Lecture 1

Question 1

Normal blood pH?

Answer 1

Arteries 7.45
Veins 7.35
Overall 7.4

Question 2

Outside what blood pH range for a significant period of time is death likely?

Answer 2

Below 6.8 or above 8

Question 3

What is homeostasis?

Answer 3

The ability of an organism to maintain a constant internal and external environment despite intrinsic and extrinsic factors that may impinge on the system.

Question 4

What is negative feedback?

Answer 4

Results of an action inhibit further performance of that action e.g temperature control

Question 5

Feedback loop components and example

Answer 5

Variable- temperature
Sensor- nerve cells in skin
Control centre- hypothalamus
Effector- sweat glands in body

Question 6

Controlling high temperature?

Answer 6

Vasodilation
Sweating
Pilorelaxation
Stretching out

Question 7

Controlling being cold?

Answer 7

Vasoconstriction
Piloerection
Curling up
Shivering

Question 8

Positive and negative feedback examples?

Answer 8

Insulin for negative

Blood clotting for positive

Question 9

Core body temperature?

Answer 9

36.5 to 37.5

Question 10

Is a patient below 28 degrees with no vital signs dead?

Answer 10

No, not dead until warm and dead

Question 11

2 main organs for acid base balance?

Answer 11

Lungs- respiratory balance

Kidneys- metabolic balance

Question 12

What do kidneys do if blood acidotic?

Answer 12

Secrete h+ and retain hco3- (bicarbonate)

Question 13

Can you do the ph h+ calculation.

Answer 13

Yes or no

Question 14

What is normal H+ concentration at ph 7.4

What is it from 7.35 to 7.45

Answer 14

40 nmoles/L
36-44
Ph 7= 100
Change in ph of 0.3 gives a change in H+ concentration of a factor of 2

Question 15

Body ph buffer systems?

Answer 15

Phosphate icf
Protein icf and ecf
Carbonic acid and bicarbonat ecf

Question 16

Body water volumes?

Answer 16

70kg male
60% water
42L
One third extracellular 14L two thirds intracellular 28L
Blood plasma 25% 3L of which 40% is haematocrit
Interstitial 75% 11L

Question 17

Body water distribution for ages and body weights?

Answer 17

Infant highest water percentage
Then male
Then female

Obese and elderly lower water percentage

Question 18

What does increased ADH lead to?

Answer 18

Oliguria= less than 400-500 ml of urine produced in an adult daily

Question 19

What is osmolality?

Answer 19

Concentration of solution expressed as total number of solute particles per kg. Unlike osmolarity it does not depend on temperature and pressure

Question 20

What is the cause of increased serum osmolality but decreased urine osmolality?

Answer 20

Diabetes insipidous

Question 21

How does excess ADH affect serum and urine osmolality?

Answer 21

Decrease serum osmolality but increase urine osmolality.

Question 22

What is normal serum osmolality range?

Answer 22

280-300 moms/Kg

Question 23

What is oedema?

Answer 23

Fluid retention in the body

Question 24

What are fenestrations?

Answer 24

Holes in capillaries

Question 25

Cause of Oedema?

Answer 25

Liver failure- albumin not produced
Lymphatic system failure
Capillary damage e.g water in a blister
Over hydration of drinking too quickly- osmotic gradient and water into cells

Question 26

What is rigor?

Answer 26

Sudden feeling of cold accompanied by shivering, a rise in temperature and often sweating. Indicates the onset of fever.

Question 27

What is a febrile seizure.

Answer 27

Seizure in kids 6 months to 5 years old caused by an increased body temperature without any underlying conditions.

Question 28

What is the term for being over hydrated?

Answer 28

Hyponatremia