Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology > Membranes Biochemistry > Flashcards

Membranes Biochemistry Flashcards

1
Q

What is meningitis?

A

Infection of meninges of the brain

Usually due to vital/bacterial infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the meninges?

A

Membranes that cover brain neuronal tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are the meninges important?

A

Closely associated with blood brain barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the blood brain barrier?

A

Selectively permeable membrane that regulates passage of small + large molecules into microenvironment of neurons of brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are all the blood brain barriers?

A 
Blood-retina barrier
Blood-spinal cord barrier
Blood-cerebrospinal fluid barrier
Arachnoid barrier 
Blood-brain barrier
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What type of barrier is the blood-brain barrier?

A

Physical barrier to molecule penetration into brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is able to cross the BBB?

A

Pain killers (analgesics)
Anaesthetics
Antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What doesn’t cross the BBB?

A

Antihistamines
Chemotherapy drugs
Drugs that cause vomiting + nausea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the most important membrane?

A

GI tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is GI tract most important membrane?

A

Drug molecules need to be absorbed so they enter systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens when a patient takes a tablet?

A

Tablet enters stomach + dissolves
Absorbed in intestines
Enters circulation
Reaches action site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What must the drug be to be absorbed?

A

Drug must be in reasonable soluble form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens if a drug fails to be H2O soluble?

A

Cannot be absorbed from small intestine into systemic circulation
= therapeutic failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why may a drug be H2O insoluble?

A 
Tablet may not disintegrate (formulation problem)
Drug formulated in tablet granules = H2O insoluble
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What factors effect drug solubility of drugs?

A

Several polar groups - OH
Able to dissociate - eg. COOH
Poor electrolyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is having polar groups important for drug solubility?

A

Greater H bonding

= increases H2O solubility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why is being able to dissociate important for drug solubility?

A

Create proton + negative drug ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When are drugs poor electrolytes?

A

DO NOT dissociate readily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are examples of weak electrolytes?

A 
Acetic acid
Ammonium
Phosphoric acid
Carbonic acid
GOOD SOLUBILITY BUT POOR DISSOCIATION
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe small intestine

A

Villi
Supplied with blood
Receive lymph supply
Rudimentary nerve supply

21
Q

What is the gut wall structure?

A

Mucous coat
Submucous coat
Muscular coat
Serous coat

22
Q

Describe mucous coat

A

Surface epithelium with glands
Loose fibrous tissue with capillaries + lymphatic vessels
Muscularis mucosae
Lymphatic tissue

23
Q

What is villi linked to?

A

Epidermis

24
Q

What does epidermal cells have?

A

Small finger like protuberances

= increase SA for absorption

25
Q

What is structure of cell membrane?

A

Phospholipid bi-layer

26
Q

What is structure of phospholipid bi-layer?

A

H2O soluble polar head = outside

Fatty acid chain = inside

27
Q

What drug property factors affect absorption of drugs?

A

Lipid/H2O solubility
Molecular size
Degree of ionisation
Chemical structure

28
Q

How do drugs pass through cell membrane?

A

Passive diffusion

29
Q

What do drugs need to be to penetrate cell membrane?

A

Slightly hydrophilic to penetrate hydrophilic head

Slightly lipophilic to penetrate lipophilic head

30
Q

Why is paracetamol more likely to pass through cell membrane compared to Rifampicin?

A 
Paracetamol = small
Rifampicin = large
31
Q

What makes a drug more likely to pass through cell membrane?

A

Contain functional groups that donate or accept H+

32
Q

What does ionised form of a drug attract?

A

H2O = H2O soluble

33
Q

When is ionised form of a drug useful?

A

Enter hydrophilic area of membrane

34
Q

What happens when ionised form of a drug enters fatty acid section of membrane?

A

Ionisation reverses = drug becomes fat soluble

35
Q

What are the physical properties of membrane that affect drug absorption?

A

SA
Thickness
Conc gradient
^^^FICK’S LAW ^^^

36
Q

What happens in filtration?

A

Drug molecules pass through pore in membrane
Dissolved in bloodstream
Under increased pressure

37
Q

How does drug molecule pass through pore of membrane?

A

Force via dynamic pressure through pore

38
Q

What pressures are involved?

A

Hydrostatic

Osmotic

39
Q

What is the glomeruli?

A

Small sections of kidney

40
Q

What happens to blood vessels in kidney?

A

Blood supply under pressure
= blood vessels narrow
Increased blood pressure
= H2O soluble drugs forced out of blood vessels

41
Q

What happens to micro blood vessels in kidney?

A

Fluid forced out of micro blood vessels
THEN further forced through pores of membrane
Cells form Bowman’s capsule
Fluid collects + passes to bladder

42
Q

Why do anti-inflammatory pain killers have an effect upon kidney filtration?

A

Cause narrowing of blood vessels
= glomeruli vasoconstricts
= pressure + vol of blood to glomeruli reduced
= reduction in filtration

43
Q

Why is proportion of fluid reabsorbed by osmosis?

A

Blood vessels exert high osmotic pull

44
Q

Describe active transport across membrane

A 
Transported by pore or protein
Requires energy to open OR close pore
Against conc gradient
Energy from glucose + ATP
Pumps = move molecules against conc gradient
45
Q

What is endocytosis?

A

Process of cell ingesting material by enveloping it in proportion of cell membrane

46
Q

What is phagocytosis?

A

Endocytosis of large particles

47
Q

What is pinocytosis?

A

Brings fluid containing dissolved substances

48
Q

What is receptor-mediated endocytosis?

A

Endocytosis by portion of cell membrane that contains receptors specific to certain substance

Pharmacology (40 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions