Free Digestion MCQs with Answers
680 Digestion MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The human digestive system covers the organs from mouth to anus, the movement of food, and the mechanical and chemical breakdown of carbohydrates, proteins and fats. It also includes the roles of digestive enzymes, bile, absorption through intestinal villi, and the assimilation of nutrients by body cells.
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Read the Digestion notesFree MDCAT chapter notes with key terms680 questions · page 7 of 34
- A. 6CO2 + 12H2O + light + chlorophyll -> C6H12 + 6H2O + 6CO2
- B. 2H2S + CO2 + light -> (CH2O)n + H2O + 2S
- C. NH4 + 3O2 + light -> 2NO2 + 2H2O + 4H+ + energy
- D. CH3COOH + enzyme -> CH3CHO + CO2
- E. 5GA3P + 3ATP -> 3RuBP + 2Pi
Explanation: The word Chemoautotrophic nutrition means energy produced with chemical reactions taking place.
Correct answer: NH4 + 3O2 + light -> 2NO2 + 2H2O + 4H+ + energy- A. Bacteria
- B. Yeast
- C. Fungi
- D. Algae
- E. Virus
Explanation: Zymase is an enzyme complex that catalyzes the fermentation of sugar into ethanol and carbon dioxide. It occurs naturally in yeasts.
Correct answer: Yeast123. Bile is used in:
- A. Protein digestion
- B. Starch digestion
- C. Fat emulsification
- D. Both A and B
Explanation: Bile juice (containing bile salts) is secreted from the liver stored in gallbladder and secreted into intestine via bile duct.
Correct answer: Fat emulsification- A. Rennin
- B. Trypsin
- C. Pepsin
- D. Lipase
Explanation: Chymosin, known also as RENNIN, is a proteolytic enzyme synthesized by chief cells in the stomach.
Correct answer: Rennin- A. Hydra
- B. Jellyfish
- C. Flatworms
- D. All of these
Explanation: Internal digestion occurs when food is digested within the body of the organism while external digestion is when an organism secretes…
Correct answer: All of these- A. Rennin
- B. Amylase
- C. Lipase
- D. None of these options are correct.
Explanation: Milk-drinking babies have additional enzyme rennin because it causes solidification of the milk and solid milk is digested slowly so even…
Correct answer: Rennin- A. Hypothalamus
- B. Hormones
- C. Medulla oblongata
- D. Sympathetic nervous system
Explanation: The swallowing CPG is located within the medulla oblongata. Swallowing is indeed a primitive reflex, which means that it is present in all…
Correct answer: Medulla oblongata- A. Obesity
- B. Malnutrition
- C. Anorexia Nervosa
- D. Dyspepsia
- E. Peptic ulcer
Explanation: An eating disorder characterized by markedly reduced appetite or total aversion to food. Anorexia is a serious psychological disorder.
Correct answer: Anorexia Nervosa- A. H2O
- B. CO2
- C. K
- D. P
- E. N
Explanation: Plants store soluble phosphate in the form of phosphorus and the symbol is "P".
Correct answer: P- A. 1 and 2
- B. 2 and 3
- C. 3 and 4
- D. 4 and 1
Explanation: Incisor and canine are used to cut and chew. Premolar and Molar are used for grinding the food
Correct answer: 1 and 2- A. Decomposers (e.g. bacteria and fungi)
- B. Producers (e.g. green plants)
- C. Primary consumers (e.g. mice)
- D. Secondary consumers (e.g. snakes)
- E. Tertiary consumers (e.g. hawks)
Explanation: Producers take in carbon dioxide and produce oxygen by the process of photosynthesis, no other organism has this ability, so the removal…
Correct answer: Producers (e.g. green plants)- A. Hepatitis
- B. Cholera
- C. Malaria
- D. Beriberi
- E. Alzheimer's Disease
Explanation: Beriberi is caused by the deficiency of Vitamin-B1, which is a thiamine. All other diseases mentioned do not apply.
Correct answer: Beriberi- A. A
- B. B
- C. C
- D. D
Explanation: Scurvy is caused due to a deficiency of vitamin C (ascorbic acid). Vitamin C plays a crucial role in the synthesis of collagen, which is…
Correct answer: C- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Roaches use their antennae to locate food and estimate the distance and height of any obstacles in front of them.
Correct answer: Option B- A. duodenum -> jejunum -> ileum -> rectum -> colon
- B. ileum -> duodenum -> colon -> jejunum -> rectum
- C. ileum -> duodenum -> jejunum -> rectum -> colon
- D. colon -> duodenum -> ileum -> rectum -> jejunum
- E. duodenum -> jejunum -> ileum -> colon -> rectum
Explanation: After leaving the stomach, the food enters the small intestine through a pyloric sphincter.
Correct answer: duodenum -> jejunum -> ileum -> colon -> rectum- A. Small intestine
- B. Stomach
- C. Liver
- D. Large intestine
- E. Oesophagus
Explanation: Liver is never in contact with the food, though it does produce some digestive enzymes.
Correct answer: Liver- A. Water
- B. Soil
- C. Air
- D. Blood
Explanation: Filter feeders primarily extract food particles from water. They possess specialized structures or mechanisms to filter out and capture…
Correct answer: Water- A. 1 to 2%
- B. 5 to 10 %
- C. 30 to 40%
- D. 10 to 15%
Explanation: Fatty liver disease is a common condition caused by the storage of extra fat in the liver.
Correct answer: 5 to 10 %- A. Ectoderm
- B. Endoderm
- C. Mesoderm
- D. None of these
Explanation: The digestive system in vertebrates is primarily formed by the endoderm, which is one of the three primary germ layers in the early…
Correct answer: Endoderm- A. Colon
- B. Small intestine
- C. Large intestine
- D. Stomach
- E. None of the above
Explanation: In vertebrates absorption occurs mostly in the small intestine, although some absorption occurs in the stomach and large intestine also.
Correct answer: Small intestine