CH 1: Intro to Human Physiology

Question 1

Oxygen

Answer 1

65%
- element most abundant by MASS w/in human body

Question 2

Hydrogen

Answer 2

63%
- element most abundant by NUMBER w/in human body

Question 3

Teology

Answer 3

In philosophy, the science/doctrine that attempts to explain the universe in terms of ends or final courses

Question 4

Mechanistic

Answer 4

Explains the phenomena of nature on the principles of physical processes
*often seq. of events

Question 5

Physiology

Answer 5

Study of mechanisms by which living organisms function
“Knowledge of nature”

Question 6

Organization of the body

Answer 6

cells–>tissues–> organs–>systems–>whole body

Question 7

Organ

Answer 7

two or more types of tissues

Question 8

Fluid compartments

Answer 8

ICF & ECF

Question 9

Intracellular fluid (ICF)

Answer 9

• inside cells

Question 10

Extracellular fluid (ECF)

Answer 10

• is located outside cells but still inside body
• internal environment of the body
• interstitial fluid
• blood plasma

Question 11

Material moving b/t cells & ECF must cross what?

Answer 11

The cell membrane

Question 12

Cells gets their oxygen & nutrients from what?

Answer 12

The ECF

Question 13

Homeostasis

Answer 13

Maintenance of a relatively stable internal environment
*Body temp increases/decreases, not fixed

Question 14

Homeostasis maintains?

Answer 14

(Good)
1. Concentration of nutrients
2. Con. of gases
(Bad)
3. Con. of wastes
4. Con. of water & salt
5. pH
6. Temp.

Question 15

Metabolism (breaking down molecules)

Answer 15

Is an input of heat

Question 16

Mass balance

Answer 16

input = output

Question 17

Control pathways strive to maintain near constant set point…

Answer 17

• normal deviation occurs around the set loop
• body sets up mechanism in attempt to stay w/in range

Question 18

Heat stroke

Answer 18

Water is protected by body (hierarchy), so body temp increases and body “cooks”
- brain cooks
- proteins denature

Question 19

Stability

Answer 19

Balance b/t inputs & outputs

Question 20

Complete constancy is not maintained…

Answer 20

Only a narrow range of physiological values
- don’t mind variables changing, but can’t be too far

Question 21

In negative-feedback system, changes move the variable back toward what?

Answer 21

Initial set point

Question 22

Set points can be physiologically reset by being what?

Answer 22

Raised or lowered

Question 23

Why are variables ranked in a hierarchy?

Answer 23

Because not everything can be homeostatically maintained

Question 24

Inability to maintain homeostasis leads to what?

Answer 24

A pathological condition
- pathophysiology
*Departure from nature

Question 25

Pathophysiology

Answer 25

Study of disease condition

Question 26

Homeostasis: 2 types of responses

Answer 26

1. Local control
2. Feedback (response) loops

Question 27

Local control

Answer 27

• isolated changes occur w/in a tissue
• stimulus & control occur w/in same area
• a response loop is not utilized
  ex: crush finger w/ door

Question 28

Feedback (response) loops

Answer 28

*2 types: neg. & pos. feedback loop
- long-distance communication & coordination
- stimulus & response are not necessarily together (may not be in same tissue)
- includes nervous/endocrine system

Question 29

Negative feedback loop

Answer 29

Regulatory mechanism in which a change in a controlled variable triggers a response that tries to oppose the change
- a stimulus is detected by sensors in the body…an effector (organ of response) carries out a response that reverses the trend of the stimulus, so it can try to maintain the characteristics of the ECF

Question 30

Positive feedback loop

Answer 30

Regulatory mechanism in which a change in a controlled variable will trigger a response that drives us further & further from the setpoint
- creates more stimulus
- doesn’t maintain homeostasis
- body will not generally use it…

Question 31

Physiological control systems keep regulated variables w/in a what?

Answer 31

A desired range (set-point) during homeostasis