respiration

Question 1

what are autotrophs?

Answer 1

organisms that are able to synthesise their own usable carbon compounds from CO2 in the atmosphere through photosynthesis

Question 2

what is the formula for glucose?

Answer 2

C6H12O6

Question 3

what are heterotrophs?

Answer 3

are organisms that require pre-made usable carbon compounds which from they get their food

Question 4

what is light energy transformed to from the sun?

Answer 4

into chemical potential energy

Question 5

what is respiration?

Answer 5

it’s the release of energy from living cells from the breakdown of organic molecules

Question 6

what is the main function of the mitochondria?

Answer 6

to synthesize ATP

Question 7

describe the inner phospholipid membrane of the mitochondria

Answer 7

folded (cristae), less permeable, site of the electron transport chain, location of ATP synthase enzymes

Question 8

describe the outer phospholipid membrane of the mitochondria

Answer 8

smooth, permeable to several small molecules

Question 9

describe the intermembrane space of a mitochondria

Answer 9

has a low pH due to the high conc of protons, the conc gradient across the inner membrane is formed during oxidative phosphorylation

Question 10

describe the matrix in the mitochondria

Answer 10

an aqeuous solution within inner membranes of the mitochondrian, contains ribosomes, enzymes and circular mt DNA

Question 11

label all the structures inside a mitochondria

Answer 11

matrix, ribosome, outer membrane, inner membrane, intermembrane space, cristae, mitochondrial DNA, granule

Question 12

how is the structure of a mitochondria aid the function?

Answer 12

• large SA because of cristae so more electron transport chains can be held on the membrane
• more active cells can have larger mitochondria with longer and tighter packed cristae

Question 13

what is the order of the 4 stages of aerobic respiration

Answer 13

glycolysis, link reaction, krebs cycle, oxidative phosphorylation

Question 14

what are the products gained from glycolysis?

Answer 14

2 pyruvate molecules, net gain 2 ATP, 2 NADH

Question 15

what reactants are needed for glycolysis

Answer 15

ATP, NAD, glucose

Question 16

what are the steps of glycolysis

Answer 16

1) (phosphorylation) of glucose by 2ATP to form fructose biphosphate
2) (lysis) happens and aplits into 2 triose phosphate molecules
3) (oxidation) H is removed from each TP and given to NAD to form NADH
4) (dephosphorylation) 4 phosphates are added to 4ADP’s to form 4ATP
5) the 2 TP is converted to 2 pyruvates

Question 17

what are the products of link reaction?

Answer 17

acetyl coA, CO2, NADH

Question 18

how does pyruvate move into the matrix from the cytosol?

Answer 18

when oxygen is available, pyruvate enters mt matrix through the double membrane of the mitochondria via active transport. requires a transport protein and small amount of ATP

Question 19

what happens during the link reaction?

Answer 19

pyruvate is oxidised by enzymes to produce acetate and CO2, requiring the reduction of NAD to NADH. combinatio with coenzyme A to form acetyl coenzyme A

Question 20

what does coenzyme A consist of and used for?

Answer 20

has a nucleotide and a vitamin. used in link reactions and supplies the acetyl group to the krebs cycle

Question 21

where does the krebs cycle take place?

Answer 21

in the matrix of the mitochondria

Question 22

outline the stages for krebs cycle

Answer 22

2 acetyl coenzyme A (2Cc enter -> adds onto oxaloacetate (4c) -> makes citrate (6c) -> coenzyme A released in this reaction -> citrate converted back to oxaloacetate through redox reactions

Question 23

how is oxalacetate regenerated from citrate?

Answer 23

decarboxylation of citrate (releases CO2 as waste gas) + oxidation of citrate which releases H atoms that reduce coenzyme NAD and FAD + substrate level phosphorylation which makes 1 ATP from ADP

Question 24

how many ATPS are created through aerobic respiration? and where do they come from

Answer 24

NADH x 10 -> 25 ATP
FADH x 2 -> 3ATP
ATP (glycolysis) -> 2 ATP
krebs cycle -> 2 ATP
total = 32 ATP

Question 25

where does oxidative phosphorylation take place?

Answer 25

takes place in the inner mitochondrial membrane

Question 26

what is the current model called for oxidative phosphorylation called?

Answer 26

the chemiosmotic theory