heart and blood

Question 1

what is the heart?

Answer 1

an organ that pumps blood around the body

Question 2

what is the purpose of the circulatory system?

Answer 2

to carry oxygen and nutrients to every cell and remove waste

Question 3

where does deoxygenated blood go?

Answer 3

right atrium - right ventricle - lungs

Question 4

where does oxygenated blood go?

Answer 4

left atrium - left ventricle - whole body

Question 5

why is the double circulatory system important?

Answer 5

it makes the circulatory system more efficient

Question 6

how many chambers does the heart have and what are they called.

Answer 6

4. right atrium, left atrium, right ventricle, left ventricle

Question 7

why is the muscle wall on the left ventricle thicker?

Answer 7

it has to pump blood at a high pressure around the whole body

Question 8

what are the 4 main blood vessels associated with the heart?

Answer 8

1. vena cava
2. pulmonary vein
3. aorta
4. pulmonary artery

Question 9

vena cava (right)

Answer 9

carries deoxygenated blood from the body to the heart

Question 10

pulmonary vein (left)

Answer 10

carries oxygenated blood from the lungs to the heart

Question 11

aorta (left)

Answer 11

carries oxygenated blood from the heart to the body

Question 12

pulmonary artery (right)

Answer 12

carries deoxygenated blood from the heart to lungs

Question 13

what is the purpose of valves?

Answer 13

prevent back-flow of blood

Question 14

what is the purpose of coronary arteries?

Answer 14

branch of aorta and supplying the heart with its own oxygenated blood

Question 15

process of blood flow through the blood

Answer 15

1) blood enters the right atrium (via vena cava) and left atrium (via pulmonary vein)

2) atria walls contracts, forcing blood into the ventricles. the valves to shut

3) the ventricles contract,
blood in the right ventricle - pulmonary vein (to lungs)
blood in the left ventricle - aorta (to body)

Question 16

what is the approximate value for resting heart rate?

Answer 16

70 beats per min

Question 17

what are pacemakers?

Answer 17

a group of cells controlling heart rate

Question 18

where are pacemakers found?

Answer 18

right atrium

Question 19

how do pacemakers work?

Answer 19

they provide electrical impulses which spread through muscle cells causing them to contract

Question 20

how can an abnormal heart rhythm be treated?

Answer 20

artificial pacemaker.
send our electrical signals to correct the heart rhythm.
implants - under the skin, wire connected to the heart

Question 21

what are the 3 types of blood vessels?

Answer 21

arteries
veins
capillaries

Question 22

how are arteries adapted for their function?

Answer 22

1) carry blood away from the heart
2) thick muscle layer - adds strength to resist high pressure of blood
3) thick elastic layer - allows arteries to stretch and recoil

Question 23

how are veins adapted for their function?

Answer 23

1) carry blood towards the heart
2) wide lumen - enables low pressure
3) valves - prevent back-flow of blood

Question 24

how are capillaries adapted for their function?

Answer 24

1) exchange nutrients and oxygen
2) walls are one cell thick - short path for diffusion
3) permeable walls - substances can diffuse across
4) narrow lumen - blood moves slowly - more time for diffusion

Question 25

rate of blood flow =

Answer 25

volume of blood / minutes

Question 26

what is the purpose of red blood cells in the blood?

Answer 26

transport oxygen around the body
(so cells can use it for cellular respiration)

Question 27

how are red blood cells adapted for their function?

Answer 27

1) biconcave shape - large surface area to absorb oxygen
2) no nucleus - more room for the “haemoglobin” to bind with oxygen
3) contains a red pigment “haemoglobin”

Question 28

what is the purpose of white blood cells?

Answer 28

defend us against pathogens

Question 29

how are white blood cells adapted for their function?

Answer 29

1) have a nucleus - contains DNA with protein codes
2) can produce antibodies, antitoxins
3) can engulf and digest pathogens (phagocytosis)

Question 30

what is the purpose for platelets in the blood? (are/do)

Answer 30

they are small cell fragments which clot blood at a wound

Question 31

why is the function of platelets important?

Answer 31

1) prevent microorganisms getting into the cut and infecting it
2) stop the bleeding

Question 32

what is the purpose of plasma?

Answer 32

carry different components of blood around the body

Question 33

what substances are transported by plasma?

Answer 33

red blood cells, white blood cells, platelets, carbon dioxide, urea, products of digestion

Question 34

what is plasma?

Answer 34

a yellow liquid within the blood that carries everything