Quiz 223 – UPSC Previous Year’s Biology Questions with Explained Answers

Octopus is:

(a) an arthropod

(b) an echinoderm

(c) a hemichordate

(d) a mollusk


Octopus is an animal of phylum Mollusca. Most molluscls have hard shell that protects their soft body, although in some of them, the shell is missing or hardly visible e.g., octopus, oysters etc.

Ans- (d)


Consider the following plants:

  1. Bougainvillea
  2. Carnations
  3. Cocoa
  4. Grapes

Which of these plants are propagated by stem cuttings?

(a) 1 and 2

(b) 2, 3 and 4

(c) 1, 3 and 4

(d) 1, 2, 3 and 4


Stem cuttings are employed in case of Rosa, Clerodendron, Durante, Citrus, Bougainvillea, Tea, Coffee and Cocoa.

Ans- (c)


Consider the following statements:

  1. Molasses is a by-product of sugar production process.
  2. Bagasse obtained in the sugar mills is used as a fuel in the boilers to generate steam for the sugar factories.
  3. Sugar can only be produced from sugarcane as the raw material.

Which of these statements are correct?

(a) 1 and 2

(b) 2 and 3

(c) 1 and 3

(d) 1, 2 and 3


Statements 3 is not correct because sugar can also be produced by sugarbeet. Other two statements are true.

Ans- (a)


The hormone insulin is a:

(a) Glycolipid

(b) Fatty acid

(c) Peptide

(d) Sterol


Insulin, produced islets of langerhans of the pancreas, regulates the carbohydrates metabolism, fats and starch in body. The hormone insulin is a peptide.

Ans- (c)


In which organ of the human body, are the lymphocyte cells formed?

(a) Liver

(b) Long bone

(c) Pancreas

(d) Spleen


Lymphocytes are smallest of WBC, a little larger than RBCs. They have large nucleus. It is about 25% of total WBC. Lymphocyte cells found in large bones, produce antibodies, which kill or neutralize the germs or poison from them.

Ans- (b)


Assertion (A): All the proteins in our food are digested in small intestine only.

Reason (R): The protein-digesting enzyme from pancreas are released into small intestine.

(a) A and R are true and R is the correct explanation of A.

(b) A and R are true but R is not the correct explanation of A.

(c) A is true, but R is false

(d) A is false, but R is true


Protein digestion occurs in stomach as well as in small intestine but most protein digestion occurs in the upper small intestine, in the duodenum and  jejunum under the influence of proteolytic enzymes from pancreatic secretion immediately on entering the small intestine from the stomach.

Ans- (d)


Which of the following diseases of mulching animal are infectious?

  1. Foot and mouth disease
  2. Anthrax
  3. Black Quarter
  4. Cowpox

Select the correct answer using the codes given below:

(a) 1, 2 and 3

(b) 2, 3 and 4

(c) 1 and 4

(d) 1, 2, 3 and 4


Black Quarter is a disease which is found in horse.

Ans- (c)


Pneumoconiosis affects the workers who work mainly in:

(a) Tanneries

(b) Coalmining industry

(c) Distilleries

(d) Glass industry


Particulate matter from processing industries such as mine dust, cotton dust, iron mill dust, flour mill dust etc. cause pneumoconiosis, byssinosis, emphysaema, siderosis and other pulmonary diseases.

Ans- (b)


Which one of the following statements is not correct?

(a) Milk contains none of the B-vitamins.

(b) Vitamin-A (retinol) deficiency leads to dry and scaly skin.

(c) One of the symptoms of scurvy is pain in the joints.

(d) Vitamin B1 (thiamine) deficiency can lead to heart failure.


Statement (a) is wrong. Milk contains vitamin B2 (riboflavin).

Ans- (a)


Ticks and mites are actually:

(a) Arachnids

(b) Crustaceans

(c) Insects

(d) Myriapods


Scorpion, spider, tick and mites occur under class Arachnisa of phylum Arthropoda.

Ans- (a)

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