Open And Closed Circulatory Systems

Question 1

What are the functions of a circulatory system?

Answer 1

1. Distribution of nutrients
2. Support for metabolism
3. Distribution of water and electrolytes
4. Transportation and distribution of hormones

Question 2

What are the principle components of circulatory systems ?

Answer 2

1. A fluid that circulates through the system
2. A propulsive mechanism that drives fluid flow by applying a force
3. A system of tubes or channels through which the fluid flows
4. A system of one-way valves or septa that ensure unidirectional flow of the fluid

Question 3

Features of an open circulation system

Answer 3

1. Incomplete system of vessels
2. Circulating fluid, known as haemolymph- it flows through vessels and freely percolates through intercellular spaces
3. Lower pressure, less efficient system

Question 4

Where is an open circulation system found?

Answer 4

Most mollusks, arthropods and some annelids

Question 5

Features of a closed circulation system

Answer 5

1. Fluid is enclosed within the system and does not contact cells directly
2. Fluid in vessels is blood, which is propelled by the heart
3. Higher pressure, so more efficient
4. Intercellular spaces filled with interstitial fluid

Question 6

Where is a closed circulation system found?

Answer 6

All vertebrates, cephalopod mollusks and some annelids

Question 7

What are the requirements of an efficient circulatory system?

Answer 7

1. Efficient O2 carrier in blood or haemolymph
2. Efficient gas exchange in the respiratory system
3. Fast flow of fluids

Question 8

What is the equation for flow rate ? When does movement occur ?

Answer 8

Flow rate = pressure gradient / resistance
Pressure gradient always has to be greater than R for movement to occur.

Question 9

What are the functions of the mammalian cardiovascular system?

Answer 9

1. Distribution of O2 and nutrients
2. Thermoregulation
3. Transportation of CO2
4. Immune system infrastructure