required

95

glycolysis

glucose broken down into 2 3C molecules of pyruvate, 2 net molecules of ATP, 2 molecules of NADH, occurs in the cytosol

96

substrate level phosphorlyation

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

97

fermentation

anaerobic respiration, glycolysis, reduction of pyruvate to ethanol or lactic acid and oxidation of NADH back to NAD+

98

aerobic respiration

requires oxygen

99

products of glycolysis

move into matrix of a mitochondria, pyruvate and NADH pass via facilitated diffusion

100

inner mitochondrial matrix

less permeable, pyruvates moves in via facilitated diffusion, NADH require hydrolysis of ATP to move in

101

inside matrix pyruvate becomes

acetyl CoA, rxn produces NADH and CO2

102

Krebs Cycle

each turn produces 1 ATP, 3 NADH and 1 FADH2

103

ATP Production occurs via

substrate level phosphylation

104

metabolism of fats

fatty acids converted into acyl CoA, brougth into matrix, acetly CoA produced, produces FADH2 and NADH for every 2 C of the original fatty acid

105

metabolism of proteins

AA deminated in liver, this product is converted to pyruvic acid or acetyl CoA or it may enter Krebs cycle at various stages

106

Electron transport chains

proteins in the inner membrane of mitochondria

107

1st protein complex

oxidizes NADH by accepting its high energy electron, electrons passed down series

108

Electrons passed down

ultimately accepted by oxygen to form water,

109

proton motive force

protons are pumped into intermembrane space for each NADH as electrons are passed along,

110

ATP synthases

protons propelled through this to produce ATP

111

Oxidative phosphorylation

uses energy released by the oxidation of products to create ATP

112

pH of intermembrane space

lower than that of the matrix

113

glucose + oxygen

carbon dioxide and water, combustion reaction

114

Amount of ATP Made in total

36 ATP