Drug Absorption #2 Flashcards Preview

Pharmaceutics Spring 2016 > Drug Absorption #2 > Flashcards

Flashcards in Drug Absorption #2 Deck (94)
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1

T/F Passive diffusion is uni-directional

FALSE: can move in either direction (the concentration gradient determines which direction the molecule moves)

2

What are the 2 routes in which blood can diffuse?

intracellular(transcellular)
-paracellular

3

intracellular transport

molecules move directly through the membrane
-this is the most common

4

paracellular transport

molecules move between cells
-has a limiting factor (size of the molecules)

5

What is the limiting factor of paracellular transport?

the size of the molecule

6

T/F Carriers are typically proteins

TRUE

7

What are the 2 types of carrier mediated transport?

-facilitated
-active

8

Carrier Mediated Transport (2)

-are specific (only move one type of molecule)
-typically located in specific areas of the GI tract

9

T/F Carriers CAN NOT be saturated

FALSE; there are only a certain number of carriers, which means they can be saturated

10

T/F Carriers can be inhibited

TRUE

11

T/F Carrier transport is one direction

TRUE (mucosal side --> to the blood)

12

Which transport system requires ATP energy?why?

Active transport b/c it can occur from a region of lower concentration to higher concentration

13

metabolism

chemical altering of the drug molecule by the body

14

What is the effect of metabolites on bioavailability?

although metabolites are inactive--> they decrease bioavailbility because there would be a reduced amount of drug that would get to the site of action

15

efflux transporters (2)

-going in the opposite direction than what we would like
-typically P glycoproteins

16

P glycoproteins (3)

-energy driven
-pump the drug back in the direction in which it came from
-not as specific as carrier proteins

17

_____ are thought to cause tolerance to cancer therapeutic agents

P glycoproteins

18

What would be the effect of P glycoproteins on the bioavailability of the drug?

it would DECREASE the bioavailability because its taking the drug molecules in the opposite direction than we want them to go--> not allowing them to ultimately get to the site of action

19

What part of the stomach is where most secretion occurs?

the middle of the stomach

20

Antrum

holds material in the stomach to control how it moves to the pylorus

21

T/F The stomach is very muscular

TRUE

22

What are the functions of the stomach? (4)

-reservoir
-site of the beginning of digestion
-regulate the delivery of nutrients
-bacteriostatic

23

The secretion of ____ typically destroys the bacteria that make it to the stomach

HCl

24

What are the secretion cells in the stomach? (4)

-mucoid cells
-chief cells
-parietal cells
-g cells

25

mucoid cells

secrete mucus

26

mucus provides ____ and ____ protection

chemical and physical

27

chief cells

secrete pepsinogen (gets converted to pepsin)

28

____ begins the digestion process in the stomach

pepsin

29

parietal cells

secrete primarily HCl and intrinsic factors

30

intrinsic factors are necessary for...

absorption of B12