Physiology Lecture 1: Principles and Homeostasis

Question 0

What are the unifying principle for physiology?

Answer 0

1. Evolution
2. Causal mechanisms
3. Structural and functional relationships
4. Homeostasis

Question 1

Define unifying principle

Answer 1

Theme can be used to explain a disciple of research, medicine, or science.

Question 2

What are unifying principles of osteopathic medicine (tenets)?

Answer 2

1. The body is a unit; the person is a unit of body, mind, and spirit
2. The body is capable of self-regulation, self-healing, and health maintenance
3. Structure and function are reciprocally interrelated
4. Rational treatment is based upon understanding of basic principles above

Question 3

What is homeostasis?

Answer 3

A dynamic process involving multiple mechanisms that work toward a steady state that is constantly in flux

Question 4

What are essential components to maintain homeostasis and their definitions?

Answer 4

1. Sensors: detect changes within the system
2. Afferent pathways: relay signal that change has occurred
3. Integration center: receives multiple inputs to dictate response
4. Effector pathways: relay signal to effectors
5. Effectors: mechanisms that alter original environment

Question 5

What are the types of feedback loops and examples for each?

Answer 5

1. Negative feedback - temperature regulation, blood glucose concentration
2. Positive feedback - childbirth and oxytocin, blood clotting

Question 6

Define set point and give examples

Answer 6

The functional range for a given variable - ie.

1. pH = 7.40 +/- 0.05
2. HCO3- = 24 +/- 2mEq/L
3. PCO2 = 40 +/- 5 mmHg

Question 7

Define steady state and give examples

Answer 7

Condition in which the variable is maintained, but only through constant adjustment
ie. blood glucose levels, intracellular Na+ concentrations

Question 8

Define equilibrium and give an example

Answer 8

Condition in which the variable is maintained without constant adjustment
Test-tube science

Question 9

Which of the following unifying principles could be used to explain muscular hypertrophy?

1. Evolution
2. Causal mechanisms
3. Form and function
4. Homeostasis
5. All of the above

Answer 9

5. All of the above

Question 10

Which of the following are considered causal mechanisms in muscular hypertrophy?

1. Exercise intensity
2. Exercise frequency
3. Diet
4. Steroids
5. All of the above

Answer 10

5. All of the above

Question 11

Which of the following is considered and functional and structural relationship in muscular hypertrophy?

1. Muscle mass to maximal force generated
2. Muscle mass to vascular supply
3. Muscle mass to bone density
4. Muscle mass to steroids
5. All of the above except 4

Answer 11

5. All of the above except 4 - muscle mass to steroids has minimal structure to function relationship

Question 12

Steroid use and attenuate endogenous testosterone production is an example of?

1. Negative feedback
2. Homeostasis
3. Causal mechanism
4. All of the above
5. Positive feedback

Answer 12

4. All of the above - excess exogenous steroid levels reduce endogenous production (negative feedback); reduce production to normal range (homeostasis); both of which are cause and effect mechanisms.

Question 13

Mechanistically, how does body position influence tidal volume?

Answer 13

Internal rotation of limbs decreases tidal volume, external rotation of limbs increases tidal volume.