Blood and Circulation

Question 0

Why do single celled organisms not need circulatory systems?

Answer 0

They can obtain oxygen through the surface membrane of the cell

Question 1

What are the three main types of blood vessels?

Answer 1

Veins, arteries and capillaries

Question 2

What do valves control?

Answer 2

The flow of blood to the heart

Question 3

What does blood clotting prevent?

Answer 3

The entering of pathogens and the prevention of excess blood loss

Question 4

Why do people need a transport system to carry sugar and oxygen to cells?

Answer 4

Humans have a very low surface area:volume area

Question 5

What is the process of double circulation?

Answer 5

The heart pumps blood to the lungs, getting back oxygenated blood which is sent to the heart to pump around the body

Question 6

What do valves do in veins?

Answer 6

Stop blood flowing in the wrong direction

Question 7

How are arteries adapted?

Answer 7

They have thick muscular walls to smooth out the pulses blood flow from the heart. Their walls must be able to stretch and they must be able to stretch and recoil.

Question 8

How are capillaries adapted?

Answer 8

They have very thin walls so that diffusion can occur more quickly. They bring the blood close to every cell in the organ. They must be small enough to fit between cells.

Question 9

How are veins adapted?

Answer 9

Large to carry blood to the heart Pressure is lower than in arteries, blood must be able to flow easily.

Question 10

What do arteries do?

Answer 10

Usually carry blood AWAY from the heart (except pulmonary artery)

Question 11

What do veins do?

Answer 11

Carry deoxygenated blood BACK to the heart (except pulmonary vein)

Question 12

Where does blood enter?

Answer 12

The atria of the heart

Question 13

What happens when the ventricles contract?

Answer 13

Blood leaves the heart and travels to the lungs and around the rest of the body

Question 14

How many heartbeats a minute (approx)

Answer 14

70

Question 15

What does your heartbeat increase after excercise

Answer 15

More oxygen is needed in the body

Question 16

Wat (lady) changes as the heart empties and fills?

Answer 16

The blood pressure

Question 17

What does the aorta do?

Answer 17

Carries oxygenated blood around the body

Question 18

What does the pulmonary vein do?

Answer 18

Brings oxygenated blood from the lungs

Question 19

What does the heart valves do?

Answer 19

Controls blood flow

Question 20

What does the pulmonary artery do?

Answer 20

Takes deoxygenated blood to the lungs

Question 21

What does the vena cava do?

Answer 21

Bring deoxygenated blood into the heart

Question 22

What is different about the heart in diagrams?

Answer 22

The left is shown on the right side

Question 23

What do red blood cells contain and for what purpose?

Answer 23

Haemoglobin to carry oxygen around the body

Question 24

What things does blood transport around the body?

Answer 24

Oxygen from the lungs to all other parts of the boys. Carbon dioxide from all parts of the body to the lungs. Nutrients from the gut to all parts of the body. Urea from the liver to the kidneys. Hormones, antibodies etc.

Question 25

What is the ratio of supply to demand in single called organism when obtaining oxygen?

Answer 25

Surface area / volume

Question 26

What is the difference between a single circulatory system and a double circulatory system? Name an animal that has a single circulatory system.

Answer 26

In a single circulatory system blood is pumped to the gas exchange organ and then straight to the rest of the body. In a double circulatory system blood is pumped to the gas exchange organ, back to the heart and then to the rest of the body. Fish.

Question 27

What are the names of the arteries/veins that connect with the liver?

Answer 27

Hepatic veins and arteries (Think hepatitis)

Question 28

What is the name of the veins and arteries that go to the kidneys?

Answer 28

Renal arteries and veins

Question 29

What is name of the vein that goes from the kidneys to the liver.l?

Answer 29

Hepatic portal vein.

Question 30

What is the systematic circulation?

Answer 30

When blood is circulated through all parts of the body where it unloads oxygen.

Question 31

Why is a double circulation system more effective than a single?

