b9

Question 1

circulatory system

Answer 1

a system of blood vessels with a pump (heart) and valves to ensure one-way flow of blood.

Question 2

single circulation

Answer 2

In fish, blood passes through the heart once in each complete circuit of the body.

Question 3

flow of a single circulation

Answer 3

Heart → gills → body → back to heart

Question 4

doble circulation

Answer 4

Heart → gills → body → back to heart

Question 5

advantage of double circulation

Answer 5

Allows higher pressure and more efficient delivery of oxygen to the body.

Question 6

atria

Answer 6

recieves blood

Question 7

ventricles

Answer 7

pump blood out

Question 8

septum

Answer 8

separates left and right side

prevents mixing of oxygenated and deoxygenated

Question 9

valves

Answer 9

prevent backflow of blood

Question 10

coronary arteries

Answer 10

supply oxygenated blood to heart muscle

Question 11

muscular wall

Answer 11

-thick
-pumps blood with force

Question 12

how the heart works

Answer 12

Atria contract ✔️
→ push blood into ventricles

Ventricles contract ✔️
→ pump blood out of heart

Valves close ✔️
→ prevent backflow

Question 13

monitoring heart activity

Answer 13

-ECG(measure electrical activity)

-Pulse rate(HBPM)

-listening valves(lub-dub)

Question 14

effect of physical activity on heart rate

Answer 14

heart rate increases during physical activity

Question 15

why heart rate increases during physical activity?

Answer 15

Muscles need more oxygen and glucose ✔️

More respiration ✔️

Heart pumps faster to deliver these ✔️

Question 16

coronary heart disease

Answer 16

caused by blockage of the coronary arteries, reducing blood flow to the heart muscle.

Question 17

risk factors of coronary heart diesease

Answer 17

Unhealthy diet (high fat) ✔️
Lack of exercise ✔️
Smoking ✔️
Stress ✔️
Genetic factors ✔️
Age and sex ✔️

Question 18

unhealthy diet CHD

Answer 18

fat builds up in artery walls

causes narrowing/blockage

Question 19

lack of exercise CHD

Answer 19

less energy used=fats accumulates

heart becomes less efficient

Question 20

smoking CHD

Answer 20

CO reduces oxygen transport

Question 21

stress CHD

Answer 21

-hormones raise heart rate
-can damage arteries over time

Question 22

genetic predisposition CHD

Answer 22

family history increases risk

Question 23

AGE CHD

Answer 23

risk increases as u get older

Question 24

gender

Answer 24

males are at higher rick than females

Question 25

prevention CHD

Answer 25

DIET EXERCISE

Question 26

diet

Answer 26

Reduce fat intake ✔️ Prevents buildup of fatty deposits

Question 27

exercise

Answer 27

Keeps heart healthy ✔️ Improves circulation ✔️ Reduces risk of blockage ✔️

Question 28

Arteries

Answer 28

carry blood away from heart

Question 29

Arteries

Answer 29

-thick muscular and elastic walls -withstand high pressure from heart pumping -Narrow Lumen -maintains high pressure -no valves -pressure high enough to keep blood flowing

Question 30

veins

Answer 30

carry blood toward heart

Question 31

veins structure

Answer 31

-thin walls -blood is under low pressure, so thick walls not needed -wide lumen -allows blood flow easily at low pressure -valves present -prevent backflow of blood

Question 32

capillaries structure

Answer 32

-walls one cell thick -very short diffusion distance -very narrow lumen -slows blood flow(more time for gas exchange) -many capillaries -large surface area for exchange

Question 33

what do capilaries do?

Answer 33

-allow exchange of substances between blood and tissues Oxygen and nutrients → into cells ✔️ Carbon dioxide and waste → into blood ✔️

Question 34

vena cava

Answer 34

→ brings deoxygenated blood to heart ✔️

Question 35

Aorta

Answer 35

Aorta → carries oxygenated blood away from heart ✔️

Question 36

pulmonary artery

Answer 36

heart → lungs ✔️ (deoxygenated)

Question 37

pulmonary vein

Answer 37

lungs → heart ✔️ (oxygenated)

Question 38

blood is made up of?

Answer 38

Red blood cells ✔️ White blood cells ✔️ Platelets ✔️ Plasma ✔️

Question 39

red blood cells functions

Answer 39

transport oxygen

Question 40

white blood cell

Answer 40

defend body against pathogens

Question 41

types of white blood cell

Answer 41

-lymphocytes -phagocytes

Question 42

lymphocytes

Answer 42

produce antibodies to destroy pathogens

Question 43

steps of lymphocytes

Answer 43

Pathogen enters body ✔️ Lymphocyte recognises it as foreign ✔️ Lymphocyte produces antibodies ✔️ Antibodies bind to the pathogen ✔️ Pathogen is destroyed ✔️

Question 44

phagocytes

Answer 44

engulf and digest pathogen

Question 45

steps of phagocytosis

Answer 45

Move towards pathogen ✔️ Surround it ✔️ Engulf it (take it inside) ✔️ Digest it using enzymes

Question 46

platelets

Answer 46

help in blood clotting to prevent blood loss and entry of pathogens.

Question 47

key role of clotting

Answer 47

help in blood clotting to prevent blood loss and entry of pathogens.

Question 48

plasma

Answer 48

transport substances around the body

Question 49

what does blood plasma carry

Answer 49

-blood cells -hormones -nutrients