List of top Biology Questions asked in AIIMS

The function of nitrogen fixation in Anabaena (cyanobacterium) is performed by

In the blood of an adult man the total content of haemoglobin is roughly

Which one of the following is the best stage to observe the shape, size and number of chromosomes in a cell?

The main function of the white blood cell in the human intestine system is to

Sinking of zooplankton during the day and rising to the surface at night is an example of

Animals take phosphorus from

Which of the following is true?

Which of the following statements about Spirogyra is correct?

During an allergic reaction, the binding of antigens to $IgE$ antibodies initiates a response, in which chemicals cause the dilation of blood vessels and a host of other physiological changes. Such chemicals are

Pollen mother cells (PMCs) are the first male gametophytic cells. Each PMC gives rise to two pollens.

Dark reaction occurs only at night in the stroma of chloroplast. CO fixation occurs only during C cycle.

Which of the following postulates is related with Neo-Darwinism?

Upon fertilization, what structure develops from carpel?

The outermost limiting layer of mycoplasma is made up of

Respiration is controlled by

$FAD$ is a coenzyme derived from

Cotton fibres mainly contains

Contraceptive oral pills help in birth control by

Bark refers to

The honey bee queen copulates only once in life. It can lay both fertilised and unfertilised eggs.

Protandry and protogyny ensures cross fertilization. Cross fertilization introduces variation in progeny.

Nucleus is the controlling centre of a cell. Pores in the nuclear envelop regulate the flow of materials in and out of the nucleus.

Glycolysis is the first step of respiration in which glucose completely breaks into CO and HO. In this process, there is net gain of twenty four molecules of ATP.

Cell $A$ has osmotic potential of - $18$ bars and pressure potential of $8$ bars, whereas, cell $B$ has osmotic potential of - $14$ bars and pressure potential $2$ bars. The direction of flow of water will be

Which of the following hormones is secreted by implanted blastocyst that acts on the corpus luteum in the ovary, stimulating the body to produce estrogens and progesterone to maintain the uterine lining?