Physiology of the Cell

Question 1

What is the approximate percentage of the body that is water?

Answer 1

60%

Question 2

What are the sources of body water in animals?

Answer 2

Food and water.

Question 3

What are the sources of water loss in animals?

Answer 3

Urination, defecation, respiration, evaporation & vocalization.

Question 4

What is the name of the state when an animal has too little water?

Answer 4

Dehydration.

Question 5

What is the name of the state when an animal has too much water?

Answer 5

Water intoxication.

Question 6

What are the names of the compartments in which water resides in the body?

Answer 6

Intracellular, extracellular which consists of interstitial fluid, plasma & lymph.

Question 7

Name 2 ways that abnormal fluid loss happens in animals.

Answer 7

Vomiting, diarrhea, blood loss, decreased intake of food or water.

Question 8

Describe the path of intravenous fluids after they have been administered.

Answer 8

Plasma​ to interstitial fluid​ to intracellular fluid to lymph.

Question 9

What is the body’s solvent.

Answer 9

Water

Question 10

Why are electrolytes so named?

Answer 10

They are capable of conducting an electrical charge.

Question 11

What 2 ions control the pH of body fluid?

Answer 11

The Hydroxyl and the Hydrogen ion.

Question 12

True or False. The common solutes in the body are all equally distributed in the intracellular & extracellular spaces?

Answer 12

False. Different solutes are distributed in different proportions in the different spaces.

Question 13

Maintenance of the osmolality of body fluid within the desired range is an example of what state?

Answer 13

Homeostasis.

Question 14

How would you describe 2 fluids with equal osmolality?

Answer 14

Isotonic.

Question 15

What direction will water flow in a situation where a cell is suspended in a fluid that is hypotonic to the contents of the cell?

Answer 15

Water will flow into the cell.

Question 16

Compared to that of a normally hydrated patient how is the osmolality of the plasma of a dehydrated patient?

Answer 16

The plasma will have higher osmolality in the dehydrated patient.

Question 17

What creates oncotic pressure?

Answer 17

Oncotic pressure is the osmotic pressure created by proteins as compared to dissolved substances.

Question 18

What is the name of the protein that creates oncotic forces?

Answer 18

Albumin.

Question 19

True or False. Water moves or doesn’t move between body compartments because channels in the barriers (membranes) between those compartments open and shut in response to signals from the body.

Answer 19

False. Water can move freely through membranes . Its “destination” is controlled by osmotic and oncotic forces.

Question 20

True or False Osmotic pressure is never sufficient to over come gravity?

Answer 20

False.

Question 21

What other force in the body is capable of moving fluid in the body and what generates this force?

Answer 21

Hydrostatic pressure. It is generated by the beating of the heart.

Question 22

Give 2 examples of transport of solutes across a cellular membrane that don’t require energy.

Answer 22

Diffusion & Facilitated diffusion

Question 23

Define diffusion. What obstacles are there to diffusion in the body?

Answer 23

Diffusion is the tendency of to spread out to be evenly distributed in the space available to them. Cell membranes and blood vessel epithelium are obstacles to this process.

Question 24

True or False. The movement of solutes by facilitated diffusion requires energy.

Answer 24

False

Question 25

List the 2 factors that affect the rate at which facilitated diffusion of a solute happens.

Answer 25

The concentration of the solute and the number of carrier proteins in the membrane available.

Question 26

What is the defining factor of active membrane transport.

Answer 26

It requires energy to get solutes across cell membranes.