Introduction

Question 1

Why do we need a cardiovascular system?

Answer 1

Metabolically active, use oxygen and produces carbon dioxide diffusion distance is too great

Question 2

Why does the heart need a blood supply?

Answer 2

The distance of the cells from the source of oxygen is too great so the muscle will become seriously damaged if the blood vessels are blocked

Question 3

What affects the area available for diffusion?

Answer 3

Area for exchange between capillaries, higher capillary density

Question 4

What does concentration gradient depend on?

Answer 4

The rate of use by the tissue, rate of blood flow in the capillary bed, lower the blood flow the lower the concentration gradient

Question 5

Blood flow normally

Answer 5

At rest total blood flow is 5 litres per minute

In exercise this can rise to 25 litres per minute

Question 6

What surrounds the heart?

Answer 6

The pericardial sac

Question 7

Layers of the pericardium

Answer 7

Fibrous layer

Outer serous layer the visceral and parietal layer

Question 8

The transverse pericardial sinus

Answer 8

The space behind the superior vena cava and the ascending aorta