Beginner Internal Anal Sphincter Quiz

Q1. What type of muscle forms the internal anal sphincter?

• Dense connective tissue
• Cardiac muscle
• Skeletal muscle
• Smooth muscle

Q2. The internal anal sphincter is a thickening of which muscle layer?

• Circular smooth muscle layer
• Superficial perineal muscle layer
• Muscular layer of the pelvic diaphragm
• Longitudinal skeletal muscle layer

Q3. Is the internal anal sphincter primarily under voluntary or involuntary control?

• Involuntary control
• No neural control
• Voluntary control only
• Conscious somatic control only

Q4. Which major function does the internal anal sphincter perform?

• Absorption of nutrients
• Maintenance of resting fecal continence
• Voluntary flexion of the hip
• Production of fecal material

Q5. Which anal sphincter is composed of skeletal muscle?

• Internal anal sphincter
• Rectal circular muscle
• Muscularis mucosae
• External anal sphincter

Q6. Which division of the nervous system primarily regulates the internal anal sphincter?

• Autonomic nervous system
• Brachial plexus
• Special sensory system
• Somatic motor system only

Q7. What is the usual resting state of the internal anal sphincter?

• Tonically contracted
• Voluntarily contracted only
• Completely relaxed
• Inactive until defecation

Q8. What generally happens to the internal anal sphincter when the rectum becomes distended with feces?

• It contracts maximally
• It detaches from the anal canal
• It relaxes reflexively
• It becomes skeletal muscle

Q9. Which muscle can be voluntarily contracted to help maintain continence when the internal anal sphincter relaxes?

• Detrusor
• Piriformis
• External anal sphincter
• Internal anal sphincter

Q10. The internal anal sphincter is located within the wall of which structure?

• Ureter
• Anal canal
• Sigmoid mesocolon
• Urethra