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Biology
Respiration
Energy
Features of ATP that make it suitable for its role as the universal energy
currency of cells
1 small ;
2 water soluble so can move around cell ;
3 immediate source of energy ; A immediate energy donor
4 ref. to hydrolysed ;
5 phosphate removed releases energy ;
6 30.5 kJ mol-1 ; A molecule of ATP releases 30.5 kJ
7 ATP splits to ADP and Pi ;
note ATP = ADP and Pi + 30.5 kJ gains mp6 and mp7
8 reversible ;
9 intermediate between, anabolic and catabolic reactions / energy yielding
and energy requiring reactions ;
10 high turnover ;
Anabolic reactions
Biology 1
, any two from:
idea of synthesis from smaller units
1 DNA replication / transcription ;
2 to, make / build up, (named) protein ;
3 to, make / build up, (named), lipid / triglyceride / phospholipid ;
4 to, make / build up, (named) carbohydrate / polysaccharide ;
5 phosphorylation ;
Why ATP is needed for protein synthesis
any two from:
1 unwinding DNA ;
2 activating (RNA) nucleotides ;
3 ref. to mRNA synthesis ;
4 peptide bond formation / joining amino acids ;
5 AVP ; e.g. post translation modification / amino acid activation / moving
ribosomes along mRNA / movement of mRNA
from nucleus
Aerobic respiration
Why actual amount of ATP is less than theoretical number
any two from:
1 ATP / energy, used to transport, pyruvate / reduced NAD / products of
glycolysis, into (named part of) mitochondria ;
2 some protons leak from intermembrane space ;
3 some energy lost as heat ;
4 glucose may not be completely broken down / some intermediates are
used in different metabolic processes ;
5 reduced NAD may be used for other (metabolic) reactions ;
Role of NAD and FAD in aerobic respiration
1 coenzymes ;
2 help / for, dehydrogenases / dehydrogenation (reactions) ;
3 ref. to glycolysis / link reaction / Krebs cycle ;
4 carry / transfer / transport / bring, hydrogens / H ;
5 to, ETC / inner mitochondrial membrane / crista(e) ;
Use of ATP in glycolysis
Biology 2
, any three from:
1 phosphorylates glucose
2 to make fructose (1,6) bi(s)phosphate ;
3 so glucose cannot leave the cell ;
4 activates / increases energy of / decreases stability of, glucose ;
molecules, other than coenzymes, that are found in the mitochondrial matrix
and explain their role in aerobic respiration
any three names plus explanations from:
1 pyruvate, for link reaction / to bind to coenzyme A / to make acetyl (CoA) /
to make reduced NAD / be dehydrogenated ;
2 oxaloacetate to, accept acetyl / make citrate ;
3 citrate to, make reduced NAD / be dehydrogenated ;
4 enzymes to catalyse, link reaction / Krebs cycle ;
5 oxygen to, accept electrons / accept protons / form water ;
6 water as a, solvent / medium for reactions ;
7 DNA / RNA, to make (named) respiratory, enzymes / proteins ;
how Pi is transported across the inner membrane of the mitochondrion into
the matrix
1 (Pi) by facilitated diffusion or through a protein, channel / carrier ;
2 Pi and H+ move together ;
3 (as) H+ ions diffuse (through ATP synth(et)ase / to matrix) ;
glucose to pyruvate to acetyl coA
any nine from:
1 glycolysis ;
2 glucose phosphorylated by ATP ;
3 to fructose (1,6-)bisphosphate ;
4 lysis / splits, to form 2
× triose phosphate ;
5 (triose phosphate) has hydrogen removed / is dehydrogenated / is
oxidised ;
6 reduced NAD formed ;
74
× ATP / net 2ATP, produced ;
Biology 3
, 8 ref. to substrate-linked phosphorylation ;
pyruvate produced
9 enters mitochondrial matrix ;
10 link reaction ;
11 decarboxylated / carbon dioxide removed ;
12 (pyruvate) has hydrogen removed / is dehydrogenated / is oxidised ;
combines with coenzyme A
Mitochondrial structure and function
1 (function is) to make ATP ;
2 ref. to double membrane / outer and inner membrane / envelope ;
inner membrane
3 folded / cristae, to increase / for large, surface area ;
4 has, ATP synthase / stalked particles ;
5 has, ETC / carrier (proteins) / cytochromes ;
6 (site of) oxidative phosphorylation / chemiosmosis ;
7 impermeable to protons ;
intermembrane space
8 has low pH / high concentration of protons ;
9 protons pumped into intermembrane space ;
10 proton gradient between intermembrane space and matrix
or
protons diffuse from intermembrane space to matrix ;
matrix
11 contains (co)enzymes for, link reaction / the Krebs cycle ;
outer membrane
12 permeable to, pyruvate / reduced NAD / oxygen ;
13 AVP ; e.g. ribosomes / DNA, involved in protein synthesis
advantages of linking ATP transport to ADP transport across the inner
membrane of the mitochondrion.
1 constant / sufficient / correct, supply / amount of, ADP / reactant ;
2 (so) ATP can continue to be made / so enough ATP can be made ;
Biology 4