Biology · Science General
Human Digestive System
1,953 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
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multicellular
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extra-cellular
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unicellular
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cellular
B
Correct answer
Explanation
Extracellular digestion occurs when an organism secretes digestive enzymes onto its food source outside its body. The enzymes break down complex molecules into simpler ones, which are then absorbed. This is the primary method used by fungi to obtain nutrients.
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Mouth
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Oesophagus
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Small intestine
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Stomach
B
Correct answer
Explanation
From mouth, food is transported to the stomach through the food pipe or oesophagus. However, no digestion takes place in the oesophagus. It simply pushes the food into the stomach through rythmic contractions.
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To increase the surface area for absorption of minerals
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To increase the surface area for digestion of food
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To facilitate the diffusion of gases
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To regulate the ejection of waste material
A
Correct answer
Explanation
Large intestine has numerous finger-like projections called villi, which increase the surface area for absorption of water and minerals.
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To digest starch
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To emulsify fats
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To decrease pH of food
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To digest proteins
B
Correct answer
Explanation
Bile juice helps to break down the larger fat globules into smaller globules. Thus, it helps in the emulsification of fat.
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Because if they are present in active form, they will digest the walls of the alimentary canal
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Because if they are present in active form, they will inhibit the digestion of starch
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Because if they are present in active form, they will inhibit the activity of other enzymes, like lipase
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Because if they are present in active form, they will increase the acidic concentration in the small intestine
A
Correct answer
Explanation
If pepsin and trypsin are released in active form in the alimentary canal, they will digest the walls of the alimentary canal if food is not available for digestion.
Which of the following correctly represents the enzymes with their functions?
|
|
| (a) Amylase |
(1) Breakdown of fats |
| (b) Trypsin |
(2) Breakdown of lactose |
| (c) Lipase |
(3) Breakdown of starch |
| (d) Lactase |
(4) Breakdown of protein |
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(a) – (4), (b) – (3), (c) – (1), (d) – (2)
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(a) – (1), (b) – (3), (c) – (4), (d) – (2)
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(a) – (3), (b) – (1), (c) – (3), (d) – (2)
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(a) – (3), (b) – (4), (c) – (1), (d) – (2)
D
Correct answer
Explanation
|
|
| (a) Amylase |
(3) Breakdown of starch |
| (b) Trypsin |
(4) Breakdown of proteins |
| (c) Lipase |
(1) Breakdown of fats |
| (d) Lactase |
(2) Breakdown of lactose |
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Oesophagus
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Mouth
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Stomach
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Small intestine
B
Correct answer
Explanation
The digestion of food starts from mouth, where the food is chewed and is mixed with saliva. Saliva contains an enzyme (salivary amylase) which converts starch present in the food into simple carbohydrates.
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liver and muscles
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liver and spleen
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spleen and gall bladder
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spleen and muscles
A
Correct answer
Explanation
Glycogen is the primary storage form of glucose in animals and is stored primarily in the liver and skeletal muscles.
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Gall bladder
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Liver
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Stomach
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Pancreas
A
Correct answer
Explanation
Bile is produced by the liver but is stored and concentrated in the gall bladder before being released into the small intestine to aid digestion. Therefore, the gall bladder is the collection site.
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Cholecystokinin and pancreozymin
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Pepsin and rennin
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Pancreozymin and pepsin
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Rennin and cholecystokinin
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Pepsin and cholecystokinin
A
Correct answer
Explanation
Cholecystokinin and pancreozymin are two hormones that stimulate the secretion of pancreatic juice. Cholecystokinin causes contraction of the gall bladder and discharges the bile into the duodenum. Pancreozymin also stimulates the pancreas to secrete insulin and glucagon.
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Liver
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Salivery gland
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Glands of small intestine
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Pancreas
A
Correct answer
Explanation
The liver produces bile, which emulsifies fats, but bile does not contain digestive enzymes. The other listed organs all secrete specific enzymes for digestion.
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Oesophagus
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Pancreas
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Spleen
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Large Intestine
B
Correct answer
Explanation
The pancreas is a dual-function organ. It acts as an exocrine gland by secreting digestive enzymes into the small intestine and as an endocrine gland by secreting hormones like insulin and glucagon into the bloodstream.
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an enzyme
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a low calorie sweetener
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cholestrol reducing
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produced by animal
B
Correct answer
Explanation
Correct. This protein is as sweet as sugar and is used as a low calorie swetner
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holotrophy
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osmotrophy
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phagotrophy
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chemotrophy
B
Correct answer
Explanation
Osmotrophy is the uptake of dissolved organic compounds by osmosis for nutrition, digestion occurs outside the body of the organism.
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chyle
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chyme
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bile
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none of these
C
Correct answer
Explanation
Bile is produced by the liver and stored in the gallbladder. It contains bile salts that emulsify fats, aiding digestion, but it does not contain digestive enzymes itself.