Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A Level Biology : Content > Topic 7A : Muscles & Respiration > Flashcards

Topic 7A : Muscles & Respiration Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

antagonistic pair of muscles

A

pair of muscles that creates movement when one contracts and the other relaxes eg flexors and extensors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

tendons

A

non elastic tissue connecting muscles to bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

ligaments

A

elastic tissue connecting bones to bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

flexors

A

contract to bend at joint (bicep)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

extensor

A

contract to extend at joint (tricep)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

joints

A

area where two or more bones attach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are joints made of

A

fibrous connective tissues and cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

cartilage

A

firm, flexible connective tissue which covers bone end at joint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

multinucleate

A

eukaryotic cells that have more than one nucleus per cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

myofilaments

A

filaments of myofibrils constructed from the proteins myosin and actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

sarcolemma

A

cell membrane of muscle fibre cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

sarcoplasmic reticulum

A

specialised endoplasmic reticulum of muscle that functions especially as a storage and releases calcium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

transverse (T) tubules

A

bits of the sarcolemma that folds inwards across the muscle fibre and stick into the sarcoplasm

these help spread electricL impulses throughout the sarcoplasm so they reach all parts of muscle fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

myofibrils

A

long, cylindrical organelles made up of proteins that make up muscle fibres and are specialised for contraction

made of many units called sarcomeres

contain bundles of thick and thin myofilaments that move past each other to make the muscles contract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

skeletal muscle

A

type of muscle people use for movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

slow twitch fibres

A

contract slowly

use for posture

good for endurance activities

can work for long tile without getting tired

energy released slowly (aerobic respiration)

lots of mitochondria and blood vessels to supply muscles with oxygen

reddish due to lots of myoglobin

less sarcoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

fast twitch fibres

A

contract very quickly

use for fast movement

good for short bursts of speed and power

get tired very quickly

energy released (anaerobic respiration) using glycogen

fee mitochondria/blood vessels

whitish due to less myoglobin

high sarcoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what determines the length of time a muscle contracts for

A

how long calcium ions remain in the sarcoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

myoglobin

A

protein similar to haemoglobin made of 1chain

much higher affinity for oxygen

readily accepts oxygen from blood

acts as an oxygen store in muscles and will only release it if oxygen concentration falls very low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

features of bones

A

strong and hard

very strong under compression forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

thick myofilaments (protein)

A

myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

thin myofilaments (protein

A

actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

z-line

A

ends of each sarcomere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

m-line

A

middle of each sarcomere (middle of myosin filaments)

25
Q

h-zone

A

contains only myosin filaments

26
Q

sliding filament theory

A

myosin and actin filaments slide over one another to make the sarcomeres contract

the simultaneous contraction of lots of sarcomeres means myofibrils and the muscle fibres contract

muscle relaxes, sarcomeres return to their original length

27
Q

what happens when muscles are at rest

A

tropomyosin held by troponin blocks the actin-myosin binding side so myofilaments cant slide past each other because myosin heads cant bind to the actin-myosin binding site on the actin filaments

28
Q

explain the process of how action potential affects muscle contraction

A

action potential stimulates a muscle cell and depolarises the sarcolemma and the depolarisation spreads down the T-tubules to the sarcoplasmic reticulum.

sarcoplasmic reticulum releases calcium ions which bund to troponin causing it to change shape which pulls the attached tropomyosin out of the actin myosin binding site, binding site is exposed allowing myosin head to bind.

an actin-myosin cross bridge is formed at this point.

calcium ions activate ATPase breaking down ATP to provide the energy required for muscle contraction

ATP also provides energy to break the cross bridge so the myosin head detaches from the actin filament, myosin head reattaches to different binding site forming a new cross bridge and the cycle repeats.

the constant formation and breakage of cross bridges causes the muscle to contract.

29
Q

what happens when excitation stops

A

calciums ions leave their binding sites on troponin and move to sarcoplasmic reticulum by active transport.

troponin returns to normal shape,pulling the attached tropomyosin with them meaning that tropomyosin block actin-myosin binding sites again.

muscles don’t contract as myosin heads don’t bind to the binding sites.

actin filaments are back to relaxed position which lengthens the sarcomere.

30
Q

why does rigor mortis occurs

A

the energy from ATP is needed to break the bonds between actin and myosin.

ATO is made during respiration in the mitochondria but death cells cant produce ATP.

this causes actin and myosin to be at a fixed position which leads ro muscles becoming stiff.

