Circulatory system

Question 1

What type of epithelial tissue is found in the Tunica intima?

Answer 1

Squamous epithelial tissue

Question 2

What type of blood vessel is found in the capillaires?

Answer 2

Tunica intima

Question 3

Backflow into the heart is prevented via valves. Which vessel does deoxygenated blood leave the heart through and which valve prevents its backflow?

Answer 3

Vessel –> pulmonary artery
valve–>semi-lunar

Question 4

Explain why Elastic arteries have elastic fiber (aorta)

Answer 4

The elastic fibers allow for expansion and for recoil of the aortic wall

Question 5

Distinguish between the Tunica media and Tunica externa.

Answer 5

Media-
smooth muscle
elastic fibers
heaviest wall layers are in the arteries
it contracts to maintain BP levels

Externa-
Collagen fibers
Heaviest wall layers in the veins
protects, reinforces and anchors vessels

Question 6

what is the difference between veins and arteries?

Answer 6

Veins have thinner walls than arteries
Their lumens are larger than the arteries
They have less elastic and smooth muscles compared to arteries

Question 7

Explain the functional adaptation of the Respiratory pump.

Answer 7

Pressure changes in the ventral cavity during breathing. As we inhale the abnormal pressure increases squeezing local veins at the same time the thoracic veins expands speeding blood flow to the RA

Question 8

Why do low BP requires adaptation?

Answer 8

To ensure that blood is returned to the heart at the same rate it was pumped into the circulation.

Question 9

How do the increased intercellular clefts play a role in the sinusoidal capillaries? Where are those capillaries found?

Answer 9

(i) They allow the large molecules to pass between the blood and surrounding tissue.
(ii) lymphoid tissue, liver, bone marrow, and some endocrine organs