Answer 31

The heart pumps the blood twice so higher pressures can be maintained. The blood travels more quickly to organs. In the single circulatory system of a fish, blood loses pressure as it passes through the gills. It then travels relatively slowly to the other organs.

Question 32

What is the function of capillaries?

Answer 32

They carry the blood through organs.

Question 33

What side is the vena cava on?

Answer 33

YOUR right side DIAGRAM’s left side

Question 34

What side is the aorta on?

Answer 34

YOUR left side DIAGRAM’S right side

Question 35

What is the function of blood in a circulatory system?

Answer 35

It is the transport medium.

Question 36

What enables the heart to pump blood at different speeds and pressures?

Answer 36

The cardiac muscle. It is unlike any other muscle in our body and never gets fatigued.

Question 37

What is the cardiac cycle?

Answer 37

1. Blood enters the atria but cannot yet pass into the ventricles because the bicuspid and tricuspid valves are closed. 2.The walls of the atria contract which raises the blood pressure in them and opens the valves. Blood passes through the valves into the ventricles. 3. When the ventricles are full, they contract. This increases the pressure of the blood which closes the bicuspid and tricuspid valves again. Blood cannot return to the atria. 4. The ventricles continue to contract and the pressure continues to increase. This forces open the semi-lunar valves at the base of the aorta and the pulmonary artery. Blood is ejected into these two arteries. The aorta has branches to carry the blood to all other parts of the body. 5. As the ventricles empty, higher pressure in the aorta and pulmonary artery closes the valves in these blood vessels. The cycle begins again as the atria start to fill with blood.

Question 38

What is special about veins?

Answer 38

They have ‘watch-pocket’ valves which prevent the backflow of the blood.

Question 39

What is the purpose of ‘watch-pocket’ valves?

Answer 39

They prevent the back flow of blood. Especially important in veins when the deoxygenated blood must be pumped back to the heart.

Question 40

What are all the components in blood?

Answer 40

Plasma Red blood cells White blood cells Lymphocytes Phagocytes Platelets

Question 41

a) What is plasma? b) What is plasma’s function?

Answer 41

a) plasma is the liquid part of the blood, mainly water. b) plasma carries the blood cells around the body; carries dissolved nutrients, hormones, carbon dioxide and urea. Also distributes heat around the body.

Question 42

a) What are red blood cells? b) What are their function?

Answer 42

Bioconcave, disc-like cells with no nucleus; millions in each mm cubed of blood. They transport oxygen and contain mainly haemoglobin which loads oxygen in the lungs and unloads it in other regions of the body.

Question 43

a) What are lymphocytes? b) What are their function?

Answer 43

They are the same size as red blood cells with a large spherical nucleus. They produce antibodies to destroy microorganisms. Some lymphocytes persist in our blood after infection and give us immunity to certain diseases.

Question 44

a) What are phagocytes? b) What are their function?

Answer 44

They are much larger cells with a lobed nucleus, they engulf bacteria and other microorganisms that have been engulfed by our bodies.

Question 45

a) What are platelets? b) What are their function?

Answer 45

They are the smallest cells - actually fragments of other cells. They release chemicals to make blood clot.

Question 46

Where are red blood cells made?

Answer 46

Bone marrow.

Question 47

How do red blood cells load and unload oxygen?

Answer 47

Red blood cells contain haemoglobin, this combines with oxygen when there is a high concentration to become oxyhaemoglobin. This is when the red blood cell is loading oxygen. When the concentration of oxygen is low, oxyhaemoglobin turns back into haemoglobin and the red blood cell unloads its oxygen.

Question 48

How are red blood cells specially adapted for their function?

Answer 48

1. They have no nucleus, it is lost in their development in the bone marrow. This means that more haemoglobin can be packed into each red blood cell so mode oxygen can be transported. 2. Their bio concave shape allows efficient exchange of oxygen in and out of the cell as they have a high surface area to volume ration, giving a large aria for diffusion. 3. They have a very thin cell surface membrane meaning oxygen can diffuse through easily.