Blood Clotting

Question 1

What happens when you cut yourself?

Answer 1

Before long the blood thickens and the bleeding stops. The thickened blood has a formed a clot.

Question 2

Explain how clots can prevent disease.

Answer 2

Without clotting, blood would be lost and pathogens would get in.

Question 3

Explain how scabs form.(4)

Answer 3

1. ) The skin is cut and blood starts leaking out of the body.
2. ) There is a protein in the blood called fibrinogen. When the platelets come in contact with the air they turn the fibrinogen into threads of fibrin. The threads make a net over the cut.
3. ) Red blood cells get caught in the net and make a blood clot which seals the cut.
4. ) The clot dries to make a scab. New skin grows under the scab.

Question 4

What are platelets?

Answer 4

Fragments of cells.

Question 5

Where are platelets made?

Answer 5

In the bone marrow like the other blood cells.

Question 6

When a blood vessel is damaged the platelets start to work. They help to change fibrinogen to ______.

Answer 6

Fibrin

Question 7

What is fibrinogen?

Answer 7

It is a soluble protein found in the plasma.

Question 8

What do fibrin form?

Answer 8

Form a mesh work of threads. Red cells get trapped in the threads to make a clot.

Question 9

What is the job of the scab?

Answer 9

To keep the cut clean.

Question 10

what is haemophilia?

Answer 10

Sometimes a person cannot make a needed for clotting called Factor 8, the person’s blood may not clot easily and blood is lost.

Question 11

What are warfarin and heparin?

Answer 11

Drugs that thin blood preventing clots from forming in blood vessels. Clots can sometimes form in the case of deep vein thrombosis.

Question 12

Oxygen

Answer 12

• From the lungs to the rest of the body

- In the red cells

Question 13

Carbon dioxide

Answer 13

• From the body to the lungs

- In the plasma

Question 14

Dissolved food

Answer 14

• From the gut to the rest of the body

- In the plasma

Question 15

Urea

Answer 15

• From the liver to the kidneys

- In the plasma

Question 16

Hormones

Answer 16

• From the hormone glands to the rest of the body

- In the plasma

Question 17

Heat

Answer 17

• From the liver and muscles to the rest of the body

- In all parts of the blood

Question 18

Name 4 things about capillaries: (the smallest blood vessels)

Answer 18

• They have very thin walls
• They have a large surface area
• Body cells are never far from the capillary
• Blood flows through them very easily

Question 19

_______ leaks our through the capillary walls. It surrounds the _____. It is now called _______ fluid.

Answer 19

Plasma
Body
Tissue

Question 20

What does tissue fluid help with?

Answer 20

It helps substances to diffuse into and out of cells easily.

Question 21

_______ substances pass from the tissue fluid to the cells. ________ chemicals pass from the cells into the tissue fluid. Most of the tissue fluid then passes back into the blood capillaries.

Answer 21

Useful

Waste