Science & Technology › Biology – UPSC Prelims PYQs

Among living organisms,

which one of the following is the most responsible factor for bringing about the origin of a new species?

Ticks and mites are actually

With reference to the blood in a normal person, which one of the following statements is correct?

Consider the following plants:

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

Which of these plants are propagated by stem cuttings?

In the context of the organic evolution, the loss of limbs of snakes is explained by the phenomenon of

With reference to the human body, consider the following statements:

1. The production of somatotropin goes up when a person exercises.
2. Men’s testes produce progesterone.
3. Women’s adrenal glands secrete testosterone.
4. Stress causes the adrenals to release very little cortisol compared to usual.

Which of these statements are correct?

In a bisexual flower, if androecium and gynaecium mature at different times, the phenomenon is known as

Which one of the following statements is correct?

Assertion (A): Drinking of whisky increases the frequency of urination.

Reason (R): Alcohol intake speeds up the secretion of vasopressin in the body.

Which of the following cell organelles play the most significant role in protein synthesis?

The cellular and molecular control of programmed cell death is known as

Which organelle in the cell, other than nucleus, contains DNA?

Epiphytes are plants which depend on other plants for

Antigen is a substance which

Match List I with List II

and select the correct answer using the codes given below the Lists:

List I (Bone) I. Breast-bone II. Collar-bone III. Knee-cap IV. Shoulder blade

List II (Name) A) Clavicle B) Patella C) Scapula D) Sternum

Consider the following statements: I. Tapeworm is a hermaphrodite. II. Round-worm has separate sexes. III. Filaria is caused by a nematode. IV. Guinea worm is an annelid.

Which of these are correct?

A man whose blood group is not known meets with a serious accident and needs blood transfusion immediately. Which one of the blood groups mentioned below and readily available in the hospital will be safe for transfusion?

Match List I with List II

and select the correct answer using the codes given below the Lists:

List I (Substance) I. Ptyalin II. Pepsin III. Renin IV. Oxytocin

List II (Physiological role) A) Converts angiotensinogen in blood into angiotensin B) Digests starch C) Digests proteins D) Hydrolyses fats E) Induces contraction of smooth muscles

At which stage in its life-cycle does the silkworm yield the fibre of commerce?

Match List I (Endocrine glands) with List II (Hormones secreted) and select the correct answer using the codes given below the Lists:

List I I. Gonads II. Pituitary III. Pancreas IV. Adrenal

List II A) Insulin B) Progesterone C) Growth hormones D) Cortisone

Codes:

The sensation of fatigue in the muscles after prolonged strenuous physical work is caused by

Match the hormones in List I with items in List II and select the correct answer using the codes given below the Lists:

List I I. Adrenaline II. Estrogen III. Insulin IV. Pheromones

List II A) Anger, fear, danger B) Attracting partners through sense of smell C) Females D) Glucose

Codes:

Neem tree has acquired industrial importance as a source of

For which one of the following is capillarity not the only reason?

When ants bite, they inject

Match List I with List II

and select the correct answer using the codes given below the lists:

List I I. Fruit II. Seed III. Wood IV. Starch

List II A) Ovule

B) Leaf

C) Stem

D) Ovary

Which one of the following statements regarding starch and cellulose is NOT correct?

The complete conversion of glucose in the presence of oxygen into carbon dioxide and water with release of energy is called

The pituitary gland by virtue of its tropic hormones controls the secretory activity of other endocrine glands.

Which one of the following endocrine glands can function independent of the pituitary gland?

Oxygen transportation in a human body takes place through I. Blood II. Lungs III. Tissue The correct sequence of transportation is

Corpus luteum is a mass of cells found in

Alpha-keratin is a protein present in

Arteries supplying blood to the heart are called

Antigen is a substance which

Which one of the following is a modified stem?

Fat present below the skin surface in our body acts as a barrier against

Which one of the following is NOT an essential micronutrient for plants?

Living organisms require at least 27 elements, of which 15 are metals. Among these, those required in major quantities include

Match List I with List II

and select the correct answer using the codes given below the lists:

List I I. Vitamin II. Enzyme III. Hormone IV. Protein

List II A. Pepsin B. Carotene C. Keratin D. Progesterone

Match List I (Physiological processes) with List II (Cell organelles) and select the correct answer by using the codes given below the lists:

List I I. Photosynthesis II. Mineral uptake III. Respiration IV. Protein Synthesis

List II A) Plasma membrane B) Chloroplast C) Mitochondria D) Ribosomes

Codes:

The Nobel Prize for deciphering the language of bees was awarded to

A person with ‘AB’ blood group is sometimes called a universal recipient because of the

Which one of the following is a membrane that protects the developing embryo from desiccation?

Most of the desert plants bloom during night time because

The only snake that builds a nest is

Which of the following elements are present in all proteins? I. Carbon II. Hydrogen III. Oxygen IV. Nitrogen

Select the correct answer from the codes given below:

Which one of the following hormones contains iodine?