AIIMS Biology Questions

Which of the following are homosporous pteridophytes? I. Selaginella II. Lycopodium III. Salvinia IV. Equisetum

Which of the following is the correct scientific name of wheat derived by binominal nomenclature?

The genetic material in tobacco mosaic virus is

Select the incorrect match.

Which of the following statements is correct regarding menstrual cycle?

Match column I with column II and select the correct option from the codes given below.

Which of the following is used as bioinsecticide?

Identify the given structure.

If both parents are carriers for thalassaemia, which is an autosomal recessive disorder, what are the chances of pregnancy resulting in an affected child?

The correct sequence of stages in the evolution of modern man (Homo sapiens), is

Cornea transplant in humans is almost never rejected. This is because

Pseudostratified epithelium is found in

Identify the parts labeled A, B, C, and D in the diagram.

Match column I with column II and select the correct option from the given codes.

The given figure shows schematic plan of blood circulation in humans with labels A to D. Identify the labels along with their functions and select the correct option.

Which one of the following is not a mammalian character?

Retrogressive metamorphosis occurs in

Most animals that live in deep oceanic waters are

One hormone hastens maturity period in juvenile conifers, a second hormone controls xylem differentiation, while the third hormone increases the tolerance of plants to various stresses. They are respectively

In a 3.2 Kbp long pieces of DNA, 820 adenine bases were found. What would be the number of cytosine bases?

Match column I with column II and select the correct option from codes given below.

Some of the steps of DNA fingerprinting are given below. Identify their correct sequence from the options given. A. Electrophoresis of DNA fragments B. Hybridization with DNA probe C. Digestion of DNA by restriction endonucleases D. Autoradiography E. Blotting of DNA fragments nitrocellulose membrane

One of the following statements is incorrect with reference of biodiversity. Identify it.

The H⁻zone in the skeletal muscle fibre is due to

The volume of ‘anatomical dead space’ air is normally

Tetradynamous condition is found in

Yeast is not included in protozoans but in fungi because

As secondary growth proceeds, in a dicot stem, the thickness of

Which of the following represents the action of insulin?

Photosynthesis in C₄ plant is relatively less limited by atmospheric CO₂ levels because

The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate (ATP) is formed because

If the sequence of bases in the coding strand of a double stranded DNA is 5’-GTTCGAGTC^{-3}’, the sequence of bases in its transcript will be

A plasmolysed cell can be deplasmolysed by placing it in

One greenhouse gas contributes 14% to total global warming and another contributes 6%. These are respectively identified as

Which one of the following is correct for the transmembrane proteins in lipid bilayer of plasma membrane?

Which of the following is a group of micronutrients for plants?

Identify the labeled part in the given figure and select the correct option.

If ‘A’ represents the dominant gene and ‘a’ represents its recessive allele, which of the following would be the most likely result in the first generation offspring when Aa is crossed with aa?

The number of chromosomes present in the cells of the bread wheat, Triticum aestivum suggests that it is

Identify the labeled part in the given figure and select the correct option.

Assertion : Gap junctions perform cementing function to keep the neighbouring cells together. Reason : Tight junctions facilitate the cells to communicate with each other by connecting the cytoplasm of adjoining cells, for rapid transfer of ions, small and big molecules, etc.

Assertion : Hardy-Weinberg principle states that in the absence of disturbing influences, gene frequencies of large populations of sexually reproducing organisms do not change, provided that matings, occur at random. Reason : The disturbing influences include mutation, gene flow, genetic drift, genetic recombination and natural selection.

Assertion: Endothecium layer of anther wall plays an important role in dehiscence of anther. Reason: The presence of fibrous bands and differential expansion of inner and outer tangential walls of endothecial cells cause dehiscence of anther.

Assertion: Sphagnum is slowly carbonized, compressed, and fossilized over thousands of years to produce a dark spongy mass called peat. Reason: Peat helps to keep soil porous and it also improves water holding capacity of the soil.

Assertion: In Pleuraobrachia, eight comb like ciliary plates called comb plates are present on the body that help in locomotion. Reason: Pleurobrachia reproduces sexually and its life cycle includes cydippid larva.

Assertion: Foetal disorders can be diagnosed by chorionic villi sampling. Reason: Karyotyping can be done for mitotically dividing cells of chorionic villi.

Assertion: Consciousness is considered as the defining property of living organisms. Reason: All organisms, from the prokaryotes to the most complex eukaryotes can sense and respond to environmental stimuli.

Assertion: The technique of micropropagation has been used to introduce variations in the offspring. Reason: It is not possible to generate virus-free plants by micropropagation.

Assertion: IgM is a type of immunoglobulin which cannot cross the placenta. Reason: IgM is pentamer immunoglobulin, joined by J⁻chain.

Assertion: Pili are tubular structures present in bacteria which help in conjugation. Reason: Formation of pili is controlled by F⁺ or fertility factor.