Physiology and Pathology for Practice

Question 1

What is Physiology

Answer 1

science of life

understanding function

Question 2

Homeostasis

Answer 2

The maintenance of our internal environment to stay alive in hostile external environments

Question 3

Behavioural Responses

Answer 3

things we chose to do e.g. eating when we are hungry, holding your breath

Question 4

Physiological Responses

Answer 4

responses we have no control over e.g. increasing HR when we exercises, our body does this automatically

Question 5

Feedback loops

Answer 5

Body systems that are used to control a variable where there is a receptor, control centre and effectors

Question 6

Negative Feedback Loop

Answer 6

Where a change in a given direction causes change in the opposite direction
Help to maintain a constant setting
e.g. temp decreases so thermostat increases temp to desired set point

Question 7

Positive Feedback Loop

Answer 7

Where a change in a given direction causes additional change in the same direction
Accelerate a very specific response, stops once desired effect is over
e.g. ovulation

Question 8

Feedforward Loop

Answer 8

results in physiological responses in anticipation of a change in a variable
e.g. increased HR prior to a race

Question 9

Homeostasis in Physiology

Answer 9

Receptors detect changes in conditions and send this afferent information to brain control centres
Brain centres are collections of nerves that control physiological variables
They receive afferent info from the periphery then send efferent info to effector organs to negate or amplify the change.

Question 10

Tight control of homeostatic patterns

Answer 10

At any given time a variable will be very close to its predicted value e.g. pp02

Question 11

Loose control of homeostatic patterns

Answer 11

A variable may fluctuate in response to diurnal rhythms, mechanisms which ensure homeostasis occurs over a longer period of time. e.g. glucose regulation

Question 12

Gain

Answer 12

precision by which a control system can prevent deviation from homeostasis

Question 13

How to work out gain

Answer 13

amount of correction needed divided by amount of abnormality after correction

Question 14

Reflex Responses

Answer 14

Require knowledge from an integrating centre & a circuitry that connects receptors to effectors.

Question 15

Local Responses

Answer 15

individual body parts regulate their own homeostatic control

Question 16

Intercellular Communication

Answer 16

reflex - hormone directly acts on organ/ tissue

      - nerve cell acts through a transmitter to affecter cell
      - nerve cell stimulates a hormone to act on a target cell

local - local cell communicates with target cell (paracrine)
- local cell communicates with itself (autocrine)