Types Of Circulatory Systems

Question 1

What is an open circulatory system?

Answer 1

Where the blood is not always held within the blood vessels and circulates through the body cavity so cells are immersed directly in blood.

Question 2

E.g. open circulatory

Answer 2

In insects, the heart will pump blood towards head by peristalsis, enters heart through pores called ostia.
There is little control on direction of circulation and movement of muscles assist with movement of blood back to head.
There is no respiratory pigment, as insect blood does not carry O2
Blood is pumped at a low pressure in fluid filled cavity called haemocel

Question 3

What is a closed circulatory system?

Answer 3

Where blood is enclose within the blood vessels. The tissues are not in direct contact with blood and a Seperate fluid called tissue fluid exits capillaries and bathes the cells.
This allows the heart to pump blood at a higher pressure

Question 4

What are advantages of closed system?

Answer 4

1. Blood flow is more rapid and efficient
2. Blood flow can be directed to where it is needed by vascoconstriction and dilation e.g. more to working muscles/body surface if hot
3. More efficient delivery of o2 and nutrients (glucose) and removal of waste products like CO2

Question 5

What is a single circulatory system?

Answer 5

Where blood stays in a vessel on a single pathway around the body. The blood only passes through heart once before returning to gills (in fish).
In fish direction is heart -> gills -> body -> heart

Question 6

What is a double circulatory system?

Answer 6

Mammals are endothermic and produce own body heat so have high metabolic rate and high energy requirement. Their cells need large amount of O2 and nutrients and need to remove waste like CO2. So have double circ where heart pumps blood around body and twice through heart