Biology · Science General

Human Digestive System

2,002 Questions

The human digestive system explores the breakdown of biomacromolecules, covering organs from the stomach to the small intestine. It involves physiological processes like chyme movement, pH levels, and nutrient absorption in the gut. These fundamental biology concepts are regularly featured in medical and general science competitive exams.

Small intestine functionsBiomacromolecule breakdownStomach and digestionIntestinal bacteria

Human Digestive System Questions

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Secretin acts on the 

  1. Liver

  2. Stomach

  3. Pancreas

  4. Small intestine
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Secretin is a hormone that regulates water homeostasis. It is secreted by the duodenum. When hydrochloric acid passes from the stomach into the duodenum, secretin is released. It stimulates the acinar cells of the pancreas to secrete water and bicarbonate into the pancreatic duct. This water and bicarbonate is then drained into the duodenum.

Thus, the correct answer is 'Pancreas.'

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

CCK and secretin is secreted by

  1. Stomach

  2. Ileum

  3. Duodenum

  4. Colon
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

CCK is cholecystokinin and secretin are released by duodenum cells and CCK acts upon gallbladder for the secretion of bile while secretin stimulates stomach and they both stimulate the pancreas to secrete enzymes and hydrogen bicarbonate that neutralize acidic chyme.

So the correct option is 'Duodenum'.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Which of the following is target organ of secretin hormone ?
a. Exocrine part of pancreas
b. Endocrne part of pancreas
c. Stomach
d. Liver

  1. a, b, c & d

  2. a, c & d

  3. a only

  4. a & d
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Secretin is a hormone that regulates water homeostasis throughout the body and influences the environment of the duodenum by regulating secretions in the stomach, pancreas, and liver. It is a peptide hormone produced in the S cells of the duodenum, which are located in the intestinal glands. Secretin primarily functions to neutralize the pH in the duodenum, allowing digestive enzymes from the pancreas (e.g., pancreatic amylase and pancreatic lipase) to function optimally. Secretin targets the pancreas; pancreatic centroacinar cells have secretin receptors in their plasma membrane.


So the correct option is 'a, c & d'.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Which of the following is the function of enterogastrone ?

  1. It inhibits the secretion of gastric juice

  2. It stimulates the secretion of digestive juice in the stomach

  3. It stimulates the flow of pancreatic juice

  4. It regulates the flow of bile
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Enterogastrone is a hormone released by the duodenum that inhibits gastric motility and the secretion of gastric juice to slow down digestion when fats are present.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Which of the following hormones has effect both on stomach and pancreas.

  1. Secretin

  2. Cholecystokinin

  3. Gastrin

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Hormones are the chemicals which transfer signal from one part to the other. There are several hormones which have an effect on the stomach, pancreas as well as liver, these hormones are as follows:

  • Secretin - It is secreted in the upper lining of the stomach and also released in the pancreas. These are responsible for the secretion in the stomach and pancreas and regulates acidity.
  • Cholecystokinin - It is produced by the lining of the wall of the stomach and stimulates gall bladder to release bile. It induces the production of digestive enzymes in pancreas through pancreatic juice.
  • Gastrin - It is produced by Gastrin cells also called as G - cells. It helps in the secretion of gastric juices in the stomach and pancreas.

So, the correct option is 'All of the above'.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Secretin.

  1. Stimulates enzymes secretion by pancreas, inhibits acid secretion in stomach, stimulates gall bladder

  2. Stimulates bicarbonate secretion by pancreas, inhibits and secretion in stomach, stimulates bicarbonates secretion by liver

  3. Stimulates acid secretion in stomach, potentiates action of CCK, inhibits intestinal movement

  4. Stimulates gall bladder, inhibits acid secretion in stomach, stimulates bicarbonate secretion by pancreas
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Which part of the digestive system secretes cholecystokinin?

  1. Intestine

  2. Pancreas

  3. Stomach

  4. Gall bladder
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cholecystokinin, previously called pancreozymin, is synthesized by I-cells in the mucosal epithelium of the small intestine and secreted in the duodenum, and causes the release of digestive enzymes and bile from the pancreas and gallbladder, respectively. 

