Introduction to Medical Sciences & Homeostasis

Question 1

How is the human body organized?

Answer 1

In a complex society of cells, organized into tissues and organs.

Question 2

Define Homeostasis

Answer 2

The maintenance of a constant internal enviroment

Question 3

How is Homeostasis achieved?

Answer 3

Through the involvement of cooperative actions of organ systems, coordinated by the nervous system and endocrine system (hormones.

Question 4

Define Internal environment?

Answer 4

The ECF which surrounds all cells and is divided into plasma, the dynamic component contained within the blood, and the ISF.

Question 5

Where is ICF

Answer 5

Within the cell and occupies 60% of TBW also K is its major non penetrating solute.

Question 6

What’s the difference between ECF and ICF?

Answer 6

ICF majority of TBW 2/3 also K is higher in conc here

ECF 1/3 TBW also Na is higher conc here

Question 7

Explain the importance of maintaining the constancy of the internal environment?

Answer 7

To ensure the survival of cells

Question 8

Describe the principles behind negative feedback control

Answer 8

Any change in temperature etc are detected by receptors, which are fed to an integrating centre and compared to a reference level. If there is a difference, a signal is sent to an effector and the change is negated. The magnitude of the effector signal is proportional to the size of the response and the deviation.