2.5 the components of blood

Question 1

functions of the circulatory system:

Answer 1

1. oxygen: lungs - cells
2. carbon dioxide: cells - lungs
3. nutrients: intestines - cells
4. waste: cells - kidneys
5. keeping your body at the right temperature

Question 2

why is carbon dioxide carried to your lungs?

Answer 2

to be breathed out

Question 3

why is waste carried to your kidneys?

Answer 3

to be removed

Question 4

what happens to your blood after a little while?
(for example when the doctor takes a sample)

Answer 4

the blood naturally seperates into two large parts, with a small one in between

Question 5

what are platelets?

Answer 5

not really cells, but tiny fragments of cells

Question 6

so, if you put blood in a test tube and wait a little while - what will happen?

Answer 6

the blood will be divided:

• on the bottom - 45% red blood cells
• in the middle - >1% white blood cells and platelets
• on the top: 55% plasma

Question 7

what are the two min components of blood?

Answer 7

plasma 55%
blood cells 45%

Question 8

what’s plasma?

Answer 8

yellow liquid, mostly water
contains lots of dissolved parts:
- nutrients
- waste substances like carbon dioxide
- hormones
- oxygen

Question 9

what the parts of blood?

Answer 9

red blood cells
white blood cells
platelets and plasma

Question 10

where’s blood produced?

Answer 10

bone marrow of long bones (like femur)

Question 11

how are red blood cells shaped, and how are they different from all other body cells?

Answer 11

disc shapes, and are different because they lack a cell nucleus

Question 12

how does blood transport oxygen?

Answer 12

red blood cells contain a red substance called haemoglobin, which binds oxyegn

Question 13

why does our blood have a red color?

Answer 13

because there are a lot more red blood cells than white blood cells. red blood cells have haemoglobin which makes them red

Question 14

what is the color of blood when it is oxygenated, and what is it when it’s de-oxygenated?

Answer 14

oxygenated: bright red
de-oxygenated: deep red-purple

Question 15

do white blood cells have nuclei? what do they fight?

Answer 15

yes they do. the fight bacteria, viruses and other invaders (which may cause disease)

Question 16

how does your body react to invaders?

Answer 16

by making more white blood cells

Question 17

what are the 2 types of white blood cells?

Answer 17

phagocytes
lymphocytes

Question 18

what do phagocytes do?

Answer 18

change shape and stretch themselves to engulf and swallow bacteria, then digest the bacteria into small pieces that are no longer harmful

Question 19

what do lymphocytes do?

Answer 19

make substances called antibodies, espeicially produced to assist the phagocytes in destroying invaders such as bacteria.

Question 20

why do you get ill?

Answer 20

because it takes a while before your lymphocytes have made enough antibodies

Question 21

what happens each time a new invader gets into your body?

Answer 21

a new antibodie is produced, specific for the invader. they surround and stick to the invader so that the phagocytes can engulf them

Question 22

what will happen the next time the same invader enters your body?

Answer 22

the lymphocytes will remmeber how to make the specific antibodies much faster meaning your body is immune (to the invader). thus - you want get ill!

Question 23

are platelets involved in blood clotting? (for example when the skin is cut)why?

Answer 23

yes, becase it is important to prevent the entry of invaders through the open wound

Question 24

what can a clot prevent?

Answer 24

blood from flowing out of a punctured blood vessel for too long