BIOCHEM LEC

Question 1

Regulation of water balance

Answer 1

a. Hypothalamic mechanisms
b. Antidiuretic Hormone
c. Retention or excretion by the Kidneys

Question 2

which involves the inability to concentrate urine or adjust
to subtle changes in extracellular fluid osmolarity, results from the unresponsiveness of renal tubular osmoreceptors to ADH

Answer 2

Nephrogenic Diabetes Insipidus

Question 3

angle between two hydrogen atoms to the oxygen in H2O

Answer 3

105 degree

Question 4

molecule with electrical charge distributed asymmetrically about its structure

Answer 4

DIPOLE

Question 5

Slightly Positive Side of H2O

Answer 5

Hydrogen

Question 6

Slightly Negative Side of H2O

Answer 6

Oxygen

Question 7

Bicarbonate and other buffers normally maintain the pH of extracellular fluid between ____ and ___

Answer 7

7.35, 7.45

Question 8

Blood pH below 7.35

Answer 8

Acidosis

Question 9

blood pH above 7.45

Answer 9

Alkalosis

Question 10

Suspected disturbances of acid-base balance are verified by measuring the pH of __________________

Answer 10

arterial blood

Question 11

Water’s strong dipole is responsible for its high _____________________

Answer 11

dielectric constant

Question 12

the _______ the dielectric constant, the ________ the force of attraction between charged and polar species

Answer 12

Higher, Weaker

Question 13

enables water to dissolve many
organic biomolecules that contain functional groups

Answer 13

hydrogen bonding

Question 14

chemical species that forms bonds with electrophiles by donating an electron pair

Answer 14

Nucleophile

Question 15

electron rich molecules

Answer 15

nucleophile

Question 16

electron poor molecules

Answer 16

electrophile

Question 17

Nucleophilic attack by water typically results in the cleavage of the amide, glycoside, or ester bonds that hold biopolymers together

Answer 17

Hydrolysis

Question 18

catalyze the hydrolysis of proteins into their component amino acids

Answer 18

Protease

Question 19

catalyze the hydrolysis of the phosphoester bonds in DNA and RNA

Answer 19

nuclease

Question 20

strongest force that holds molecules together

Answer 20

Covalent Bonds

Question 21

contributes to stability & functional competence of molecules

Answer 21

Non- covalent Bonds

Question 22

most biomolecules are ______________

Answer 22

Amphipathic

Question 23

possess both charged or polar region and hydrophobic or non polar region

Answer 23

Amphipathic

Question 24

refers to the tendency of nonpolar
compounds to self-associate in an aqueous environment

Answer 24

hydrophobic interactions

Question 25

minimizes the disruption of energetically favorable interactions between and is therefore driven by the surrounding water molecules

Answer 25

self-association

Question 26

interactions between oppositely charged groups within or between biomolecules

Answer 26

Electrostatic Interactions

Question 27

arise from attractions between transient dipoles generated by the rapid movement of electrons in all neutral atoms

Answer 27

Van der Waals Forces

Question 28

PRoton Donors

Answer 28

Acids

Question 29

Proton acceptors

Answer 29

Bases

Question 30

_________ pH= high concentration of H+

Answer 30

Low

Question 31

_________ pH= low concentration of H+

Answer 31

High

Question 32

Normal Values for pH in blood

Answer 32

7.35- 7.45

Question 33

Normal Values for PaCO2 in blood

Answer 33

35-45mmHg

Question 34

Normal Values for PaO2 in blood

Answer 34

80-100mmHg

Question 35

Normal Values for HCO3 in blood

Answer 35

22-26mEq/L

Question 36

Oxygen saturation

Answer 36

95-100%

Question 37

low pH, High paCO2, High H2CO3, N HCO3

Answer 37

Respiratory Acidosis

Question 38

high pH, low paCO2, low H2CO3, N HCO3

Answer 38

Respiratory Alkalosis

Question 39

low pH, N paCO2, N H2CO3, low HCO3

Answer 39

Metabolic Acidosis

Question 40

high pH, N paCO2, N H2CO3, high HCO3

Answer 40

Metabolic Alkalosis

Question 41

Biologic systems are essentially _____________ and use chemical energy to power living processes

Answer 41

Isothermic

Question 42

is that portion of the total energy change in a system that is available for doing work

Answer 42

ΔG or Free Energy

Question 43

states that the total energy of a system, including its surroundings, remains constant.

