Respiration And Circulation In Tetrapods

Question 1

How does cutaneous respiration in Amphibians work?

Answer 1

It requires blood capillaries close to surface of exchange and increased surface area. Low keratinization of the skin is required for efficient gas exchange.

Water or moisture needed to maintain integument

Question 2

What is the general structure of tetrapods lungs?

Answer 2

• Paired, high surface area to volume ratio
• joined larynx and buccal activity by trachea
• trend toward increased compartmentalization

Question 3

Bird lungs ?

Answer 3

• aspiration pump
• air sacs and unidirectional air flow
• gas exchange in small capillaries

Question 4

What is two-cycle breathing?

Answer 4

Cycle one - air into posterior air sacs

Cycle two - air into anterior air sacs

Question 5

What is two-cycle breathing?

Answer 5

Cycle one - air into posterior air sacs

Cycle two - air into anterior air sacs

Question 6

How does gas transfer occur in Mammals, birds, and fish?

Answer 6

• Mammals - uniform pool
• Birds - cross-current exchange system
• Fish - counter-current system

Question 7

What system does tetrapod circulation require?

Answer 7

Double-circuit system

Question 8

What are the two types of circulation apart of the double-circuit system?

Answer 8

• systemic circulation = to/from body
• pulmonary circulation = to/from lungs

Question 9

How is amphibian double-circuit different from the traditional system?

Answer 9

• 3 chambered heart
• de-oxygenated blood enters from the body to the heart through the right atrium
• Oxygenated blood enters the left atrium from the lungs
• mixed oxygenated blood in the ventricle

Question 10

How does reptile double-circuit differ from the mammal system?

Answer 10

• 3 chambered heart
• de-oxygenated blood enters from the body to the heart through the right atrium
• Oxygenated blood enters the left atrium from the lungs
• ventricular cava allow transfer of deoxygenated blood to the lungs when breathing air and a lung bypass when diving

Question 11

How is the double-circuit pump pattern in (birds/mammals) differ?

Answer 11

• 4 chambered heart
• complete separation of pulmonary and systemic circulation
• de-oxygenated blood from the body entered the heart through right atrium
  -oxygenated blood from the lungs enters the heart at the left atrium

Question 12

What are the two bypasses in fetal circulation in mammals?

Answer 12

Bypass 1: right atrium blood exits through foramen

Bypass 2: blood from pulmonary artery travels through ductus arteriosus to lower body and placenta to be oxygenated