Nokea
Which of the following is FALSE about the enteric nervous system?
- A. It works through local control.
- B. It consists of enteric sensory and motor neurons.
- C. Enteric interneurons connect sensory and motor neurons together.
- D. The enteric neurons are incapable of controlling digestive tract functions without the central nervous system (CNS).
Correct Answer: D
Rationale: Correct Answer: D
Rationale:
1. The enteric nervous system can autonomously regulate digestive functions locally without input from the central nervous system.
2. Enteric sensory and motor neurons are key components of the enteric nervous system, responsible for detecting stimuli and coordinating gut movements.
3. Enteric interneurons play a crucial role in connecting sensory and motor neurons within the enteric nervous system.
4. Choice D is false because the enteric neurons are capable of controlling digestive tract functions independently from the central nervous system.
You may also like to solve these questions
Which of the following vitamins is not stored in the liver?
- A. C
- B. D
- C. B12
- D. A
Correct Answer: A
Rationale: The correct answer is A: Vitamin C. Vitamin C is water-soluble and not stored in the liver. It gets absorbed in the intestines and any excess is excreted in the urine. Vitamin D (choice B) is fat-soluble and stored in the liver. Vitamin B12 (choice C) is also stored in the liver. Vitamin A (choice D) is fat-soluble and stored in the liver as well. Thus, the correct answer is A as it is the only water-soluble vitamin among the options.
The small intestine:
- A. Is shorter than the large intestine
- B. Its internal surface area is smaller than the large intestine
- C. It absorbs less water than the large intestine
- D. It contains bacteria as found in the large intestine
Correct Answer: B
Rationale: The correct answer is B because the small intestine has a larger internal surface area compared to the large intestine due to its extensive folding and villi. This increased surface area enhances nutrient absorption efficiency. Choice A is incorrect as the small intestine is longer than the large intestine. Choice C is incorrect as the small intestine absorbs more water than the large intestine. Choice D is incorrect as the small intestine typically does not contain the same amount of bacteria as the large intestine, which is known for its significant bacterial population.
It is true to say the following about the motility of the gastrointestinal system:
- A. It is regulated neurally but not by hormones
- B. Emptying of the stomach is mainly by segmentation contractions
- C. Movement of chyme along the small intestine is mainly by the migrating motor complex
- D. Peristalsis is seen in most parts of the GIT
Correct Answer: D
Rationale: The correct answer is D because peristalsis, a coordinated muscle contraction that propels food along the gastrointestinal tract, is indeed seen in most parts of the GIT. This process helps move food from the esophagus to the stomach, and then throughout the intestines for digestion and absorption. Peristalsis is essential for the proper functioning of the digestive system.
Choice A is incorrect because gastrointestinal motility is regulated by both neural and hormonal factors. Choice B is incorrect as the emptying of the stomach is mainly facilitated by the rhythmic contractions of the stomach muscles, not segmentation contractions. Choice C is incorrect as the movement of chyme along the small intestine is primarily due to segmentation and peristalsis, not the migrating motor complex.
Saliva is needed for:
- A. Digestion of sucrose
- B. Digestion of phospholipids
- C. Ability to speak
- D. Breaking food down into small pieces
Correct Answer: A
Rationale: Saliva contains an enzyme called amylase, which helps break down sucrose (a type of sugar) into glucose and fructose for digestion. Therefore, the correct answer is A. Saliva does not play a significant role in the digestion of phospholipids (B), speaking ability (C), or breaking food down into small pieces (D).
In the small intestine, movement of chyme is regulated primarily by
- A. secretin and cholecystokinin.
- B. the parasympathetic nervous system via the vagus nerve.
- C. local and mechanical stimulation.
- D. the enterogastric reflex caused by pressure of irritating substances in the colon.
Correct Answer: C
Rationale: The correct answer is C: local and mechanical stimulation. In the small intestine, movement of chyme is primarily regulated by local and mechanical stimulation, which triggers peristalsis and segmentation. This allows for the mixing and propulsion of chyme along the digestive tract.
A: Secretin and cholecystokinin are hormones involved in regulating pancreatic and gallbladder secretions, not movement of chyme in the small intestine.
B: The parasympathetic nervous system via the vagus nerve plays a role in stimulating digestive processes but is not the primary regulator of movement of chyme.
D: The enterogastric reflex is related to regulating stomach emptying in response to irritating substances, not movement of chyme in the small intestine.