Chapter 4B

Question 1

Why do fluids circulate in the body?

Answer 1

• To allow for the different organs and tissues in our
  body to function
  
  • Through the processing of pH, osmolarity, waste,
    nutrients, and gas exchange
• To allow for transportation of nutrients
• To allow for cullular components

Question 2

How does circulation occur in smaller organisms?

Answer 2

Diffusion is adequate in smaller organisms.

Question 3

Which organisms possess a circulatory system?

Answer 3

Organisms that are larger and multicellular.

Question 4

What do organisms with a high metabolic rate demand?

Answer 4

A fast circulatory system and this is because energy is being expelled at a fast rate so to replenish the O2 or nutrient supply the circulatory system must transport the material quickly.

Question 5

What is the cardiovascular system?

Answer 5

This system is a pump for nutrients and materials throughout the body where the heart acts as the pump for blood which is transported through the different vessels.

Question 6

What is the open circulatory system?

Answer 6

The blood is pumped through the vessels the nutrients are then emptied from the blood into the tissue and an open cavity and then returns to the circulatory system.

Question 7

What is the closed circulatory system?

Answer 7

Blood flows through the blood vessels by the heart pumping and then the blood flows through vessels to supply the tissues with nutrients.

Question 8

Is blood considered extracellular fluid?

Answer 8

Yes - since the blood is not contained within the cells.

Question 9

What are the components of blood?

Answer 9

1.) Plasma
2.) Erythrocytes
3.) Leukocytes
4.) Platelets

Question 10

How does the heart function?

Answer 10

The heart acts as a muscular pump the muscles in it contract and the blood flows from high to low pressure.

Question 11

What is the pressure of the blood as it approaches the heart?

Answer 11

Low

Question 12

What is the pressure of the blood as it leaves the heart and approaches the vessel?

Answer 12

High

Question 13

What are arteries?

Answer 13

These are vessels that carry blood away from the heart, control the blood distribution by the thickened walls, contract and expand to cause the heart beats, carry oxygenated blood with the exception of the pulmonary artery which carries deoxygenated blood to the lungs away from the heart.

Question 14

What are veins?

Answer 14

These are vessels that carry blood towards the heart, store the blood through the expansion of the vessel, carry deoxygenated blood with the exception of the pulmonary vein which carries oxygenated blood to the heart.

Question 15

What are the capillaries?

Answer 15

This is the exchange of substances between the blood and the tissues, and these are the thinnest vessels which promote diffusion and leake in some tissues.

Question 16

What is the circult for most fish?

Answer 16

A single circuit

Question 17

What is the circuit for most birds and mammals?

Answer 17

A double circuit

Question 18

What is the circuit for reptiles?

Answer 18

A variable circuit

Question 19

If a giraffe has hypertension to allow blood to reach its head how does it not faint everytime it raises its head?

Answer 19

Through the denseness in the connective tissues in its legs, its ebony knees that bend outwards, and the thick ventricles of the heart that do not stiffen, and pooling blood in its veins.