Bio - 9.1, 9.2, 9.3, 9.4

Question 1

circulatory system - definition

Answer 1

a system of blood vessels with a pump & valves to ensure one way flow in blood

Question 2

valves - definition

Answer 2

structures that the blood to flow in 1 direction

Question 3

oxygenated blood

Answer 3

• blood in the left-handed side of the heart
• come from the lungs
• contains oxygen (picked up from capillaries)
• red

Question 4

deoxygenated blood

Answer 4

• oxygen is taken up by cells that need it for RESPIRATION
• blood brought back to right-hand side of the heart
• travels to the lungs to get oxygen

Question 5

double circulatory - definition

Answer 5

a system in which blood passes through the heart TWICE in one complete circuit of the body

(eg.) mammals / birds / reptiles

Question 6

single circulatory - definition

Answer 6

a system in which where blood passes through the heart only once in a complete circuit

(e.g) fish - heart => gills => body => heart

Question 7

double circulatory system - advantages

Answer 7

1. higher pressure (faster delivery of oxygen & nutrients to body cells)
2. efficient oxygenation (passes through twice)

Question 8

process of blood

Answer 8

body => vena cava => right atrium => R.A contract => atrioventricular valve opens => right ventricle => RV contract => semilunar valve opens => LUNGS => left atrium => L.A contract => atrioventricular valve opens => left ventricle => L.V contracts => semilunar valve opens => aorta => body

Question 9

difference in muscle wall thickness - ventricles

Answer 9

• right is thinner than left ventricle
• right.V pumps to lung
• left.V pumps to body
• left has thicker

Question 10

septum - definition

Answer 10

• to separate the left and right side of the heart

Question 11

atrioventricular valve

Answer 11

• between atria and ventricular
• ensures blood flows in correct direction
• flaps
• inside the heart

(eg.) tricuspid valve => between R.A and R.V
(eg.) biscuspid = >between L.A and L.V

Question 12

semiventricular valves

Answer 12

• between ventricles & arteries
• prevent backflow from arteries to ventricle after blood is pumped out
• pocket-like cusps
• to outside the heart

(eg.) pulmonary valve => R.V to pulmonary artery
(eg.) aortic valve => L.V to aorta

Question 13

coronary arteries

Answer 13

• vessels that supplies heart with nutrients and oxygen

Question 14

coronary artery disease (CHD) - causes

Answer 14

• smoking
• high cholesterol
• lack of exercise

Question 15

coronary artery disease (CHD)- prevention

Answer 15

• exercise
• avoid saturated fats

Question 16

coronary artery disease (CHD) - treatment (medication / surgery)

Answer 16

medication
- statin (lower blood pressure)
- aspirin (reduces blood clot)

surgery
- coronary bypass
- angioplasty
- stent

Question 17

coronary heart disease (CHD) - process

Answer 17

cholesterol deposits from plaque => makes artery narrower & walls stiffer => increases blood pressure => blood clot forms (thrombosis) => some breaks away and blocks smaller blood vessels

Question 18

heart beats per min

Answer 18

60 - 75 beats

Question 19

how to measure pulse - surface of skin

Answer 19

• big tendons in neck
• inside wrist

Question 20

how to measure pulse - hospital

Answer 20

• ECG (electrocardiograph)
• little electrodes are stuck onto the person’s body
• recorded in a graph

Question 21

pulse - definition

Answer 21

relaxation and expansion of an artery

Question 22

artery - purpose

Answer 22

• heart to rest of body
• carries oxygenated blood
• flows AWAY from the heart
• pulses thru doesn’t flow smoothly

Question 23

artery - features

Answer 23

• small lumen
• thick elastic walls (pulses)
• thick muscles walls
• no valves (pressure produced pushes it forward)

Question 24

veins - purpose

Answer 24

• low pressure
• rest of body to heart
• carries deoxygenated blood
• carries blood TOWARDS heart

Question 25

veins - features

Answer 25

- large lumen - thin walls - thin, elastic muscle wall - valves (prevent backflow)

Question 26

3 types of blood vessels

Answer 26

1. artery 2. vein 3. capillary

Question 27

capillary - purpose

Answer 27

- connects arteries and veins - carries both oxygenated and deoxygenated blood - reaches every cell

Question 28

capillaries - features

Answer 28

- one cell thick (diffision) - large surface area - no valves - small lumen

Question 29

sizes - artery, veins

Answer 29

- arteriole => artery => aorta - venule => vein => vena cava

Question 30

why arteries need to be thicker than veins

Answer 30

- stretch and recoil = maintains smooth blood flow - withstand high pressure - helps blood push forward

Question 31

2 blood vessels in liver

Answer 31

1. hepatic artery 2. hepatic vein

Question 32

hepatic artery

Answer 32

- carries oxygenated blood to the liver from the aorta - from heart - heart (aorta) => liver

Question 33

hepatic vein

Answer 33

- carries deoxygenated blood away from the liver to the vena cava - from digestive system (liver can process food) - liver => heart (vena cava)

Question 34

how liver differs from other organs - blood supply

Answer 34

- dual blood supply (hepatic artery and hepatic vein) - liver processes nutrients & detoxifies blood before it goes to the rest of the body.

Question 35

3 types of blood

Answer 35

1. red blood cell (RBC) = erythrocyte 2. white blood cell = leucocyte 3. platelet = thrombocyte

Question 36

red blood cell (RBC)

Answer 36

- contains haemoglobin (oxygen) - is a protein and contains iron - no nucleus (carry more haemoglobin) - circular biconcave shape (more S.A) - tiny enough for capillaries

Question 37

white blood cells (WBC)

Answer 37

- fights pathogens & clears dead body cells - has nucleus - 2 types = phagocytes & lymphocytes

Question 38

platelets

Answer 38

- small fragments of cells - no nucleus - made in red bone marrow - blood clotting : provides a barrier against the entry of bacteria and viruses

Question 39

lobed nucleus - WBC

Answer 39

- multi-lobed (2-5 lobes) - high flexible = can squeeze through capillaries - phagocytosis = engulfs & digests pathogens

Question 40

non-lobed nucleus - WBC

Answer 40

- round or slightly oval - produce antibodies & coordinated immune response

Question 41

plasma

Answer 41

- pale yellow liquid - liquid part of blood - transport hormones (eg. adrenaline) -