Lecture 1

Question 1

Define physiology

Answer 1

1. the study of living things and how they function
2. understanding how the body works (from the smallest part (cells) to the whole body)
3. understanding how different parts of the body work together

Question 2

one word to describe homeostasis

Answer 2

constancy

Question 3

homeostasis

Answer 3

the maintenance of a relatively stable internal environment

Question 4

Negative feedback system

Answer 4

Negative feedback reduces the difference between the desired set point and the actual value. it works to reduce the initial stimulus and regain homeostasis

Question 5

Positive feedback system

Answer 5

positive feedback increases the difference between the normal set point and the actual value. It enhances the stimulation pushing the system away from homeostasis

Question 6

feedforward control

Answer 6

the initiation of a response in anticipation of a stimulus
(sight, smell, or thought of food can be enough to initiate salivation or digestion)

Question 7

Example of negative feedback loop

Answer 7

stimulus: decrease in temp
sensor: nerve endings
signal to integrating center: action potential
integrating center: hypothalamus
signal to effector to initiate response: action potential
effector: skeletal muscle
output: generation of heat

Question 8

Example of positive feedback loop

Answer 8

stimulus: baby head drops, pressure on the cervix
sensor: stretch receptors in the cervix
integrating center: brain —> release of oxytocin
effector: uterine smooth muscle
output: contraction

Question 9

Biological Hierarchy of organization

Answer 9

1. atom
2. molecule
3. cell
4. tissue
5. organ
6. organ system
7. organism

Question 10

Body fluid compartments

Answer 10

intracellular fluid (ICF)
- 2/3 of the total body water volume

extracellular fluid (ECF)
- 1/3 of the total body water fluid
consist of:
1. interstitial fluid
2. blood plasma