The Circulatory systems

Question 1

Why do certain organisms need transport systems?

Answer 1

in single-celled organisms & small multicellular organisms essential molecules can diffuse to where they’re needed due to the SA:V ratio and diffusion distance. Once an organism (e.g. early embryo) gets beyond a certain size it needs a transport system for more efficient distribution of essential molecules.

Question 2

What are some common features of transport systems?

Answer 2

.made up of tubes or vessels that carry materials from one part of an organism to another
.they make close contact with cells like the ones in exchange surfaces

Question 3

Describe the process of the heart pumping blood?

Answer 3

.check answer in notebook

Question 4

Double Circulatory System

Question 5

What are the benefits of having a double circulatory system?

Answer 5

.blood travelling thru small capillaries in the lungs loses a lot of pressure which reduces the speed at which it can flow so there’s more time for diffusion of gases at alveoli
.returns O2 blood to heart before pumping around body so pressure can be raised and the cells get O2 quicker

Question 6

Pulmonary Circulation

Answer 6

deoxygenated blood is transported to the lungs and back to the heart

Question 7

1

Answer 7

de-oxygenated blood is in the right atrium which contracts and pushes thru the valves (which prevent backflow) into the right ventricle

Question 8

2

Answer 8

Then the right ventricle contracts pushing blood up thru the (semi-lunar) valves, thru the pulmonary artery

Question 9

3

Answer 9

The pulmonary artery takes the blood to the lungs to undergo gaseous exchange

Question 10

4

Answer 10

The newly oxygenated blood then returns to the heart thru the pulmonary vein and enters the left atrium.

Question 11

What condition is pulmonary circulation under?Why?

Answer 11

Low pressure. Blood only has to be delivered to the lungs which are close to the heart and in a healthy person this low pressure is optimum for the diffusion of gases.

Question 12

Systemic Circulation

Answer 12

takes oxygenated blood around the body to cells that need it and transports waste materials away from the cells. and then returns to the heart when de-oxygenated

Question 13

A

Answer 13

The oxygenated blood is in the left atrium which contracts to push the blood thru the valves (which prevent back-flow) into the left ventricle

Question 14

B

Answer 14

Then the left ventricle contracts pushing the blood thru semi-lunar valves thru the aorta

Question 15

C

Answer 15

As the ventricle continue to contract, it pumps the oxygenated blood around the body and to the brain so it can provide O2 and take CO2

Question 16

D

Answer 16

Then, the now de-oxygenated blood returns to the heart through the 2 vena cavae into the right atrium

Question 17

What conditions is systemic circulation under?

Answer 17

.under high pressure coz it has to deliver blood to the extremities of the body