31
Q

aerobic respiration

A

process during large amount of energy is released by splitting glucose into carbon dioxide (waste) and hydrogen (which combines with atmospheric oxygen to produce water)

32
Q

what chemical reactions occur during aerobic respiration

A

glycolysis (phosphorylation and oxidation)

link reaction

krebs cycle

oxidative phosphorylation

33
Q

how many ATP molecules are produced during aerobic respiration

A

38

34
Q

site of glycolysis

A

cytoplasm

35
Q

what type of process is glycolysis

A

anaerobic

36
Q

explain phosphorylation as a part of the glycolysis process

A

glucose is phosphorylated by adding 2 phosphates from 2 ATP molecules.

this creates 2 molecules of triose phosphate and 2 ADP molecules.

37
Q

explain oxidation as a part of the glycolysis process

A

triose phosphate is oxidised (loses hydrogen) forming 2 pyruvate molecules (go into mitochondrial matrix for link reaction)

NAD collects hydrogen forming 2 reduced NAD (used in last stage)

4 ATP are produced but 2 are used up in stage one so the net gain is 2 ATP

38
Q

how many times does the link reaction and krebs cycle happen for each glucose molecules

A

2

39
Q

explain the link reaction as a part of aerobic respiration

A

pyruvate is decarboxylated (one carbon removed in the form of carbon dioxide).

NAD is reduced by collecting hydrogen from pyruvate, changing pyruvate into acetate.

acetate and coenzyme A combine to form acetyl coenzyme A

no ATP produced

40
Q

site of link reaction

A

mitochondrial matrix

41
Q

site of krebs cycle

A

mitochondrial matrix

42
Q

explain the krebs cycle as a part of the aerobic respiration

A

Acetyl CoA combines with oxaloacetate forming citrate and coenzyme A goes back to link reaction.

6C citrate molecule is converted to a 5C molecule and decarboxylation occurs as well as dehydrogenation, hydrogen is used to produce reduced NAD from NAD.

5C molecule converted to 4C, decarboxylation and dehydrogenation occurs again producing reduced FAD and 2 reduced NAD.

ATP produced by direct transfer of phosphate from an intermediate compound to ADP (substrate-level phosphorylation).

citrate converted to oxaloacetate

43
Q

how many carbon dioxide molecules does krebs cycle produce

A

2

44
Q

define oxidative phosphorylation

A

process where the energy carried by electrons, from reduced coenzymes (NADH and FADH) is used to make ATP.

the whole point of previous stages is to produce these for the final stage

45
Q

what two processes make up oxidative phosphorylation

A

electron transport chain and chemiosmosis

46
Q

what happens during electron transport chain as part of oxidative phosphorylation

A

hydrogen atoms released from NADH and FADH as they are oxidised to NAD and FAD, hydrogen atoms split into protons and electrons.

electrons move down the electron transport chain (made up of electron carriers), losing energy at each level.

this energy is used by electron carriers to pump protons from matrix into inter-membrane space.

concentration of protons is higher in intermembrane space than matrix which forms electrochemical gradient

47
Q

what happens during chemiosmosis as part of oxidative phosphorylation

A

protons move down the electrochemical gradient back into the matrix via ATP synthase which makes ATP from ADP and inorganic phosphate.

48
Q

what is the final electron acceptor

A

oxygen

49
Q

what combines to form water at the end of electron transport chain

A

protons, electrons and oxygen (from blood)

50
Q

what could happen if metabolic poisons are present

A

they target electron carriers preventing them from passing on electrons and chemiosmosis from happening so ATP is not produced.

51
Q

anaerobic respiration

A

the production of ATP without the need of oxygen.

52
Q

name the type of anaerobic respiration you need to know

A

lactate fermentation

53
Q

where does lactate fermentation occur

A

animals

54
Q

explain the process of lactate fermentation

A

glucose is converted to pyruvate via glycolysis and the reduced NAD from glycolysis transfers hydrogen to pyruvate to form lactate and NAD.

NAD can be reused in glycolysis.

production of lactate regenerates NAD meaning that glycolysis can continue even when there isn’t much oxygen around so a small amount of ATP can still be produced to keep biological processes going.

55
Q

what builds up after a period of time from lactate fermentation

A

lactic acid

56
Q

name two ways animals break down lactic acid

A

cells convert lactic acid to pyruvate which then reenters aerobic respiration at the Krebs Cycle.

liver cells convert lactic acid back to glucose which can be stored or respired.

57
Q

does bacteria carry out lactate fermentation

A

some do

58
Q

what is the purpose of aerobic respiration

A

to release energy for metabolic reactions

59
Q

I band

A

contains only action

short when contracting

long when relaxed

A Level Biology : Content (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions