3.3 Gas exchange

Question 1

Intercostal muscles can be described as ….?

Answer 1

An antagonistic pair

Question 2

What is an antagonistic pair ?

Answer 2

As one thing contacts the other relaxes

Question 3

Contraction of the external intercostal muscles leads to ….?

Answer 3

Inspiration

Question 4

Contraction of the internal intercostal muscles leads to ….?

Answer 4

Expiration

Question 5

What is pulmonary ventilation ?

Answer 5

The total volume of air that is moved into the lungs during one minute

Question 6

How do you calculate pulmonary ventilation ?

Answer 6

Tidal volume x Ventilation rate

Question 7

What are spiracles ?

Answer 7

They are round, valve like openings running along the length of the abdomen.

Question 8

What is the trachea ?

Answer 8

A network of internal tubes that branch into smaller tubes deeper into the abdomen of the insect called tracheoles.

Question 9

What are 3 adaptations for efficient gas exchange in insects ?

Answer 9

• Large number of fine tracheoles to give an increased surface area
• Short distance between trachea and spiracles gives a short diffusion pathway
• Steep diffusion gradients between CO2 and O2

Question 10

What are 3 adaptations for preventing water loss in insects ?

Answer 10

• Waterproof exoskeleton
• Spiracles
• Small SA:V