Biology Topic 7 Key Words

Front 1

flex

Back 1

muscles contract to bend the joint

Front 2

extend

Back 2

muscles contract to straighten joint

Front 3

antagonistic

Back 3

muscles can only pull not push so at least two muscles are needed to move a bone to and fro

Front 4

extensor

Back 4

muscle that contracts to cause the extension of the joint

Front 5

flexor

Back 5

muscle that contracts to cause the flexing of the joint

Front 6

synovial fluid

Back 6

found in the cavities of synovial joints and prevents friction during movement

Front 7

ligaments

Back 7

fibrous tissue that connects bones to other bones

they control and restrict the amount of movement in the joint

Front 8

tendons

Back 8

attach muscle to bones

enables the muscle to power joint movement

Front 9

cartilage

Back 9

protects bones within joints

Front 10

muscle fibres

Back 10

each fibre is a single muscle cell

muscle is made up of bundles of muscle cells

Front 11

multinucleate

Back 11

each cell has several nuclei

Front 12

myofibrils

Back 12

within a muscle fibre

made up of sacromeres

Front 13

sacromere

Back 13

made up of two types of protein molecules - actin and myosin

contractions are brought about by the co-ordinated sliding of these protein filaments within the muscle cell sacromeres

Front 14

troponin and tropomysin

Back 14

protein molecules that actin is also associated with

Front 15

sliding filament theory

Back 15

myosin heads attach to the actin and dip forward , sliding the actin over the myosin

Front 16

neuromuscular junction

Back 16

connects nervous system to the muscular system

Front 17

sarcoplasmic reticulum

Back 17

a system of membrane-bound tubules that surrounds muscle fibrils, releasing calcium ions during contraction and absorbing them during relaxation

Front 18

Basal metabolic rate (BMR)

Back 18

measure of the minimum energy requirement of the body at rest to fuel basic metabolic processes

Front 19

respiration

Back 19

series of enzyme-controlled reactions

Front 20

glycolysis

Back 20

initial stages of carbohydrate breakdown

Front 21

pyruvate

Back 21

3 Carbon compound produced through the oxidation of intermediate 3C sugar

Front 22

Coenzyme NAD

Back 22

non-protein organic molecule

removes and takes up two hydrogen molecules

Front 23

substrate-level phopsphorylation

Back 23

phosphate from the intermediate compound is transferred to ADP, creating ATP

energy formation of ATP comes from the substrates

Front 24

The link reaction

Back 24

forms an important link between the metabolic pathways of glycolysis and the citric acid or Krebs cycle

Front 25

decarboxylated

Back 25

carbon dioxide released as waste product

Front 26

dehydrogenated

Back 26

two hydrogens removed and taken up by coenzyme NAD

Front 27

acetyl coenzyme A (acetyl CoA)

Back 27

2-Carbon molecule combines with the coenzyme A to form acetyl coenzyme A

Front 28

Krebs cycle

Back 28

the central metabolic pathway in all aerobic organisms. The cycle is a series of eight reactions that occur in the mitochondrion.

Front 29

FAD

Back 29

takes up hydrogens in krebs cycle

Front 30

electron transport chain

Back 30

electrons passed along chain of electron carriers in the inner mitochondrial membrane

Front 31

electrochemical gradient

Back 31

a gradient of electrochemical potential, usually for an ion that can move across a membrane.

Front 32

oxidative phosphorylation

Back 32

metabolic pathway in which the mitochondria in cells use their structure, enzymes, and energy released by the oxidation of nutrients to reform ATP.

Front 33

lactate

Back 33

what pyruvate is reduced into at the end of glycosis

Front 34

oxygen debt

Back 34

excess oxygen requirement

Front 35

what is oxygen also known as?

