Circulation And Cancer Pt1

Question 1

What is the purpose of the circulatory system

Answer 1

To transport materials required by the cells (eg glucose and oxygen) and removed waste (eg carbon dioxide)

Question 2

What are the three parts of the circulatory system

Answer 2

The blood, the blood vessels, the heart

Question 3

What is the purpose of red blood cells

Answer 3

To carry the oxygen from the lungs to the respiring cells

Question 4

How are red blood cells adapted for their purpose

Answer 4

1. They are a biconcave disc shape, increasing surface area to volume ratio for oxygen to diffuse in and out
2. They do not have a nucleus allowing for more space for the carriage of oxygen

Question 5

What is haemoglobin

Answer 5

Haemoglobin is a protein in red blood cells that carries oxygen from the lungs to the rest of the body. Because it contains iron it can bind with oxygen in the lungs and release it in the tissues. It also helps transport carbon dioxide back to the lungs for us to exhale.

Question 6

Explain the colour of red blood cells

Answer 6

red due to the presence of hemoglobin, a protein that contains iron, when oxygen binds to hemoglobin in the lungs, it forms a bright red compound called oxyhemoglobin, which gives oxygenated blood its bright red color. In contrast, when red blood cells release oxygen to tissues, hemoglobin becomes deoxygenated, resulting in a darker red color in deoxygenated blood.

Question 7

Compare the size of white blood cells to reed blood cells

Answer 7

White blood cells are larger and less numerous than the red blood cells

Question 8

What is the function of white blood cells

Answer 8

They protect the body against infections by identifying and attacking pathogens such as bacteria and viruses

Question 9

What are platelets and their function

Answer 9

They are small fragments of cells without a nucleus that form a clot at the site of a wound by forming a mesh of protein fibres that trap other blood cells to form a scab preventing further blood loss and infection

Question 10

What is the purpose of blood vessels

Answer 10

Blood vessels carry blood away from the heart, as they experience pulses of high pressure they have thick muscular and elastic walls that can stretch. The lumen is relatively small to maintain the pressure

Question 11

What is the lumen

Answer 11

The hole down the middle

Question 12

What is the purpose of veins

Answer 12

Blood vessels that carry deoxygenated blood back to the heart at lower pressure and have valves to prevent black flow, their lumen are large, contractions of the skeletal muscles also help to keep the blood flowing back towards the heart.

Question 13

What is the purpose of capillaries

Answer 13

They are the only blood vessels that allow materials to enter or leave the blood, they form a huge network of narrow, thin walled vessels giving a large area for exchange, their lumen is narrow

Question 14

What circulatory system do humans have

Answer 14

Humans have a double circulatory system meaning that the blood flows through the heart twice during each full circuit

Question 15

What are the two circuits in a double circulatory system

Answer 15

Pulmonary circulation- carries deoxygenated blood from the heart to the lungs to be oxygenated
Systemic circulation- transports oxygenated blood from the heart to the rest of the body, afterwards the deoxygenated blood returns to the heart to complete the cycle

Question 16

What are the two circuits in s double circulatory system

Answer 16

Pulmonary circulation- carries deoxygenated blood from the heart to the lungs to be oxygenated
Systemic circulation- transports oxygenated blood from the heart to the rest of the body, afterwards the deoxygenated blood returns to the heart to complete the cycle

Question 17

Why is a double circulatory system efficient

Answer 17

Blood travelling to the body is fully oxygenated and can be pumped at high pressure to increase its speed of delivery

Question 18

What is the heart

Answer 18

The heart is a muscle that contracts in a coordinated sequence to move the blood around the body

Question 19

What is the job of the pacemaker cells

Answer 19

Pacemaker cells in the right atrium coordinate the muscle cells to contract together ensuring the heart beats in a consistent and efficient rhythm

Question 20

Describe the journey of blood throughout the circulatory system

Answer 20

1.Deoxygenated blood arrives through the veins from the body into the right atrium.
2.The right atrium contracts and forces the blood into the right ventricle.
3. The right ventricle contracts and forces blood up the pulmonary artery towards the lungs, valves stop the blood from moving back into the right atrium.
4.Oxygenated blood arrives through the pulmonary veins from the lungs into the left atrium.
5. The left atrium contracts and forces the blood into the left ventricle
6. The left ventricle contracts and forces the blood up the aorta to the body. Valves stop the blood from moving back into the left atrium
7.In reality contractions in the left and right hand occured simultaneously

Question 21

What is a stent and what is it used for

Answer 21

A stent is a etal mesh sleeve inserted into an artery and inflated with a balloon, they are used to wide blood vessels that supply the heart if they have been narrowed by fatty deposits

Question 22

What is a bypass surgery and what is it used for

Answer 22

It involves replacing narrow or blocked arteries with veins from another part of the body

Question 23

Anyone at risk of cardiovascular disease is likely to be prescribed ____ which lowers blood cholesterol and reduces fatty deposits in the artery walls

Answer 23

statin

Question 24

What are artificial heart valves and when are they used

Answer 24

Artificial heart valves are used if a persons natural heart valves begin to fail under the constant high pressure

Question 25

What are the pros and cons of mechanical valves of titanium and polymers

Answer 25

They will last forever
The patient needs to take drugs to prevent blood clots from forming

Question 26

What are the pros and cons of biological valves (from human donors or animals pigs or cows)

Answer 26

Do not require medication
Will only last for 15 years

Question 27

What are the pros and cons of biological valves (from human donors or animals pigs or cows)

Answer 27

Do not require medication
Will only last for 15 years

Question 28

What is an artificial heart and its function

Answer 28

They are mechanical devices that take over the job of a failing heart, they are primarily used as a temporary fix until a replacement human heart can be provided

Question 29

What is a natural pacemaker and what is it used for

Answer 29

An electrical pacemaker can be implanter in the chest, connected to the heart muscle that stimulates constant contractions if the natural pacemaker cells in the right atrium becomes damaged.

Question 30

What are communicable diseases

Answer 30

They are diseases that can be transferred from one person to another