Unit 2 - Key Area 7 - Absorption of Materials

Question 1

Which materials are absorbed and what happens to them?

Answer 1

Oxygen and glucose from food must be absorbed into the bloodstream to be delivered to cells for respiration.

Question 2

What are waste materials and what happens to them?

Answer 2

Waste materials such as carbon dioxide must be removed from cells into the bloodstream.

Question 3

Why do tissues contain capillary networks?

Answer 3

Tissues contain capillary networks to allow these exchanges to occur at a cellular level.

Question 4

What features do absorption surfaces have in common?

Answer 4

• A Large Surface Area
• Thin Walls
• Extensive Blood Supply

These increase the efficiency of absorption

Question 5

Describe how the lungs are efficient at gas exchange

Answer 5

1. The lungs have a large number of thin-walled alveoli (air sacs) providing a large surface area for gas exchange.
2. There are many thin-walled blood capillaries surrounding the alveoli to transport gases.

Question 6

Describe gas exchange in the alveoli

Answer 6

Oxygen moves by diffusion from a region of higher concentration (in the alveoli) to a region of lower concentration (in the blood capillary).

Carbon Dioxide moves by diffusion from a region of higher concentration (in the blood capillary) to a region of lower concentration (in the alveoli)

Question 7

What are the nutrients for the carbohydrates food group?

Answer 7

Glucose Molecules

Question 8

What are the nutrients for the fats food group?

Answer 8

Fatty Acids & Glycerol

Question 9

What are the nutrients for the proteins food group?

Answer 9

Amino Acids