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Function of cholecystokinin is to 

  1. Contract gall bladder and release pancreatic juice

  2. Increase bile prodcution

  3. Decrease bile production

  4. Increase digestion
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Contraction of the muscle wall in the gallbladder is stimulated by the vagus nerve of the parasympathetic system and by the hormone cholecystokinin, which is produced in the upper portions of the intestine. The contractions result in the discharge of bile through the bile duct into the duodenum of the small intestine. 

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Which one is not an enzyme of digestive system?

  1. Enterokinase

  2. Amylase

  3. Trypsin

  4. Enterogastrone
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Enterogastrone is a hormone, whereas amylase, trypsin and enterokinase are enzymes. Amylase is starch splitting enzyme, while trypsin is a proteolytic enzyme. Enterokinase is a proteolytic enzyme, which acts on trypsinogen and converts it to active trypsin. Enterogastrone, is a hormone secreted by the duodenal mucosa, when fatty food is in the stomach or small intestine; it is also thought to be released, when sugars and proteins are in the intestine. Enterogastrone is transported by the bloodstream to the glands and muscles of the stomach, where it inhibits gastric movements and secretions, possibly by blocking the production or activity of gastrin, the hormone that initially causes these functions.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Secretin hormone is produced in

  1. Stomach and stimulates gastric glands

  2. Intestine and stimulates pancreatic glands

  3. Liver and stimulates gall bladder

  4. Intestine and stimulates crypts of Lieberkuhn
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Secretin is the most important hormone of digestive tract and also first hormone discovered in digestive tract. This hormone stimulates pancreas for synthesis and secretion of non enzymatic part of pancreatic juice. It also stimulates liver for secretion of bile juice and inhibit the gastric acid secretion in stomach and reduce rate of contraction of stomach.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Secretion of gastric juice is controlled by

  1. Gastrin

  2. Chlolecystokinin

  3. Enterogastrone

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

As food enters the confined space of the stomach, it starts applying pressure to the stomach wall. As food enters the stomach, the food bangs against the stomach wall, distending it. This distention causes the stomach to release gastrin. Gastrin stimulates the gastric glands to secrete more gastric juice. 

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Contraction of gall bladder is carried by

  1. Citric acid and acetyl Co-A

  2. Gastrin

  3. Cholecystokinin

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fatty acids in the lumen of the duodenum stimulate endocrine cells to release the hormone cholecystokinin (CCK). CCK stimulates contractions in the smooth muscle of the gallbladder. CCK causes relaxation of the sphincter of Oddi, allowing bile release into the duodenum.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Which of the following hormones help in contraction of gall bladder?

  1. Gastrin

  2. Secretin

  3. Cholecystokinin

  4. Insulin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fatty acids in the lumen of the duodenum stimulate endocrine cells to release the hormone cholecystokinin (CCK). CCK stimulates contractions in the smooth muscle of the gallbladder. CCK causes relaxation of the sphincter of Oddi, allowing bile release into the duodenum.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

The hormone 'secretin' stimulates secretion of

  1. Pancreatic juice

  2. Bile juice

  3. Salivary juice

  4. Gastric juice
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Secretin is the most important hormone of digestive tract. This hormone stimulates pancreas for synthesis and secretion of non enzymatic part of pancreatic juice. It also stimulates liver for secretion of bile juice and inhibit the gastric acid secretion in stomach and reduce rate of contraction of stomach.

Multiple choice zoology endocrine system and chemical co-ordination gastrointestinal tract and liver hormones of heart, kidney, liver and gastrointestinal tract coordination in human beings- chemical control

Secretion of pancreatic juice is stimulated by

  1. Gastrin

  2. Secretin

  3. Enterogastrone

  4. Enterokinase
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Secretin is the most important hormone of digestive tract. This hormone stimulates pancreas for synthesis and secretion of non enzymatic part of pancreatic juice, while pancreozymin promotes the secretion of enzymatic part of the pancreatic juice. Secretin also stimulates liver for secretion of bile juice and inhibit the gastric acid secretion in stomach and reduces rate of contraction of stomach.