KA7- Absorption Of Materials

Question 1

Needed for respiration

Answer 1

Oxygen and nutrients from food must be absorbed into the bloodstream to be delivered to cells
Waste materials such as carbon dioxide (make blood dangerously acidic) must be removed from cells

Question 2

Which features increase the efficiency of absorption

Answer 2

Large surface area
Thin walls
Extensive blood supply

Question 3

Lungs

Answer 3

The organs responsible for gas exchange
Contain a large number of small alveoli which provides a large surface area where gas exchange takes place

Question 4

Alveoli

Answer 4

Tiny air sacs in the lungs where gas is exchanged during breathing
Lined with mucus and are surrounded by a network of blood capillaries
Layer of moisture allows the gas to be exchanged
Thin lining one cell thick allows rapid diffusion

Question 5

Individual air sac

Answer 5

Alveolus
Each surrounded by a network of capillaries which allows for quick transfer of oxygen into the blood and carbon dioxide out

Question 6

Mucus

Answer 6

Slimy white protein which lines the respiratory tract and alimentary canal

Question 7

Trachea

Answer 7

Wind pipe

Question 8

Direction of air

Answer 8

From the mouth and nose through the trachea to to the lungs which branches into two times called bronchi -one to each lung
Splits into smaller tubes called bronchioles which then end in microscope alveoli

Question 9

Diffusion direction

Answer 9

Oxygen diffuses from the alveoli into the blood
Carbon dioxide diffuses from the blood into the alveoli

Question 10

Small intestine

Answer 10

Well adapted for the rapid absorption of digested food because
-very long and folded
-internal surface area folded into finger like projections villi

Question 11

Villi

Answer 11

Finger like projections in the small intestine that provide a large surface area for the absorption of food

Question 12

Features of villus that aid absorption

Answer 12

Lining is only on cell thick - speeds up absorption
Capillaries in each villus to absorb glucose and amino acids
Lacteal to take up and transport the products of fats digestion (fatty acids and glycerol)

Question 13

Lacteal

Answer 13

Central vessel in the villi responsible for the absorption of fats

Question 14

Carbohydrate

Answer 14

Product of digestion - glucose
Absorbed in capillary

Question 15

Protein

Answer 15

Products of digestion - amino acids
Absorbed in capillary

Question 16

Fats (lipids)

Answer 16

Products of digestion- fatty acids and glycerol
Absorbed in Lacteal