B3.3 Homeostasis

Question 0

How is urea made?

Answer 0

The break down of amino acids

Question 1

What’s homeostasis?

Answer 1

Maintaining a constant internal environment

Question 2

How is water lost?

Answer 2

Sweating
Urine
Breathing

Question 3

How are ions lost?

Answer 3

Sweating

Urine

Question 4

Why does water and ion level have to be controlled?

Answer 4

If it’s wrong water will move into or out of the cell by osmosis and damage the cell

Question 5

What temperature should the body be and why?

Answer 5

37

For enzymes to work properly

Question 6

What’s the thermoregulatory centre?

Answer 6

In the brain
Monitors and controls temperature
Has receptors sensitive to temperature

Question 7

What happens if your temperature is too high?

Answer 7

Wider capillaries
More blood near surface
Heat is lost
More sweat (which evaporates to cool you)

Question 8

What happens if your too cold?

Answer 8

Smaller capillaries
Less heat loss
Shiver which is a contraction of muscles which releases energy from respiration as heat

Question 9

What temperature is hypothermia?

Answer 9

35

Question 10

What hormones control sugar level?

Answer 10

Insulin

Glucagon

Question 11

What happens if there is too much sugar in the blood?

Answer 11

Insulin released
Liver converts glucose to glycogen for storage
So insulin allows glucose to move from the blood to body cells
Sugar levels drop

Question 12

What happens if there is too little sugar in the blood?

Answer 12

Glucagon released

Liver converts glycogen to glucose for respiration

Question 13

What’s diabetes?

Answer 13

Don’t produce insulin
Need injections
Test blood with blood usage testing strips

Question 14

What are the parts of the urinary system?

Answer 14

Kidney
Ureter
Bladder
Urethra

Question 15

What ultrafiltration?

Answer 15

In the bowmans capsule in the nephron
Filtering the blood
Gets rid of large molecules like cells or proteins

Question 16

What’s selective reabsorption?

Answer 16

Reabsorbing the sugar, ion and water needed (down an osmotic concentration gradient)

Question 17

What’s in urine?

Answer 17

Urea and excess water and ions

Question 18

Where do kidneys in kidney transplants come from?

Answer 18

Living related, living unrelated or cadaver donors ( brain dead)

Question 19

Why can it be hard to find a donor?

Answer 19

Long waiting lists
Tissue typing
Shortage of donors

Question 20

What’s kidney failure?

Answer 20

Where the kidneys don’t work properly

Question 21

Symptoms of kidney failure?

Answer 21

Confusion 
Fatigue 
Nausea
Blood in urine
Abnormal heart rhyme

Question 22

What’s dialysis?

Answer 22

A procedure where patients are connected to a machine which acts as a kidney for them

Question 23

How does dialysis work?

Answer 23

Blood is mixed with thinners to avoid clots them it’s removed and pumped opposite to the dialysis fluid so exchanges can occur

Question 24

What is dialysis fluid?

Answer 24

Similar levels of glucose so it doesn’t move
Similar levels of ions so it will only move if there isn’t enough ions in the blood
No urea so there’s a large concentration gradient so it diffuses from the blood

Question 25

How often do patients need to use a dialysis machine?

Answer 25

2-3 times a week for 4-6 hours

Question 26

Advantages and disadvantages of kidney transplants?

Answer 26

Cheaper for NHS, normal life after

Need immunosuppressant drugs, shortage of kidneys, it needs an operation, only lasts 8-9 years

Question 27

Advantages and disadvantages of kidney dialysis?

Answer 27

No storage or need for drugs

Expensive for NHS, regular sessions, have to change your diet

Question 28

How is a kidney transplant done?

Answer 28

Cut
Kidney in and old one out
Blood vessels attached 
Ureter connected to the bladder 
Closed up

Question 29

What is organ rejection?

Answer 29

If the antigens are different the body can create antibodies to kill the new organ

Question 30

How can they reduce organ rejection?

Answer 30

Tissue typing 
Immunosuppressant drugs (but then there's more chance of infection and they have to be taken for life)

Question 31

What’s a urinary tract infection and how is it treated?

Answer 31

A bacteria infection of the urinary system where protein is present in urine
Treated with antibiotics

Question 32

What’s renal failure and how is it treated?

Answer 32

Kidneys can’t filter the blood

Dialysis or transplant

Question 33

What does high blood pressure do?

Answer 33

It forces large molecules out of the blood into the filtrate
Can cause permanent damage