Human Homeostasis

Question 1

Each organ is an aggregate of many different cells held together by

Answer 1

intercellular supporting structures

Question 2

red blood cells, numbering 25 trillion in each

human being, transport what to where

Answer 2

oxygen from the lungs to the tissues

Question 3

About ? percent of the adult human body is fluid, mainly a water solution of ions and other substances.

Answer 3

60

Question 4

Although most of this fluid is inside the cells and is called ?, about one third is in the spaces outside the cells

Answer 4

intracellular fluid

Question 5

This extracellular fluid is in constant motion throughout the body. It is transported rapidly in the circulating blood and then mixed between the blood and the tissue fluids by ? through the capillary walls.

Answer 5

diffusion

Question 6

In the extracellular fluid are the ? and ? needed by the cells to maintain cell life.

Answer 6

ions and nutrients

Question 7

Cells are capable of living, growing, and performing their special functions as long as the proper concentrations of list five and other constituents are available in this internal environment

Answer 7

oxygen, glucose, different ions, amino acids, fatty substances,

Question 8

The extracellular fluid contains large amounts of what? plus nutrients for the cells, such as oxygen, glucose, fatty acids, and amino acids.

Answer 8

sodium, chloride, and bicarbonate ions

Question 9

It also contains ? that is being transported from the cells to the lungs to be excreted, plus other cellular waste products that are being transported to the kidneys for excretion.

Answer 9

carbon dioxide

Question 10

The intracellular fluid differs significantly from the extracellular fluid; specifically, it contains large amounts of what ? instead of the sodium and chloride ions found in the extracellular fluid.

Answer 10

potassium, magnesium, and phosphate ion

Question 11

The term homeostasis is used by physiologists to mean maintenance of nearly

Answer 11

constant conditions in the internal environment.

Question 12

Extracellular fluid is transported through all parts of the body in two stages. The first stage is movement of blood through the body in the blood vessels, and the second is movement of fluid between the ?

Answer 12

blood capillaries and the intercellular spaces between the tissue cells.

Question 13

As blood passes through the blood capillaries, continual exchange of extracellular fluid also occurs between the ? that fills the intercellular spaces.

Answer 13

plasma portion of the blood and theinterstitial fluid

Question 14

The walls of the capillaries are permeable to most molecules in the plasma of the blood, with the exception of

Answer 14

the large plasma protein molecules

Question 15

Therefore, large amounts of fluid and its dissolved constituents ? back and forth between the blood and the tissue spaces, as shown by the arrows.

Answer 15

diffuse

Question 16

This process of diffusion is caused by ? motion of the molecules in both the plasma and the interstitial fluid.

Answer 16

kinetic

Question 17

Thus, the extracellular fluid everywhere in the body—both that of the plasma and that of the interstitial fluid—is continually being mixed, thereby maintaining almost complete ? of the extracellular fluid throughout the body.

Answer 17

homogeneity

Question 18

Located in the body are ? major endocrine glands that secrete chemical substances called hormones

Answer 18

eight

Question 19

Note that the extracellular fluid contains a large amount of ? but only a small amount of ?

Answer 19

sodium potassium

Question 20

Also, the extracellular fluid contains a large amount of ?

ions, whereas the intracellular fluid contains very little

Answer 20

chloride