Chapter 2.6c The need for transport in animals: gas exchange and nutrient absorption

Question 1

Airways that link the atmosphere with gas exchange surfaces within the lungs are kept open with rings of

Answer 1

cartilage

Question 2

Most of the main airways are lined with sticky

Answer 2

mucus which traps dirt particles preventing these from reaching the gas exchange surface

Question 3

The mucus and trapped material in the airways are swept out of the lings by the movement of small hairs called

Answer 3

cilia

Question 4

The gas exchange surfaces are composed of thin-walled sacs called

Answer 4

alveoli

Question 5

Alveoli have a rich blood supply and form a

Answer 5

large surface area for efficient gas exchange

Question 6

Oxygen and carbon dioxide are exchanged by diffusion between the air and the blood through

Answer 6

the thin walls of the alveoli

Question 7

Swallowed food is moved through the digestive system by a muscular action called

Answer 7

peristalsis

Question 8

Digested food is absorbed through the small intestine wall and into the blood and

Answer 8

lymph

Question 9

The small intestine wall has thin walled folds called

Answer 9

villi which increase its surface area for absorption of digested food

Question 10

Each villus has a good blood supply and a central lymph vessel called a

Answer 10

lacteal

Question 11

Glucose and amino acids are absorbed directly into the bloodstream whereas the products of fat digestion pass into the

Answer 11

lacteals

Question 12

Lacteals lead into the

Answer 12

lymphatic system