Back 35

post-exercise oxygen consumption

Front 36

creatine phosphate

Back 36

substance stored in muscles that can be hydrolysed to release energy

this energy can be used to regenerate ATP from ADP

Front 37

aerobic capacity

Back 37

the ability to take in, transport and use oxygen

Front 38

VO2 (max)

Back 38

the litres we consume a minute during exercise - 3-6 litres

Front 39

VO2

Back 39

volume per minute of oxygen we consume which is 0.2-0.3 at rest

Front 40

cardiac output

Back 40

volume of blood pumped by the heart in a minute

Front 41

stroke volume

Back 41

volume of blood ejected from left ventricle

Front 42

venous return

Back 42

during exercise there is greater muscle action, so more blood returns to the heart

Front 43

myogenic

Back 43

heart muscle is myogenic

muscles that can contract without external nervous stimulation

Front 44

sinoatrial node (SAN)

Back 44

small area of specialised muscle fibres located in the wall of the right atrium

Front 45

what is the sinoatrial node also known as?

Back 45

the pacemaker

Front 46

atroventricular node (AVN)

Back 46

area of specialised cells in wall of ventricles

Front 47

Purkyne fibres

Back 47

large, specialised muscle fibres that conduct impulses rapidly to the inner cells of the ventricles

Front 48

Bundle of his

Back 48

right and left bundles of fibres collectively

Front 49

electrocardiogram (ECG)

Back 49

electrical activity of the heart can be detected and displayed on this machine

most common test to check for problems with the heart

Front 50

P wave

Back 50

depolarisation of the atria, leading to atrial contraction (atrial systole)

Front 51

PR interval

Back 51

the time taken for impulses to be conducted from the SAN across the atria to the ventricles through the AVN

Front 52

QRS complex

Back 52

wave of depolarisation resulting in contraction of the ventricles (ventricular systole)`

Front 53

T wave

Back 53

repolarisation (recovery) of the ventricles during the heart's relaxation phase (diastole)

Front 54

cardiovascular control centre

Back 54

part of the brain that controls heart rate

Front 55

autonomic nervous system

Back 55

nervous system that you have no control over

Front 56

sympathetic nerve

Back 56

nerve going from cardiovascular control centre to the heart - accelerator

Front 57

vagus nerve

Back 57

nerve going from cardiovascular control centre to the heart - decelerator

Front 58

what type of nerve if the vagus nerve?

Back 58

parasympathetic nerve

Front 59

Adrenaline

Back 59

hormone that comes from the adrenal glands in the kidney

they affect the heart rate and sinoatrial node, increasing the heart rate

Front 60

tidal volume

Back 60

volume of air we breathe in and out each breath

Front 61

vital capacity

Back 61

maximum volume of air we can inhale and exhale

Front 62

minute ventilation

Back 62

volume of air taken into the lungs in one minute

Front 63

ventilation centre

Back 63

found in the medulla oblongata of the brain

controls breathing

Front 64

slow twitch fibres

Back 64

fibres that make up the darker muscles in the legs and body

specialised for slower, sustained contraction and can cope with long periods of exercise

Front 65

myoglobin

Back 65

dark red pigment that gives slow twich muscles their colour

Front 66

fast twitch muscles

Back 66

the fibres that make up paler flight muscles

Front 67

Thermoregulation

Back 67

control of body temperature

Front 68

homeostasis

Back 68

maintenance of a stable internal environment

Front 69

effectors

Back 69

control mechanism which turns on or off

Front 70

vasoconstriction

Back 70

cold conditions - muscles in arteriole walls contract causing arterioles to contrict

reducing blood supply to surface capillaries

blood diverted through shunt vessel which dilates

blood flows further from the skin surface so less energy is lost

Front 71

vasodilation

Back 71

blood flows closer to surface for more enrgy lost

Front 72

natural killer cells

Back 72

found in blood and lymph

do not use specific antigen recognition but provide non-specific immunity against cells invaded by viruses

Front 73

Keyhole surgery

Back 73

repairs damaged joints or removes diseased organs through key holes

Front 74

arthroscopy

Back 74

keyhole surgery on joints

Front 75

prothesis

Back 75

artificial body part used by someone with a disability to enable them to regain some degree of normal function

Front 76

cruciate ligaments

Back 76

hinge joint held together by four ligaments

can be fixed through keyhole surgery

Front 77

transcription factor

Back 77

what the hormone receptor acts as when it switches enxyme synthesis on or off

Front 78

Erthropoitein

Back 78

peptide hormone produced naturally by the kidneys

stimulates the formation of new red blood cells in bone marrow

Front 79

Testosterone

Back 79

steroid hormone produced in the testes by males and a small amount in the adrenal glands in both males and females