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Where does ADH act?

On the walls of the collecting duct/DCT

1

Where is glucose and water mostly reabsorbed into the blood?

PCT

2

What is the role of the LOH in the production of urine?

Role of LOH is to reduce the water potential in the medulla.
In the ALOH there is active transport of inks into the medulla.
The DLOH walls are permeable to water.
Water is removed from the DLOH by osmosis into the medulla.
The water potential of the tissue surrounding the collecting duct is lower than the fluid inside, so water is removed from the urine in the collecting duct.

3

Where are insulin molecules synthesised in a pancreatic cell?

Rough endoplasmic reticulum.

4

What is the role of ATP in a cell?

Releases 30kJ of energy for metabolism.
Phosphate is released by hydrolysis.
ADP joins pi during respiration or photosynthesis.
Energy is released in small quantities to prevent damage to cells.

5

How does the body respond to changes in external temperatures?

The peripheral thermoreceptors send impulses to the hypothalamus.
Bring about the changes after that.

6

Learn dat ornithine cycle boi.

Book

7

How do pregnancy sticks work?

They test for hCG (human chorionic gonadotrophin).
The hormone is small so can pass from the blood into the filtrate at the bowmans capsule.
Immobilised/monoclonal antibodies which are complementary to the hormone.
Antibodies attach to a dye which makes the line appear when the hormone binds.
Control blue line to use for comparison, 2 lines is preggers.

8

Describe glucagon.

Hormone that causes an increase in blood glucose.
Made in alpha cells in the islets of langerhans.

9

Describe glycogen.

Carbohydrate used for storage, produced in hepatocytes.

10

What is an auto immune condition?

A condition where the bodies own immune system attacks itself with antibodies.

11

Why Is damage to the myelin sheath harmful?

Less insulation.
Interferes with AP and stops Saltatory conduction.
Occurs in sensory neurones towards the brain towards the CNS.
Loss of feeling.

12

What is the name of the Hydrogen acceptor in anaerobic respiration?

Pyruvate and ethanal

13

What are the products of oxidative phosphorylation?

ATP H2O and NAD/FAD

14

What are the roles of coenzymes in the Calvin/Krebs cycles and oxidative phosphorylation?

NAD accepts H.
red NAD/FAD carries e- to the electron transport chain in ox phos. They also H+ for ox phos/chemiosmosis.
red NADP supplies H+ to calvin cycle.
Coenzyme A carries acetate to Krebs.

15

If the water potential of the plasm increases what effect does this have on blood cells?

The water potential outside of the blood cells is higher than inside.
Water enters the blood cells.
Blood cells might swell or burst.

16

Where is ADH produced?

Osmoreceptor/neurosecretory cells in the hyporthalamus.

17

Where do osmoreceptor cells detect the water potential of the blood?

In blood flowing through the hypothalamus.

18

How is ADH secreted into the blood?

Passes along the axon of neurosecretory cells to the posterior pituitary gland, it is then released into the blood.

19

Where does ADH act?

On the cell wall of collecting duct.

20

Where is ADH removed from the blood and what happens to the ADH molecule?

As protein:
In hepatocytes/liver.
Hydrolysed by protease.
Deamination forms NH3 + keto acid.
NH3 goes to the ornithine cycle to form urea, keto acid is used in kerbs cycle for respiration.

As small molecule:
In kidney.
Filtered from blood into the nephron because it's a small molecule.
ADH not reabsorbed so is excreted in urine.

21

What are the 1st/2nd messengers for adrenaline?

1st - adrenaline
2nd - cAMP

22

What does adrenaline cause a cell to do with glucose?

Glycogenolysis

23

What are the hormonal and nervous mechanisms that control the heart rate?

Adrenaline increases heart rate.
Cardiovascular centre in medulla oblongata.
Nervous connection to sino-atrial node controls waves of excitation.
Parasympathetic nervous system decreases the heart rate. Sympathetic increases.
High blood pressure is detected by stretch receptors.
Low blood pH is detected by chemoreceptors.

24

What are the differences between motor and sensory neurones?

Motor:
cell body in CNS
Cell body at the end of a neurone
Dendrites connect directly to the body Of the cell.
Longer axon.
No drondrons.

Sensory:
Cell body Not in CNS
Cell body in the middle of neurone
Dendrites at the end of axon
Shorter axon
Has dendrons

25

What Is a source of CO2?

Dry ice

26

Why is not all O2 released from plants?

Some used in oxidative phosphorylation.
Gets trapped in air spaces in the leaf.
Some may not be taken into measuring apparatus.

27

What does the basement membrane do?

Stops removal Of large molecules.

28

What do major processes do?

Ensures sure gaps to allow the passage of substrates.

29

Where are glucocorticoids produced?

Adrenal cortex