LEC 1 A.P

Question 1

Slow wave are produced by

Answer 1

interstitial cell of cajal

Question 2

resting membrane potential of ICC/SM

Answer 2

depolarization and re-polarization from -65mV to -45mV.

Question 3

slow waveمصطلح

Answer 3

general name for spontaneous electrical rhythm)

Question 4

specific name of slow wave in GIT

Answer 4

Basalor Basic electrical rhythm (BER) or electrical control activity (ECA):

Question 5

Slow waves is not seen in

Answer 5

the esophagus and the proximal portion of the stomach

Question 6

Slow wave are not action potentials

Answer 6

spike potential→ A.P

Question 7

change in resting membrane potential OF ICC cause

Answer 7

undulating متموج and regular slow wave

Question 8

spike potential).

Answer 8

Slow wave when reach a threshold action potential appears

Question 9

The rate of the BER in stomach

Answer 9

4/min

Question 10

The rate of the BER in the duodenum

Answer 10

12/min

Question 11

The rate of the BER in the distal ileum

Answer 11

8/min

Question 12

The rate of the BER in the colon

Answer 12

2/min

Question 13

The rate of the BER in the sigmoid

Answer 13

6/min

Question 14

spike potential (true action potential) appears when

Answer 14

If the slow wave potential rise above (-40mV)

Question 15

The function of the BER is

Answer 15

to coordinate peristaltic and other motor activity

Question 16

contractions occur only during

Answer 16

the depolarizing part of the waves

Question 17

peristalsis in the stomach becomes irregular and chaoticفو

Answer 17

After vagotomy or transection of the stomach wall,

Question 18

سلايد 18

Answer 18

مراجعة

Question 19

The spike potentials spike lasting as long as

Answer 19

10 to 20 milliseconds.

Question 20

Slow wave without spike potential:

Depolarization

Answer 20

opening Fast Na channels

Question 21

Slow wave without spike potential

Repolarization:

Answer 21

opening of K channels

Question 22

Slow wave with spike potential

Depolarization:

Answer 22

opening Ca-Na channels,

Question 23

Slow wave with spike potential Repolarization

Answer 23

opening of K channels

Question 24

↑ potential

Answer 24

↑ contraction

Question 25

The spike potentials last 10 to 40 times as long in gastrointestinal muscle as the action
potentials in large nerve fibers

Answer 25

احفظيها مثل ما هي

Question 26

Innervation of smooth muscle cells.

Answer 26

1. Most through interstitial cells of Cajal.

2. Neurons can also directly innervate intestinal smooth muscle cells.

Question 27

↑ basal electrical rhythm of GI SM principle factor

Answer 27

1. stretch
2. acetylcholine
3. parasympathetic stimulation
4. some GI hormone

Question 28

↑ basal electrical rhythm of GI SM making them to be

Answer 28

1. more excitable

2. less (-) depolarization

Question 29

↑ basal electrical rhythm of GI SM factor causes

Answer 29

↑ the frequency of spikes

force of contraction

Question 30

↓ basal electrical rhythm of GI SM principle factor

Answer 30

1. sympathetic stimulation

2. epinephrine and epinephrine

Question 31

↓ basal electrical rhythm of GI SM making them to be

Answer 31

1. less excitable

2. more (-) hyperpolarization

Question 32

↓ basal electrical rhythm of GI SM factor causes

Answer 32

↓ the frequency of spikes

force of contraction

Question 33

Causes Smooth Muscle Contraction

Answer 33

spike potentials →calcium ions enter by L-type calcium channel and Na-Ca channels→ smooth muscle contraction

Question 34

slow waves do not cause muscle contraction why

Answer 34

slow waves do not cause calcium ions to enter the smooth muscle fiber (they only cause entry of sodium ions).