S1) Homeostasis Flashcards Preview

(LUSUMA) Introduction to Cell Physiology and Pharmacology > S1) Homeostasis > Flashcards

Flashcards in S1) Homeostasis Deck (13)
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1
Q

The complex dynamic interaction of Matter, Energy and Fields in living cells is energy dependent.

Which 5 systems are required?

A
  • Substrate supply system
  • Product distribution system
  • Waste removal system
  • Stable controlled physicochemical environment (for reactions)
  • Control systems (monitor & adjust)
2
Q

Describe the mechanisms behind homeostatic control in terms of:

  • Control centre
  • Receptor
  • Effector
A
3
Q

What are the three types of signalling molecules?

A
  • Endogenous – Within the body

- Exogenous I – Natural

- Exogenous II – Synthetic

4
Q

Identify 5 examples of physicochemical parameters under homeostatic control

A
  • Temperature
  • pH
  • O2
  • CO2
  • H20
5
Q

In the following diagram, what function does the sensor have?

A

Sensor:

- Detects the physiological parameter

  • Produces a signal related to parameter
6
Q

In the following diagram, what function does the controller have?

A

Controller:

- Generates an amplified signal proportional to disturbance

  • Brings system output back towards set point
7
Q

In the following diagram, what function does the effector have?

A

Effector bring about change back to optimal set point

8
Q

Identify the two ways in which homeostasis can act and provide examples

A
  • Synergistically e.g. temperature – skin blood supply & sweating
  • -* Antagonistically e.g. insulin vs glucagon signal
9
Q

Why does there need to be precise temperature regulation in our bodies?

A
  • Most proteins operate optimally at 37°C
  • At higher temperatures, enzymes denature
  • Homeostasis reduce rate of thermal degradation of proteins
10
Q

Changes in thermal environment can be external and internal.

Provide an example of each.

A
  • Muscle use leads to large and rapid increases in temperature locally and throughout the body
  • Temperature of external environment can vary between +50oC to -40oC
11
Q

How does the body respond when body temperature exceeds 37oC?

A

Response = LOSE HEAT

  • Peripheral vessels dilate (heat radiates from skin surface)
  • Sweat glands activated (increasing evaporative cooling)
12
Q

How does the body respond when body temperature falls below 37oC?

A

Response = GAIN Heat

- Peripheral capillaries constrict (reducing heat loss from surface)

  • Skeletal muscle shivers (generating more heat)
13
Q

What affect does signal transmission route integrity have on homeostasis?

A
  • Transmission distance, velocity & time varies
  • If delayed, homeostasis performance and physiological function are affected