Phase One: Week Eight

Question 1

Explain the mechanism of GABA-A receptor

Answer 1

GABA is a main inhibitory neurotransmitter of the CNS. It binds to a ligand-gated chloride channel on the post-synaptic nerve cell. Chlorine will flow into the cell and cause hyperpolarisation and this inhibits action potential formation.

Question 2

What is Myasthenia Gravis?

Answer 2

This is muslce weakness. This is an autoimmune antibody attach of Ach receptor at the neuromuscular junction.

Question 3

What kind receptors do adrenaline and serotonin bind to?

Answer 3

G-protein coupled

Question 4

What are the three main G-alpha effectors?

Answer 4

Adenylyl cyclase, Phospholipase C and RhoGEFS

Question 5

What does adenylyl cyclase make?

Answer 5

cAMP

Question 6

What does phospholipase make?

Answer 6

IP3 and DAG

Question 7

Explain the process of protein kinase A activation

Answer 7

This is activated by cAMP. cAMP will bind to the two regulatory units of the PKA and this causes the catalytic subunits to become activated and dissociate.

Question 8

What is the affect of phospholipase C activation?

Answer 8

IP3 will be activated and this will cause calcium release into the endoplasmic reticulum. This will then activate calcium-depending kinases. DAG activates protien kinase C.

Question 9

Explain the process of adrenaline binding to a beta-one receptor

Answer 9

Adrenaline will bind and activate G-alpha and this will stimulate adenylyl cyclase. There will be an increase in cAMP. As beta-one receptors are located on heart muslce, their activation will cause increases heart rate and contraction.

Question 10

What is an example of selective beta-blockers (ones that only block beta-one)?

Answer 10

Atenolol

Question 11

Explain the process of adrenaline binding to a beta-two receptor

Answer 11

Adrenalin will bind and will activate G-alpha subunit. Adenylyl cyclase will be activated and this will increase cAMP. Due to their location being on the airway smooth muscle and vascualr smooth muscle, the effect is bronchodilation and vasodilation. This will cause increased blood supply to the muslce.

Question 12

What is sublingual administration?

Answer 12

Under the tongue

Question 13

What is topical administration?

Answer 13

Mucous membranes

Question 14

What is drug bioavailability?

Answer 14

The fraction of drug that reaches the systemic blood

Question 15

What is drug bioavailability?

Answer 15

This is the fraction of administered drug that reaches the systemic circulation.

Question 16

What is volume of distribution?

Answer 16

Fluid volume that would be required to contain the amount of drug present in the body at the same concentration as in the plasma

Question 17

What does volume of distribution depend on?

Answer 17

Plasma protein, tissue binding, molecular weight, lipid solubility

Question 18

What is loading dose?

Answer 18

This is an initial higher concentration given at the beginning of the course

Question 19

Name four efferent fibres that the Vagus nerve synapses with

Answer 19

The recurrent laryngeal, the Vagus, The phrenic and Spinomotor. The effector muscles include respiratory muscles, laryngeal muslces and bronchial smooth muscle

Question 20

What is the difference in the left and right recurrent laryngeal nerves in relation to the aortic arch?

Answer 20

The left goes in front of the aortic arch and the right goes behind.

Question 21

What is the difference in the epitheliums of the trachea and the oesophagus?

Answer 21

Trachea: Pseudostratified columnar epithelium
Oesophagus: Stratified squamous epithelium

Question 22

What are the four layers of the trachea?

Answer 22

The mucosa, basement membrane, submucosa and cartilage.

Question 23

Describe what happens during the first wave of public health

Answer 23

There is sanitary reform, municipal power, great public works and concern for social and civil order

Question 24

Describe what happens during the second wave of public health

Answer 24

There is a rise in scientific medicine, hospitals, health services and there is a rationalist approach

Question 25

Describe what happens during the third wave of public health

Answer 25

There is the welfare state, institutional reforms, NHS is establish, social housing, and there is a focus on living conditions. The politicians are key.

Question 26

Describe what happens during the fourth wave of public health

Answer 26

There is a focus on risk factors especially lifestyle and behaviours, There is emerging concern about inequalities.