Lecture 1: Physiology Overview

Question 1

What is physiology?

Answer 1

The study of the normal functions/state of the body.

Question 2

To “get” physiology you have to think of the body on the level of

Answer 2

Cells; Cell biology

Question 3

About how many cells are in the human body, and what percentage of cells are Red Blood Cells versus everything else?

Answer 3

100 trillion; 25% RBC and 75% everything else

Question 4

What is homeostasis?

Answer 4

Maintaining a constant environment on the inside while keeping it separate from the outside.

Question 5

The “standard person” is ___ percent water

Answer 5

60%

Question 6

What are the two fluid compartments of the human body?

Answer 6

Extracellular fluid (ECF) and Intracellular fluid (ICF)

Question 7

Where is extracellular fluid located?

Answer 7

Outside of the cell

Question 8

What is extracellular fluid composed of?

Answer 8

150 mM Na+
5 mM K+
108 mM Cl-
pH 7.4

Question 9

What are the two subcompartments of extracellular fluid?

Answer 9

Blood and interstitial fluid.

Question 10

The fluid component of the blood is called

Answer 10

Plasma

Question 11

This surrounds all cells not in the blood

Answer 11

Interstitial fluid

Question 12

Where do the two subcompartments of the ECF, blood plasma and interstitial fluid, meet?

Answer 12

Capillaries

Question 13

Extracellular fluid makes up what fraction of the body’s water content?

Answer 13

1/3

Question 14

Where is intracellular fluid located?

Answer 14

Inside of the cell

Question 15

What is intracellular fluid composed of?

Answer 15

150 mM K+

5 mM Na+

Question 16

Intracellular fluid trades molecules with extracellular fluid via

Answer 16

Na+/K+ pumps or pores

Question 17

Intracellular fluid makes up what fraction of the body’s water content?

Answer 17

2/3

Question 18

What is the principal component of the cytosol/cytoplasm?

Answer 18

Intracellular fluid

Question 19

What are the two major types of control systems?

Answer 19

Positive and negative feedback.

Question 20

Which control system is more common?

Answer 20

Negative feedback

Question 21

What is negative feedback? Give an example

Answer 21

A change that drives a counterchange.
Example: Regulation of body temperature. When you are cold, your body shivers in order to generate heat. When you are hot, your body sweats to cool you down.

Question 22

What is positive feedback? Give an example

Answer 22

Positive feedback is a change that drives itself. It is when the product of a reaction leads to an increase in that reaction.
Example: Childbirth. Baby puts pressure on the cervix which causes contractions. Contractions lead to more pressure on the cervix. The cycle continues until the baby comes out.