Digestive System 1(Objectives)

General principles of Gastrointestinal Functions :

1. The alimentary tract provides the body with:

a) water and electrolytes

b) nutrients

c) enzymes

d) Both a & b

2. The GIT tract consists of the layers;serosa ,longitudinal muscle layer ,circular muscle layer, submucosa and ......................

3. The motor functions of gut are performed by ;

a) smooth muscle layer

b) circular muscle layer

c) serosa

d) both a&b

GIT SMOOTH MUSCLES FUNCTIONS:

4. An individual smooth muscle is ....................micrometer in length and .............................micrometer in diameter.

5. The peristalsis is regulated by two main types of muscles i.e.: .....................................................

6. The active potential of muscles is stored in the form of : .................................

Electrical activity of GIT smooth muscles:

7. The smooth muscle of the GIT is excited by continual electrical activity which is :

a) slow

b) fast

c) slow and intrinsic

d) fast and intrinsic

8. The motor activity of GIT is controlled mainly by :

a) neuronal control

b) change in resting membrane potential

c) hormonal secretions

d) both a&b

9. Most gastrointestinal contractions occur rhythmically and this rhythm is determined mainly by the frequency of the ................................. of smooth muscles .

10. slow waves are undulating changes in resting membrane potential and its intentisity varies b/w 5-15 .......................

11. It is assumed that the electrical pacemaker of the smooth muscle cells are ........................

12. The muscle contraction is excited by :

a) spike potential

b) slow waves

c) neuronal and hormonal stimulation

13. The true Action potential of smooth muscles of GIT is called as .................................

14. The important difference b/w Action potential of GIT smooth muscles and nerve fiber is ...................

15. The duration of action potential of smooth muscle fibers of GIT is .....................than that of neuron fibers . a) less

b) long

c) much more

d) much less

16. When resting membrane potential becomes more negative ,the smooth muscle fibers of GIT become more .................

17. Acetylcholine causes the smooth muscles to be ..........................

a) polarized ,

b) depolarized ,

c) make more excitable

d) make less excitable

18. Parasympathetic nerve stimulation causes the ................................... of the smooth muscles of GIT .

19. Epinephrine & nor-epinephrine cause the ...................................of the smooth muscles of GIT .

Answers to Objective Type Questions of Digestive System:

1. d


2. mucosa

3. a

4. 200 to 500 and 2 to 10

5. longitudinal and circular

6. Na & Cl ions

7. c

8. b

9. Slow waves.

10. Milli volts

11. interstitial cells .

12. a

13. spike potential

14. manner of generation

15. b

16. excitable

17. b

18. excitable

19. hyper polarization/ less excitation

Further Reading:
Textbook of Medical Physiology: With STUDENT CONSULT Online Access

Guyton and Hall Physiology Review

Pocket Companion to Guyton & Hall Textbook of Medical Physiology

Tag:
Preparation of Pharmacy Exams, Tests of Physiology, MCQs of Physiology