Transport in Animals

Question 1

Why do waste products like CO2 and urea need to be removed from the body?

Answer 1

To prevent them building up and becoming toxic.

Question 2

What are the three main factors that influence the need for a transport system?

Answer 2

Size
SA:V
Level of metabolic activity

Question 3

What two things does the body need to grow and survive?

Answer 3

Oxygen

Nutrients

Question 4

Explain briefly why very small animals do not have a need for a transport system.

Answer 4

All their cells are surrounded by or very close to the environment in which they live so diffusion can happen effectively enough to supply enough oven and nutrients to keep it alive.

Question 5

Increasing the diffusion distance (for example by adding more cells) will cause what?

Answer 5

Diffusion alone to be too slow to supply all of the organisms requirements.

Question 6

Define what transport is.

Answer 6

The movement of substances such as oxygen, nutrients, waste and air around the body.

Question 7

Small organisms have a ….. SA:V

Answer 7

Large

Question 8

Explain how the SA:V is affected the larger an organism gets and what affect this will have for the organism.

Answer 8

The larger the organism, the smaller the SA:V- the less able it is to supply all of its cells with oxygen and nutrients so there will be a higher need for a transport system.

Question 9

Explain the process in the body that requires oxygen.

Answer 9

Releasing energy from food by aerobic respiration.

Question 10

Explain how the level of metabolic activity of an organism will affect the need for a transport system.

Answer 10

The cells need more supplies of oxygen and nutrients the more active an organism is to supply the energy for movement.

Question 11

List the five things that an effective transport system will have.

Answer 11

• tubes or vessels to carry blood by mass flow
• two circuits- one to pick up O2 and other to deliver it to tissues
• exchange surfaces: let substances enter or leave blood (capillaries)
• pump to create pressure to push fluid around the body (heart)
• fluid or medium to carry nutrients, O2 and waste around the body (blood)

Question 12

Define what the single circulatory system is.

Answer 12

The blood flows once through the heart for each circulation of the body.

Question 13

In what organisms are single circulatory systems commonly found?

Answer 13

Fish

Question 14

Explain the route of the blood in the single circulatory system of fish

Answer 14

Heart
Gills
Body
Heart

Question 15

What are two disadvantages of the single circulatory system of fish?

Answer 15

It creates a low blood pressure so the blood is transported very slowly around the body and there is a limited rate of O2 and nutrient delivery and CO2 and urea removal.

Question 16

Explain what happens along the dishes single circulatory system for blood briefly.

Answer 16

The blood pressure drops as the blood passes through the tiny capillaries of the gills. Low BP as the blood flows towards the body very slowly. The rate at which O2 and nutrients is delivered to respiring tissues is limited, as well as the rate of CO2 and urea removal.

Question 17

Describe what the bounce circulatory system is.

Answer 17

One in which the blood flows through the heart twice for each circulation of the body.

Question 18

Explain how fish can get away with only having a single circulatory systems and animals can’t.

Answer 18

Fish aren’t as metabolically active as mammals as they don’t maintain their own body temperature- so they need less energy and the single system delivers enough oxygen and nutrients for their needs.

Question 19

What is pulmonary circulation?

Answer 19

In the DCS- the circuit that carried blood to the lungs to pick up oxygen.

Question 20

What is systematic circulation?

Answer 20

In the double CS- carries the oxygen and nutrients around the body to the tissues.

Question 21

What is the route of the blood in mammal’s double circulatory system?

Answer 21

Heart
Body
Heart
Lungs
Heart

Question 22

How can the blood be made to flow quicker around the body?

Answer 22

Additional pressure created by the heart.

Question 23

Compare the pressures that blood is carried at in pulmonary and circulatory circulation of the double circulatory system.

Answer 23

The systematic (oxygen and nutrients to tissues) circulation cartridge blood at higher pressure than the pulmonary (blood carried to lungs to be oxygenated) circulation.

Question 24

The increased pressure of the blood in systematic circulation means what?

Answer 24

The blood flows to the body quicker and more efficiently.

Question 25

Why must the blood be carried at a lower pressure in pulmonary (blood to lungs for oxygenation) circulation?

Answer 25

As it may damage the delicate one cell thick capillaries of the lungs of its carried at too high a pressure.

Question 26

Explain why there’s a need for a double circulatory system more in mammals than fish.

Answer 26

Mammals maintain their body temperature which requires respiration- more oxygen and nutrients are needed (and more waste removed) so the more efficient system is needed.