week 6

Question 1

What does DNA stand for?

Answer 1

DeoxyriboNucleic Acid

Question 2

Where is it found?

Answer 2

in the nucleus, tightly packed

Question 3

What is it made of?

Answer 3

nucleotides

Question 4

DNA purpose

Answer 4

it is instructions to build proteins

Question 5

Components of DNA

Answer 5

nucleus -> chromosomes -> nucleosome strands -> chromatin -> double helix ->

Question 6

Parts of a chromosome

Answer 6

centromere, short arm, long arm, telomere

Question 7

Telomere

Answer 7

Protect

Often reduce after each replication

Question 8

Number of chromosomes

Answer 8

46 chromosomes

23 – Mum
23 – Dad

make 23 pairs

Question 9

DNA letters (4)

Answer 9

Adenine
Cytosine
Guanine
Thymine

Question 10

Types of chromosomes

Answer 10

22 - autosomes

1 - sex chromosome

Question 11

Genotype

Answer 11

gene which codes for a specific trait

Question 12

Phenotype

Answer 12

physical expression (appeartance)

Question 13

Alleles - trait names

Answer 13

variation on the same trait

• if 2 identical ‐ called homozygous
• if 2 different ‐ called heterozygous

Question 14

Alleles - trait types

Answer 14

dominant:
- appears more frequently than another trait
recessive:
- expressed only when genotype is homozygous

Question 15

Polygenic

Answer 15

> 1 gene contributing

Question 16

Monogenic

Answer 16

1 gene contributing

Question 17

Mutation

Answer 17

change in nucleotide sequence

usually detected & repaired

Question 18

Sex chromosomes

Answer 18

• females XX
• males XY (X from Mum, Y from Dad)
• X chromosomes larger -> more genes

Question 19

Diploid

Answer 19

2n (2 x 23 = 46 chromosomes)
‘double’
Non gametes

Question 20

Haploid

Answer 20

n (23 chromosomes)
‘single’
gametes

Question 21

Cell division (2 types)

Answer 21

mitosis: division of somatic (body) cells

meiosis: division of gamete (sex) cells
• eggs and sperm

Question 22

Mitosis

Answer 22

2 daughter cells
diploid
identical

asexual - for growth

Question 23

Meiosis

Answer 23

4 daughter cells
haploid
non identical

sexual - make gametes

Question 24

What is CVS and 3 components

Answer 24

cardiovascular system

heart
vessels
blood

Question 25

Layers of the heart wall - Myocardial layers

Answer 25

Epicardium Myocardium Endocardium

Question 26

What are the 4 cambers

Answer 26

right atrium left atrium right ventricle left ventricle

Question 27

What are the 4 valves

Answer 27

aortic valve tricuspid valve pulmonary valve mitral valve

Question 28

Coronary veins

Answer 28

superficial | empty into coronary sinus & right atrium

Question 29

Major vessels (label to and from)

Answer 29

``` inferior vena carva superior vena carva pulmonary artery pulmonary vein arch of the aorta carotid artery thoracic aorta abdominal aorta jugular vein subclavian vein ```

Question 30

Pressure

Answer 30

things move from high to low pressure - volume decrease pressure increase (& visa versa) - passive process

Question 31

Cardiac muscle

Answer 31

``` muscle needs an electrical stimulus to make it work - heart has its own ‘stimulator’ - automaticity - cardiac conduction system ```

Question 32

Sinoatrial (SA) node

Answer 32

the ‘pacemaker’ | in the wall of the right atrium

Question 33

Atrioventricular (AV) node

Answer 33

junction between atria and ventricles

Question 34

AV bundle

Answer 34

in the septum carries impulses to left and right bundle branches

Question 35

Purkinje fibres

Answer 35

distribute impulse through ventricles

Question 36

ECG stands for

Answer 36

ElectroCardioGram

Question 37

What does the ECG do?

Answer 37

measures electrical activity that accompanies | each heart beat

Question 38

Components of ECG's

Answer 38

P wave – atrial depolarisation QRS complex – ventricular depolarisation T wave – ventricular repolarisation

Question 39

Cardiac cycle

Answer 39

period between start of one heartbeat and the beginning of the next includes both contraction and relaxation of both atria and ventricles

Question 40

Phases of cardiac cycle

Answer 40

``` atrial systole (contraction) atrial diastole (relaxation) ventricular systole (contraction) ventricular diastole (relaxation) ```

Question 41

Cardiac cycle - rest

Answer 41

atrium pressure > ventricle AV valves open ventricle pressure < artery • SL valves shut

Question 42

Cardiac cycle - contraction (first and second sounds)

Answer 42

pressure in ventricle is higher than in atrium - AV valves shut to stop back flow first heart sound (lubb) - can only occur once ventricle has begun contracting and its pressure rises pressure in ventricle is higher than in artery SL valves will open to let blood out second heart sound (dubb) - can only occur once ventricle has begun to relax and its pressure drops

Question 43

Heart sounds (list 4)

Answer 43

S1 – close AV valves S2 – close SL valves S3 as ventricle fills S4 atrial systole

Question 44

Average heart rate + cardiac cycle

Answer 44

80-100 BPM 0.8 seconds (0.5-relaxation, 0.3-contraction)