PHS 201 General Physiology & Body Fluids

Question 1

Who has a higher % of body water male or female and why?

Answer 1

Men 60%
Woman 55% because of more adipose fat tissues

Question 2

Who has a higher % of body water old/young and why?

Answer 2

Young, because adipose tissue increases with age, therefore water content decreases

Question 3

Significance of body fluids

Answer 3

In homeostasis: body cells survive in the fluid medium called internal environment, it consists of substances essential for growth and functioning of the cell. Water also plays a role in homeostasis.

In transport mechanism
In metabolic reactions
In texture of tissues
In temperature regulation

Question 4

How many L of water in a 70kg male

Answer 4

42L

Question 5

Intracellular fluid % and L
Extracellular fluid % and L

Answer 5

40% and 28L
20% and 14L

Question 6

Marker measure total body water

Answer 6

3H2O Tritium
2H2O Deuterium
Antipyrine

Question 7

Marker to measure extracellular fluid

Answer 7

Radioactive sodium
Chloride
Bromide
Sulphate
Thiosulphate

Question 8

Marker to measure plasma

Answer 8

Evans blue
Radioactive iodine (T-1824) : injecting serum albumin labeled with iodine
It can also be measure indirectly by measuring rbc volume

Question 9

Properties of an ideal marker

Answer 9

Non toxic
Not alter volume
Not be excreted
Easy to measure
Not be metabolized by the body during a period of time
Not change color of body fluid

Question 10

Where do gametes descend from?

Answer 10

Primordial germ cells in the walk of the yolk sac at 4th week of development

Question 11

Definition of physiology

Answer 11

Physiology is the study of processes and functions of living things

Question 12

definition of homeostasis

Answer 12

Homeostasis Is the Maintenance of Steady States in the Body by Coordinated Physiological Mechanisms.

Question 13

Who was the first to formulate the concept of the internal environment (milieu intérieur)

Answer 13

The nineteenth-century French physiologist Claude Bernard

Question 14

What was Claude Bernard’s ideology

Answer 14

He pointed out that an external environment surrounds multicellular organisms (air or water), but the cells live in a liquid internal environment (extracellular fluid)

Question 15

Who introduced the concept of homeostasis?

Answer 15

In the first half of the twentieth century, the American physiologist Walter B. Cannon

Question 16

what happens if blood glucose concentration is too low?

Answer 16

if blood glucose concentration is too low, the hormone glucagon, from alpha cells of the pancreas, and epinephrine, from the adrenal medulla, will increase it.

Question 17

what happens if blood glucose concentration is too high?

Answer 17

If blood glucose concentration is too high, insulin from the beta cells of the pancreas will lower it by enhancing the cellular uptake, storage, and metabolism of glucose.

Question 18

Disease or death is often the result of_

Answer 18

dysfunction of homeostatic mechanisms.

Question 19

cycle of self regulating devices (4)

Answer 19

1. Sensors or detectors, which recognize the deviation.
2. Transmission of this message to a control center.
3. Transmission of information from the control center to the effectors for correcting the deviation (either electrically through nerve impulses or .chemically through hormones in blood and body fluids)
4. Effectors, which correct the deviation

Question 20

What are feedback signals?

Answer 20

Feedback is a process in which some proportion of the output signal of a system is fed back to the input

Question 21

What is negative feedback?

Answer 21

Negative feedback is the one to which the system reacts in such a way as to reverse the direction of change

Question 22

What is positive feedback?

Answer 22

Positive feedback is the one to which the system reacts in such a way as to increase the intensity of the change in the same direction (a progressive change in one direction).

Question 23

What is adaptive control system and where is it typically seen?

Answer 23

Adaptive control system refers to a delayed type of negative feedback mechanism. This is seen in the nervous system

Question 24

resting membrane potential

Answer 24

The resting membrane potential of a neuron is the electrical potential across the neural membrane of an unstimulated nerve cell. It is around -70 mV

Question 25

action potential

Answer 25

An action potential is a rapid sequence of changes in the voltage across a membrane which is caused by depolarization

Question 26

Cycle of self regulating devices of a homeostatic system

Answer 26

1. Sensors or detectors, which recognize the deviation.
2. Transmission of this message to a control center.
3. Transmission of information from the control center to the effectors for correcting the deviation( transmission may be an electrical process = impulses through nerves or a chemical process = hormones through blood and body fluids).
4. Effectors, which correct the deviation.

Question 27

What is Feedback

Answer 27

Feedback is a process in which some proportion of the output signal of a system is fed (passed) back to the input to control the behavior pattern of the system

Question 28

What is negative feedback?

Answer 28

Negative feedback is the one to which the system reacts in such a way as to arrest the change or reverse the direction of change.

Question 29

What is positive feedback?

Answer 29

Positive feedback is the one to which the system reacts in such a way as to increase the intensity of the change in the same direction (a progressive change in one direction).

Question 30

Examples of negative feedback

Answer 30

Secretion of thyroxine
secretion of ADH

Question 31

Examples of positive feedback

Answer 31

1.Coagulation of blood
2.parturition
3.action potential
4.milk ejection reflex
5. follicular phase of menstrual cycle
6. calcium induced calcium release which occurs with each heartbeat

Question 32

What is Adaptive control system?

Answer 32

Adaptive control system refers to a delayed type of negative feedback mechanism. This is seen in the nervous system.

An adaptive control system detects the changes in the performance of the process and automatically regulates the controlling parameters

Question 33

What is hypovolemia?

Answer 33

A condition in which the liquid portion of the blood (plasma) is too low.

Question 34

Hoe does blood regulate acid-base balance?

Answer 34

Plasma proteins and hemoglobin act as buffers and help in the regulation of acid-base balance