4.1 the blood

Question 1

What are the four main components of blood?

Answer 1

• plasma
• red blood cells
• white blood cells
• platelets

Question 2

What does plasma transport and where?

Answer 2

• blood cells
• waste carbon dioxide: to the lungs
• urea: to your kidneys
• soluble products of digestion: from small intesine to individual cells

Question 3

What is the function of red blood cells?

Answer 3

Pick up oxygen from the air in your lungs and carry it to the cells where it is needed

Question 4

What are the adaptations of red blood cells?

Answer 4

• Biconcave discs, to maximise the surface area to volume ratio for diffusion
• Haemoglobin that binds to oxygen
• No nucleus for more space for haemoglobin

Question 5

Is the reaction between oxygen and haemoglobin reversible?

Answer 5

Yes

Question 6

What is the function of white blood cells?

Answer 6

Fight against harmful microorganisms and can sometimes produce antibodies or antitoxins

Question 7

What do lymphocytes do?

Answer 7

Form antibodies against microorganisms

Question 8

What is plasma?/what it carries

Answer 8

It carries nutrients, co2, hormones, urea and blood cells around the body

Question 9

What are the adaptations of white blood cells?

Answer 9

• Form antitoxins
• Form antibodies
• Engulf bacteria

Question 10

Adaptations of plasma

Answer 10

Clear and watery to transport soluble molecules

Question 11

What are platelets

Answer 11

Small fragments of cells, that help the blood to clot

Question 12

What are the adaptations of platelets

Answer 12

-Small fragments that get trapped in protein fibres to produce a clot
- no nucleus

Question 13

Order red blood cells, plasma, white blood cells, platelets in order of amount in your body

Answer 13

Plasma
Red blood cells
Platelets and white blood cells

Question 14

How much blood does the average person have?

Answer 14

between 4.7 and 5 litres

Question 15

Why is urea formed and why does it go to the kidneys?

Answer 15

It is formed from the breakdown of excess amino acids and it is carried to the kidneys where it is removed from the blood to form urine

Question 16

Write the word equation for oxygen’s reaction with haemoglobin and where it takes place

Answer 16

(in the alveolus) haemoglobin + oxgyen —> (in the rbc) oxyhaemoglobin —> (in the body organ) —> oxygen + haemoglobin

Question 17

What do phagocytes do?

Answer 17

engulf and digest invading bacteria and viruses

Question 18

What is another function of wbc?

Answer 18

Form antitoxins against poisons made by microorganisms

Question 19

How does blood clotting work?

Answer 19

• It is a series of enzyme-controlled reactions that result in converting fibrinogen into fibrin
• This produces a network of protein fibres that capture lots of red blood cells and more platelets to form a jelly-like clot that stops you bleeding to death

Question 20

What happens to the wound after a jelly-like clot is formed?

Answer 20

• the clot dries and hardens to form a scab
• this protects the skin as it grows and stops bacteria from ending the body through the wound