CH:9 - Gas Exchange

Question 1

Gas Exchange Surface

Answer 1

Any part of an organism that allows the movement of gases between the surroundings and the body; gas exchange occurs across the body surface of some organisms that have large surface area : volume ratios;
Organisms with small ratios have specialised gas exchange surfaces, such as the lungs of mammals and the gills of fish.

Question 2

Alveolus

Answer 2

A small air sac in the lungs composed of a single layer of squamous epithelium and some elastic fibres; each alveolus is surrounded by capillaries that transport blood from the pulmonary artery to the pulmonary vein.

Question 3

Trachea

Answer 3

The tube-like structure that extends from the larynx to the bronchi; it allows movement of air into and out of the lungs.

Question 4

Bronchus

Answer 4

A major branch of the trachea that extends into the lungs.

Question 5

Bronchiole

Answer 5

A microscopic branch of a bronchus that leads to the alveoli.

Question 6

Cartilage

Answer 6

A type of skeletal tissue that is strong and flexible and supports the larynx, trachea and bronchi in the gas exchange system;
Cartilage is also found at joints between bones and in the external ear.

Question 7

Goblet Cell

Answer 7

A cell shaped like a drinking goblet that secretes mucus; goblet cells are found in epithelia lining parts of the gas exchange system and other organ systems, e.g. reproductive and digestive.

Question 8

Ciliated Epithelium

Answer 8

An epithelium that consists mainly of ciliated cells; may also contain goblet cells.

Question 9

Mucin

Answer 9

Any glycoprotein that forms part of the mucus secreted by goblet cells and mucous cells.

Question 10

Elastic Fibres

Answer 10

Bundles of the fibrous protein elastin which can stretch and recoil like elastic bands; they can stretch up to twice their length before breaking.