respiration

Question 1

explain why all life needs to perform respiration

Answer 1

respiration breaks down organic molecules to release energy in bonds.
used to form ATP to perform metabolic activities to live

Question 2

why is ATP better source of energy for metabolic reactions than glucose

Answer 2

ATP -> ADP is a single-step process. energy is immediately available and releases small enough amounts of energy to prevent large amounts of surplus energy.
glucose is not immediate source of energy - first oxidised and energy used to form ATP

Question 3

4 metabolic activities that require ATP

Answer 3

active transport
anabolic reactions - such as synthesis of proteins
movement cilia or flagella
contractile filament movements in muscle cells

Question 4

site of glycolysis

Answer 4

cytoplasm

Question 5

molecules required for glycolysis

Answer 5

glucose, 2NAD, 2ADP + 2Pi

Question 6

products from glycolysis

Answer 6

2 reduced NADH, net gain of 2ATP, 2 pyruvate

Question 7

fate of the products from glycolysis

Answer 7

reduced NAD is used to produce more ATP
pyruvate also split up further to drive more ATP synthesis

Question 8

define substrate level phosphorylation

Answer 8

synthesis of ATP by transfer of phosphate group from another molecule

Question 9

define dehydrogenation

Answer 9

the removal of a hydrogen atom

Question 10

site of the link reaction

Answer 10

mitochondrial matrix

Question 11

molecules required for link reaction

Answer 11

2 pyruvate, 2NAD, coenzyme A

Question 12

products of link reaction

Answer 12

2 acetyle coenzyme A, 2 reduced NADH, 2CO2

Question 13

fate of the products of the link reaction

Answer 13

two acetyl groups are delivered to Kreb’s cycle as Acetyle CoA

Question 14

define decarboxylation

Answer 14

removal of carbon dioxide

Question 15

define oxidative decarboxylation

Answer 15

removal of carbon dioxide as well as hydrogen

Question 16

site of the Krebs cycle

Answer 16

matrix of mitochondrion

Question 17

molecules required for Krebs cycle

Answer 17

acetate, NAD, FAD

Question 18

products from Krebs cycle

Answer 18

CO2, reduced NAD, reduced FAD

Question 19

fate of the products of the Krebs cycle

Answer 19

reduced NAD and reduced FAD go on to oxidative phosphorylation

Question 20

summary of the products of glycolysis, link reaction and the krebs cycle for one molecule of glucose

Answer 20

4ATP, 6CO2, 10 reduced NAD, 2 reduced FAD

Question 21

name 3 coenzymes involved in respiration

Answer 21

conezyme a
NAD
FAD

Question 22

describe the role of coenzyme a

Answer 22

delivers acetate to Kreb’s cycle

Question 23

describe the role of NAD and FAD

Answer 23

accept protons and electrons released in the breakdown of glucose

Question 24

define oxidative phosphorylation

Answer 24

the synthesis of ATP by phosphorylation of ADP for which energy is obtained by electron transport and which takes place in the mitochorndria during aerobic respiration

Question 25

define electron carrier

Answer 25

proteins that accept and release electrons

Question 26

define electron transport chain

Answer 26

a series of complexes that transfer electrons from electron donors to electron acceptors

Question 27

defiene redox reactions

Answer 27

reaction in which both oxidation and reduction occurs

Question 28

what is the chemiosmotic theory

Answer 28

the synthesis of ATP driven by a flow of protons across a membrane

Question 29

site of oxidative phosphorylation

Answer 29

membranes of christae in mitochondria

Question 30

describe the role of christae in oxidative phosphorylation

Answer 30

larger membrane surface area for chemiosmosis - many ATP synthase enzyme in the membrane

Question 31

molecules required for oxidative phosphorylation

Answer 31

NADH and FADH

Question 32

products from oxidative phosphorylation

Answer 32

Water, ATP

Question 33

fate of the products from oxidative phosphorylation

Answer 33

ATP used in metabolic reactions, water excreted

Question 34

two sites of chemiosmosis in cells

Answer 34

mitochondria (chistae) and chloroplasts (thykaloid membranes)

Question 35

how is a proton gradient is produced in chemiosmosis

Answer 35

protons pumped across membrane using energy released from electron transport chain = higher concentration of protons on one side. Proton gradient forces protons to diffuse through the ATP synthase.

Question 36

which enzyme produces ATP in chemiosmosis

Answer 36

ATP synthase

Question 37

compare the source of electrons for chemiosmosis in photosynthesis and respiration

Answer 37

photosyntheis - excited electrons from photosystems respiration - reduced NAD and FAD

Question 38

compare the location for chemiosmosis in photosynthesis and respiration

Answer 38

photosynthesis - across thykaloid membrane respiration - christae

Question 39

what is a similarity of chemiosmosis in photosynthesis and respiration

Answer 39

both use the energy from electron transport chain to pump protons across membrane

Question 40

define anaerobic respiration

Answer 40

respiration in the absence of oxygen

Question 41

define obligate anaerobe

Answer 41

organisms that cannot live in environments containing oxygen

Question 42

define obligate aerobe

Answer 42

organisms that only respire aerobically

Question 43

define facultative anaerobe

Answer 43

organisms that can respire both aerobically and anaerobically

Question 44

define fermentation

Answer 44

anaerobic respiration without the involvement of electron transport chains

Question 45

define alcoholic fermentation

Answer 45

fermentation that results in the production of ethanol

Question 46

define lactate fermentation

Answer 46

fermentation that results in the proudction of lactate

Question 47

name the types of fermentation different types of cell can do

Answer 47

fungi and plant cells - alcoholic fermentation animal cells - lactate

Question 48

describe the usefulness of anaerobic respiration

Answer 48

when there is not sufficient oxygen for aerobic respiration to keep up with energy demands - anaerobic respiration can continue to provide ATP to carry out metabolic processes