B2 Circulatory System - Blood (page 33)

Question 1

What is Blood?

Answer 1

Blood is a tissue. One of its jobs is to act as a huge transport system.

Question 2

What are the four main things in blood?

Answer 2

1) Red Blood Cells - they carry oxygen
2) White Blood Cells - defend against infection
3) Platelets - Help blood clot
4) Plasma - a liquid that carries everything in blood.

Question 3

What is the job of Red Blood Cells?

Answer 3

They carry oxygen from the lungs to all the cells in the body.

Question 4

What shape are Red Blood Cells, and why?

Answer 4

Their shape is a biconcave disc - (like a doughnut), this gives a large surface area for absorbing oxygen.

Question 5

Do Red blood cells have a nucleus and why?

Answer 5

No they dont. - this allows more room to carry oxygen.

Question 6

Red Blood Cells contain a red pigment, what is this called?

(pigment means the natural colouring)

Answer 6

Haemoglobin.

Question 7

In the lungs, haemoglobin binds to oxygen to become what?

Answer 7

oxyhaemoglobin.

Question 8

In body tissues, what happens to haemoglobin?

Answer 8

the reverse happens (regarding the lungs), oxyhaemoblobin splits up into heamoglobin and oxygen, to release oxygen to the cells.

Question 9

The more red blood cells you’ve got means what?

Answer 9

it means the more oxygen can get to your cell.

Question 10

At high altitudes, there is less oxygen in the air. How would this affect people who live at high altitudes?

Answer 10

People who live in high altitude areas, produce more red blood cells to compensate, due to lack of oxygen in the air.

Question 11

What is the job of White Blood Cells?

Answer 11

to defend against infection.

Question 12

How can White Blood Cells defend against infection?

Answer 12

1) Some can change shape to gobble up unwelcome microorganisms (bacteria/viruses) in a process called phagocytosis.

2) Others produce antibodies to fight off microorganisms, as well as antitoxins to neutralise any toxins produced by the microorganisms

Question 13

Do White Blood Cells have a nucleus?

Answer 13

yes.

Question 14

What are Platelets job?

Answer 14

They help blood clot at the wound - to stop all your blood pouring out, and to stop microorganisms getting in (so basically platelets just float about waiting for accidents to happen).

Question 15

What is Platelets?

Answer 15

they are small fragments of cells.

Question 16

Do Platelets have a nucleus?

Answer 16

No.

Question 17

What will happen if the body has a lack of platelets?

Answer 17

Lack of platelets can cause excessive bleeding and bruising.

Question 18

What is Plasma?

Answer 18

It is the liquid that carries everything in the blood.

Question 19

What colour is the plasma liquid?

Answer 19

It’s a pale straw-coloured (pale yellow) liquid that carries just about everything.

Question 20

Name everything that the plasma carries?

Answer 20

1 Red and white blood cells and
Platelets
2 Nutrients, like glucose and amino acids (these are the soluable products of digestion which are absorbed from the gut and taken to the cells of the body)
3 Carbon dioxide from the organs to the lungs
4 Urea from the liver to the kidneys
5 Hormones
6 Proteins
7 Antibodies and Antitoxins produced by the white blood cells.

Question 21

Blood tests can be used to diagnose loads of things not just disorders of the blood, why is this?

Answer 21

This is because the blood transports so many chemicals produced by so many organs, and it is easier to take a blood sample rather than I piece of muscle.

Question 22

Describe the purpose of platelets in the blood?

Answer 22

They help the blood to clot at the wound