Transport in Animals

Question 1

Why are transport systems needed for single celled organisms?

Answer 1

To obtain nutrients and secrete waste by diffusion

Question 2

Why are transport systems needed for multicellular organisms?

Answer 2

• high metabolic demands
  -surface to volume ratio is small
  -high volume of substances needing transported by transporting molecules.

Question 3

What are the components of the circulatory system?

Answer 3

-Transport fluid
-Pumping mechanisms
-Vessels

Question 4

Where are open systems mostly found?

Answer 4

In invertebrates

Question 5

How is blood pumped through a open system in invertebrates?

Answer 5

Haemolymph is pumped (at low pressures) from the heart into the body cavity (haemocoel) where haemolymph is in direct contact to tissues. Returns to the heart by pores(ostia).

Question 6

What is a open system?

Answer 6

Tissue fluid is not contains in blood vessel but bathes in the tissue and cells.

Question 7

What are the advantages of a open system?

Answer 7

-Requires less energy for circulation
-well suited for organisms

Question 8

What are the disadvantageous of a closed system?

Answer 8

-Low blood pressure and moves slowly.
-Circulation can be affected by body movements.

Question 9

What is a closed system?

Answer 9

The blood is fully enclosed within blood vessels and does not come into contact with the cells.

Question 10

How is blood pumped through a closed system?

Answer 10

From the heart blood is pumped into a series of progressively smaller vessels then substances diffuse into cells. Then returns to the heart by larger vessels.

Question 11

Who normally has a double circulatory system?

Answer 11

Mammals, Birds, reptiles, amphibians.

Question 12

What happens in the double circulatory system?

Answer 12

One circuit takes the blood from the heart to the body then to the heart to the lungs then back.

Question 13

Why is it called the double circulatory system?

Answer 13

The blood travels twice through the heart for each circuit of the body.
It also passes through one capillary network- high blood pressure and fast flow of blood.

Question 14

Who normally has a single circulatory system?

Answer 14

Fishes

Question 15

What happens in the single circulatory system?

Answer 15

The blood is passed through two sets of capillaries after being pumped out of the heart which flows to the gills to be oxygenated.

Question 16

What does passing through 2 capillaries do?

Answer 16

The pressure is low and also lowers efficiency of blood returning to the heart quickly.

Question 17

What are the advantages of a single circulatory system?

Answer 17

Less complex. Does not require complex organs

Question 18

What are the disadvantages of a single circulatory system?

Answer 18

-low pressure
-Slow movement of blood
-Activity level of the animal tends to be low.

Question 19

What are the advantages of the double circulatory system?

Answer 19

-The heart can pump blood further around the body
-high pressure
-fast flow of blood.

Question 20

What are the different types of blood vessels?

Answer 20

Arteries
Arterioles
Veins
Venules
Capillaries

Question 21

What do blood vessels contain?

Answer 21

Elastic Fibres
smoot muscle
collagen

Question 22

What do elastic fibres do?

Answer 22

They stretch and recoil which helps vessels be flexible for withstanding high pressure.

Question 23

What do smooth muscle do?

Answer 23

It contracts and relaxes for changing the size of the lumen.

Question 24

What do collagen do?

Answer 24

Provides structural support to maintain shape and volume of vessel.

Question 25

Do arteries and arterioles carry deoxygenated blood or oxygenated blood?

Answer 25

Oxygenated blood( except from coronary artery)

Question 26

What is the job of the arteries?

Answer 26

To carry blood away from the heart.

Question 27

How does the structure of the artery help its job?

Answer 27

Narrow Lumen- helps with high pressure Thick elastic and muscle layer for expanding with heart beat and recoils( gives pulse)

Question 28

What is the job of arterioles ?

Answer 28

To link capillaries and arteries and constricts and dilates to move blood.

Question 29

How does the structure of the arterioles help its job?

Answer 29

Contains less elastin and more muscle tissue.

Question 30

Do veins and venules contain deoxygenated blood or oxygenated blood?

Answer 30

Deoxygenated except from the pulmonary vein.

Question 31

What is the job of veins?

Answer 31

To bring blood from the body to the heart.

Question 32

How does the structure of the veins help its job?

Answer 32

Lots of collagen and less muscle and elastin Has a wider lumen than others.

Question 33

What do Vein have that other blood vessels dont?

Answer 33

Valves made of the inner folding of the lining.

Question 34

What is the job of venules?

Answer 34

To link capillaries and veins

Question 35

How does the structure of the venules help its job?

Answer 35

No elastin fibres and no muscle fibres.

Question 36

What is the job of capillaries?

Answer 36

Links venules and arterioles to from a network.

Question 37

How does the structure of capillaries help with its job?

Answer 37

Made of only endothelium- one cell thick for a short diffusion pathway. -substances are exchanged through gaps in the endothelium

Question 38

What are adaptations for the cappillaries?

Answer 38

Large surface area-allows diffusion in and out. Small cross section- Reduces blood flow for more time for exchange of materials.

Question 39

What helps with blood flow?

Answer 39

Valves-prevents backflow Large veins- the muscles contract and pushes the blood through the vein Breathing movements- aids movement of blood.

Question 40

What are the functions of blood?(4)

Answer 40

-Transport -Defence -Thermoregulation -Maintaining pH of bodily fluids

Question 41

How large is a erythrocyte?

Answer 41

7 micrometres.