Lab 8: Bird

Question 1

On a downstroke what muscle is contracting?

Answer 1

Pectoralis major

Question 2

On a upstroke what muscle is contracting?

Answer 2

supracoracoideus

Question 3

How do birds breath?

Answer 3

Air sacs
First inhalations fills posterior sacs. Second exhalation goes from post sac to lungs. Second inhalation goes to anterior sacs and last exhaltions goes out.

Question 4

What are the advantages of having two circuits?

Answer 4

Blood can be pumped to the rest of the body at a higher pressure.

Lung to the heart is the pulmomary circulation
heart to other parts of the body/brain=systemic circulation

Question 5

What are the reasons for the physical differences between arteries and veins?

Answer 5

Ateries carry blood away from the heart oxygented-arteries have a thicker walls

Veins carry deoxygentated blood to the heart- thinning and use valves to keep blood flowing

Question 6

Why is the crop important?

Answer 6

The crop is the enlarged part of the esophagus
-for temporary food storage

Question 7

Why is the gizzard important?

Answer 7

fulfills the role og teeth