All Free Biology MCQs with Answers

1931. The partly digested food is stored in________in cockroach?

• A. Gizzard
• B. Crop
• C. Hepatic caeca
• D. Rectum

Explanation: The cockroach crop is a storage chamber where ingested food, including partly digested food, is held temporarily before passing onward. The gizzard mainly grinds food, so choosing it confuses storage with mechanical digestion.

1932. Midgut in cockroach is a short narrow tube called____________?

• A. Hepatic caeca
• B. Gizzard
• C. Stomach
• D. Rectum

Explanation: In the cockroach, the midgut is the stomach, a relatively short, narrow region where digestion and absorption occur; hepatic caeca open near its anterior end. The likely mistake is choosing hepatic caeca, which are finger-like digestive glands rather than the midgut itself.

1933. Hunger contractions are _____ contractions?

• A. Antiperistalsis
• B. Peristalsis
• C. Voluntary
• D. None of these

Explanation: Hunger contractions are rhythmic peristaltic contractions of the empty stomach and intestine that help produce the sensation of hunger. The likely mistake is choosing voluntary contractions, but these movements are controlled involuntarily by smooth muscle and the enteric nervous system.

1934. A painful burning sensation produced in the chest cavity usually associated with the back flush of acidic chyme into the esophagus is__________?

• A. Pyrolysis
• B. Pyrosis
• C. Peristalsis
• D. Dyspepsia

Explanation: Pyrosis is the medical term for heartburn, caused when acidic stomach contents reflux into and irritate the oesophagus. The likely mistake is dyspepsia, which means general indigestion and is broader than the specific burning sensation of acid reflux.

1935. In planaria, numerous small branches which end blindly are called as__________?

• A. Digestive tract
• B. Intestinal caeca
• C. Hepatic caeca
• D. Both B & C

Explanation: Planaria have a branched gastrovascular cavity, and its many blind-ending branches are called intestinal caeca. The likely mistake is hepatic caeca, a term associated with digestive outgrowths in other animals, not the standard name for these planarian branches.

1936. Parasites capable of living independently of its host at times is called as ___________ parasite?

• A. Obligate
• B. Strict
• C. Facultative
• D. Endoparasite

Explanation: A facultative parasite can live independently when conditions permit but may also obtain nutrients from a host. An obligate or strict parasite depends on its host for survival, so those terms describe the opposite condition.

1937. Hepatic and Pancreatic secretions are also stimulated by a hormone produced by the intestinal mucosa. The hormone is___________?

• A. Creatin
• B. Gastrin
• C. Secretin
• D. Pepsin

Explanation: Secretin is released by the intestinal mucosa when acidic chyme enters the duodenum, and it stimulates pancreatic bicarbonate secretion and supports bile secretion by the liver. The likely mistake is gastrin, which mainly stimulates gastric gland activity and acid secretion rather than this intestinal response.

1938. Hydra is an example of ______________ feeder?

• A. Fluid
• B. Macrophagous
• C. Fluid
• D. All of these

Explanation: Hydra captures relatively large solid prey with its tentacles and digests it in the gastrovascular cavity, so it is a macrophagous feeder. The likely mistake is fluid feeding, which involves taking in dissolved nutrients rather than whole prey.

1939. ____________is about 2.4 meter in length and comprising about two fifth of the small intestine?

• A. Duodenum
• B. Jejunum
• C. Ileum
• D. Caecum

Explanation: The jejunum is approximately 2.4 metres long and forms about two-fifths of the small intestine in the description used here. The likely mistake is the ileum, which is also long but generally accounts for the remaining larger portion of the small intestine.

1940. Certain types of whales are also __________ feeder?

• A. Fluid
• B. Macrophagous
• C. Filter
• D. None of these

Explanation: Many whales use baleen to strain plankton and small organisms from large volumes of water, making them filter feeders. The likely mistake is macrophagous feeding, which involves capturing relatively large individual food items rather than filtering suspended particles.