Homeostasis And Physiological Control

Question 1

What is physiology?

Answer 1

The study of how organisms function and how function is controlled and maintained in order to keep us alive and healthy

Question 2

Physiological variable

Answer 2

Measure of a bodily function or bodily condition

Question 3

Homeostasis

Answer 3

Dynamic maintenance of physiological variables within a predictable range

Question 4

Negative feedback

Answer 4

The most common mechanism for the maintenance of physiological variables

Question 5

Set point

Answer 5

Normal value for a physiological variable

Question 6

Hypertension

Answer 6

High blood pressure

Question 7

Hypoxemia

Answer 7

Low oxygen levels in the blood

Question 8

Hyperglycemia

Answer 8

High blood glucose levels

Question 9

Osmolality

Answer 9

Salt/water balance

Question 10

Efferent pathway

Answer 10

Carries signals from integrating centre to effectors

Question 11

Afferent pathway

Answer 11

Carries signals from sensors to integrating centre

Question 12

Integrating centre

Answer 12

Compares inputs from sensors against physiological set point and elicit a response

Question 13

Three main types of negative feedback

Answer 13

Neuronal
Endocrine
Paracrine

Question 14

Negative feedback loop

Answer 14

Stimulus - change from normal set point
Sensors detect the change
Afférent pathway to integrating centre
Efferent pathway
Effectors to produce response

Question 15

Neuronal integrating centres

Answer 15

Mostly in midbrain or brain stem
Hypothalamus
Pons
Medulla

Question 16

What do neuronal integrating centres control?

Answer 16

Temperature
Osmolality
Blood pressure/flow control
Blood gas/breathing control

Question 17

Sympathetic vs parasympathetic nervous system

Answer 17

Sympathetic - noradrenaline
Parasympathetic - acetylcholine

Question 18

Human endocrine organs

Answer 18

Hypothalamus
Posterior pituitary
Anterior pituitary
Thyroid gland
Adrenal gland
Kidney
Pancreas
Testes
Ovaries

Question 19

Tyrosine derivative hormones

Answer 19

Thyroxine
Adrenaline

Question 20

Where is adrenaline produced?

Answer 20

In the adrenal medulla

Question 21

Classes of hormones

Answer 21

Protein hormones
Steroid hormones
Amine hormones

Question 22

Peptide hormone examples + where are they produced?

Answer 22

ADH
Oxytocin
Posterior pituitary

Question 23

Polypeptide examples + where are they produced?

Answer 23

Insulin (pancreas)
Growth hormone (anterior pituitary)

Question 24

Glycopeptides

Answer 24

Luteinising hormone
Follicle stimulating hormone
Thyroid stimulating hormone
Anterior pituitary gland

Question 25

Eg of steroid hormones

Answer 25

Estradiol
Cholesterol
Testosterone
Aldosterone
Cortisol

Question 26

What hormones are produced by the adrenal cortex?

Answer 26

Cortisol and aldosterone

Question 27

Paracrine homeostatic control

Answer 27

Negative feedback loop operates locally
Sensory, integrating centres and effectors are all located in the same tissue

Question 28

Feed forward

Answer 28

Anticipation of a change brings about the response to that change before the change can be detected by negative feedback sensors

Question 29

Positive feedback

Answer 29

A change in a variable triggers a response that causes further change in that variable
Amplification of a change