3. Cardiovascular System

Question 1

What are the 4 components of blood?

Answer 1

Blood plasma, red blood cells, white blood cells, platelets

Question 2

What is blood plasma?

Answer 2

• Blood plasma is a yellow liquid
• it carries all your blood cells and some other substances.
• they can carry waste carbon dioxide

Question 3

What are red blood cells?

Answer 3

• The most frequent cell in your body are red blood cells.
• they carry oxygen from your lungs to the rest of your body.
• red pigment from haemoglobin which binds to the oxygen

Question 4

What are white blood cells?

Answer 4

• less frequent but bigger than red blood cells.
• they form part of the bodies immune system and defence against harmful microorganisms
• some form antibodies and some form antitoxins.
• some engulf and digest the bacteria

Question 5

What are the platelets?

Answer 5

• Platelets are small fragments of cells.

- build up around a wound

Question 6

What are the features of arteries?

Answer 6

• Arteries carry blood away from the heart
• Thick walls because pressure is high
• thick layer of muscles and elastic fibres
• small lumen
• they stretch as blood flows through them.

Question 7

What are the features of veins?

Answer 7

• veins have a large lumen
• thin walls as there is lower pressure
• often have valves
• veins carry blood into the heart

Question 8

What are the features of capillaries?

Answer 8

• walls are single cell thick
• connect arteries to veins
• very narrow lumen

Question 9

If you have coronary heart disease, then what happens to your coronary arteries and why?

Answer 9

A build up of plaque from lipids build up in the coronary artery which is caused by damaged arteries.

Question 10

What effect does a build up of lipids in your artery have on your blood flow?

Answer 10

The build up of lipids causes the lumen of the artery to become narrower and therefor restricts the flow of blood. This leads to the artery becoming inflamed as it is the bodies response. This increases the chance of a heart attack.

Question 11

What is a stent?

Answer 11

A stent is a metal cage tube that can be opened. It is used to open the arteries when there is a build up of plaque. You put a small ballon inside the stent and push it to where there is a build up. You inflate the ballon which opens the stent and keeps it in that position and keeps the wall of the artery opened. You remove the ballon and the blood will be able to pass easily.

Question 12

What is a mechanical heart valve?

Answer 12

A mechanical heart valve is usually made from a lightweight, durable and strong material like titanium. They last about 20 to 30 years. Because of the material of the valve it is more likely that blood clots will form. This means the patient needs to take blood thinning drugs everyday for the rest of their lives.

Question 13

What is a biological valve?

Answer 13

A biological valve is usually an animals heart (most commonly pig). Lasts about 10 to 20 years. The risk of blood clotting is very low so no blood thinning drugs need to be taken. Biological valves are more expensive.

Question 14

What is a natural pacemaker?

Answer 14

The natural pacemaker is a group of cells in the right atrium which controls the bpm. The natural bpm is 70.

Question 15

What is an artificial pacemaker?

Answer 15

An artificial pacemaker is an electrical device implemented into the chest which corrects the beats your heart makes. It is attached to the heart with two wires.

Question 16

What is the passage of air through out body?

Answer 16

Nose, trachea, bronchi, bronchioles, alveoli, bronchioles, bronchi, trachea, nose.

Question 17

What surrounds the bronchioles?

Answer 17

A capillary network

Question 18

Why are the walls of the alveolus moist?

Answer 18

Makes it easier for the gasses to diffuse and prevent the inner surfaces from sticking.

Question 19

Explain the upper epidermis

Answer 19

• The upper epidermis is only once cell thick and is at the top of the leaf
• the cuticles is a waxy layer which protects the leaf from diseases such as fungi
• the cuticles is waterproof so that water isn’t lost by evaporation.

Question 20

Explain the palisade Mesophyll layer.

Answer 20

• Palisade cells have a spherical shape which helps light to penetrate the leaf
• the palisade cells contain the most chloroplasts than any other cell in the plant. Each one of these chloroplasts contains chlorophyll.
• the chloroplasts can move around the cells to where the light is the strongest.

Question 21

Explain the spongy mesophyll layer

Answer 21

• The spongy mesophyll layer contains irregularly shaped cells with large air spaces in between them
• this layer has less chloroplasts as less light reaches this layer.

Question 22

Explain the lower epidermis

Answer 22

• like the upper epidermis it is one cell thick.
• contains pores called stomata (stoma). Each stoma is made up of a pair of guard cells.
• the stomata allow gasses and water vapour to diffuse in and out of the leaf.

Question 23

Explain the leaf veins

Answer 23

• Water and salt enter the leaf through xylem cells.

- sugar made from photosynthesis is transported out of the leaf through the phloem.

Question 24

Explain the guard cells

Answer 24

The stomata open and close in response to changing light intensity, humidity, and carbon dioxide concentration.

Question 25

How is water transported through the plant in the transpiration system?

Answer 25

Long and stacked xylem vessels. They transport water and dissolved minerals.

Question 26

What transport the sugary sap in translocation?

Answer 26

Phloem vessels transport food substances made in the leaf to everywhere else in the plant.

Question 27

What 4 factors can affect the rate of transpiration?

Answer 27

Light
Temperature
Humidity
Wind Speed