Answer 43

First Law of Thermodynamics

Question 44

states that the total entropy of a system must increase if a process is to occur spontaneously

Answer 44

Second law of Thermodynamics

Question 45

is the extent of disorder or randomness of the system and becomes maximum as equilibrium is approached

Answer 45

Entropy

Question 46

If ΔG is negative, the reaction proceeds spontaneously with loss of free energy

Answer 46

Exergonic

Question 47

if ΔG is positive, the reaction proceeds only if free energy can be gained

Answer 47

Endergonic

Question 48

the breakdown or oxidation of fuel molecules

Answer 48

Catabolism

Question 49

the synthetic reactions that buildup substances

Answer 49

Anabolism

Question 50

both catabolism and anabolism

Answer 50

Metabolism

Question 51

organisms utilize simple exergonic processes; for example, the energy of sunlight (green plants), the reaction Fe2+ → Fe3+ (some bacteria)

Answer 51

Autotrophic

Question 52

organisms obtain free energy by coupling their metabolism to the breakdown of complex organic molecules in their environment

Answer 52

heterotrophic

Question 53

is the greatest quantitativesource of ~ in aerobic organisms. ATP is generated in themitochondrial matrix as O2 is reduced to H2O by electrons passing down the respiratory chain

Answer 53

Oxidative Phosphorylation

Question 54

A net formation of two ~ results from the formation of lactate from one molecule of glucose, generated in two reactions catalyzed by phosphoglycerate kinase and pyruvate kinase, respectively

Answer 54

Glycolysis

Question 55

One ~ is generated directly in the cycle at the succinate thiokinase step

Answer 55

The citric acid cycle

Question 56

act as storage forms of group transfer potential

Answer 56

Phosphagens

Question 57

defined as the removal of eectrons

Answer 57

Oxidation

Question 58

is defined as the gain of eectrons

Answer 58

reduction

Question 59

Enzymes invoved in oxidation and reduction are called

Answer 59

oxidoreductases

Question 60

Classifications of oxidoreductases

Answer 60

- Oxidases - Dehydrogenases - Hydroperoxidases - Oxygenases

Question 61

catayze the remova of hydrogen from a substrate using oxygen as a hydrogen acceptor.* They form water or hydrogen peroxide as a reaction product

Answer 61

Oxidases

Question 62

is a hemoprotein widey distributed in many tissues, having the typica heme prosthetic group present in myogobin, hemogobin, and other cytochromes

Answer 62

Cytochrome oxidase

Question 63

The action of the enzyme Cytochrome oxidase is blocked by

Answer 63

Carbon Monoxide, cyanide, and hydrogen sulfide

Question 64

contain flavin mononucleotide (FMN)or flavin adenine dinucleotide (FAD) as prosthetic groups.

Answer 64

Flavoprotein

Question 65

play an important roe in protecting the body against the harmful effects of reactive oxygen species (ROS)

Answer 65

Hydroperoxidases

Question 66

are iron-containing hemoproteins in which the iron atom oscillates between Fe3+ and Fe2+ during oxidation and reduction.

Answer 66

Cytochromes

Question 67

are highy reactive oxygen-containingmoecues such as peroxides, which are formed during norma metaboism, but can be damaging if they accumuate.

Answer 67

Reactive Oxygen Species

Question 68

have a variety of functions in metaboism; oxidases and dehydrogenases pay major roes in respiration;

Answer 68

Oxidoreductases

Question 69

protect the body against damage by free radicas; and oxygenases mediate the hydroxyation of drugs and steroids.

Answer 69

hydroperoxidase