Chapter 1: Functional Organization of the Human Body and Control of the “Internal Environment”

Question 1

This is the science that seeks to explain the physical and chemical mechanisms that are responsible for the origin, development, and progression of life

Answer 1

Physiology

Question 2

What is the basic living unit of the body

Answer 2

cell

Question 3

What is the most abundant of any single type of cell in the body?

Answer 3

red blood cells

Question 4

This refers to the communities of microorganisms that inhabit the body which can cause disease but most of the time live in harmony with their human hosts and provide vital functions that are essential for survival of their hosts.

Answer 4

Microbiota

Question 5

This refers to the internal environment of the body or the milieu intérieur, a term introduced by Claude Bernard in the 19th century

Answer 5

Extracellular fluid

Question 6

About how much percentage of the body (range) is fluid?

Answer 6

50-70% (mainly water solution of ions and other substances)

Question 7

What are the ions found in large amounts in the intracellular fluid?

Answer 7

Potassium, Magnesium, Phosphate ions

Question 8

Which ions are found in large amount in the extracellular fluid?

Answer 8

Sodium, Chloride, Bicarbonate ions

Question 9

This pertains to the maintenance of nearly constant conditions in the internal environment

Answer 9

Homeostasis

Question 10

What is the normal variation of blood hydrogen ion concentration?

Answer 10

5 nanomoles/L

Question 11

This term is considered to be a state of disrupted homeostasis

Answer 11

Disease

Question 12

This discipline of physiology seeks to explain how the various physiological processes are altered in disease or injury.

Answer 12

pathophysiology

Question 13

What are the 2 stages of extracellular fluid transport?

Answer 13

1: movement of blood through the body in blood vessels
2: movement of fluid between blood capillaries and the intercellular spaces between the tissue cells

Question 14

How may times in average do all the blood in the circulation traverse the entire circulatory circuit each minute when a person is extremely active?

Answer 14

6 times

Question 15

The capillary walls are permeable to most molecules in the blood plasma. Which molecules are too large to pass through capillaries readily?

Answer 15

plasma proteins

Question 16

What is the average thickness (range) of the alveolar membrane?

Answer 16

0.4 to 2.0 micrometers

Question 17

What is the major organ that changes the chemical compositions of many of the absorbed GI substances to more usable forms?

Answer 17

Liver

Question 18

This organ system provides motility for protection against adverse surroundings

Answer 18

Musculoskeletal system

Question 19

What is the most abundant of all the metabolism products of the body?

Answer 19

Carbon dioxide

Question 20

What are the 3 major parts of the Nervous system?

Answer 20

Sensory input portion
Central nervous system (integrative portion)
Motor output portion

Question 21

How much of the body’s weight (in percentage) is comprised by the skin?

Answer 21

12-15%

Question 22

The regulation of oxygen in tissues relies to a great extent on the chemical characteristics of which protein?

Answer 22

hemoglobin by its oxygen-buffering function

Question 23

This refers to the regulatory function of hemoglobin as to the oxygen concentration in the tissues

Answer 23

oxygen-buffering function

Question 24

The stretch receptors of the arterial walls are mainly found in which specific vascular location?

Answer 24

walls of the bifurcation region of the carotid arteries in the neck and in the arch of the aorta in the thorax

Question 25

What is expected to occur in the body if potassium ion concentration in the body decreases to less than one-third?

Answer 25

paralysis

**due to the inability of the nerves to carry signals

Question 26

What is the expected impact on the heart muscle if the potassium ion concentration increases to 2 or more times the normal?

Answer 26

severely depressed function due to hyperpolarization

Question 27

What is the expected outcome on the muscles if the calcium ion concentration decreases to half the normal?

Answer 27

tetanic muscle contraction due to spontaneous generation of impulses in peripheral nerves

Question 28

What determines the degree of effectiveness with which a control system maintains a constant condition

Answer 28

Gain of negative feedback

Question 29

The gain of the system is calculated by the formula:

Answer 29

Gain = Correction/Error

Question 30

This type of feedback is known as the viscous cycle

Answer 30

positive feedback

Question 31

This is the control system of managing homeostasis under dynamic conditions; the mechanism of the brain in which contraction is caused to control a rapid movement

Answer 31

Feed-forward control

Question 32

This is known as delayed negative feedback wherein the brain corrects the feed-forward signals to the muscles for subsequent movements.

Answer 32

Adaptive control