Questions

Fragmentation occurs in a dynamic memory allocation system when many of the free blocks are too small to satisfy any request.

CTRL + B is computer keyboard shortcut bolds selected text.

CTRL + I is used for making the selected text italic

SHIFT + CTRL + S used for SAVE AS option for any document or file.

A gamma ray or gamma radiation, is a penetrating electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves and so imparts the highest photon energy.

Gamma rays are emanations that have neither mass nor charge.

In the above options, sperms are the haploid cells. In humans, haploid cells are those have only half the number of usual number of chromosomes. Sperm, gamates and egg cells are the haploid cells examples.

The statements true about viruses are :

1. The capsid enters the host cell if the virus is enveloped.

2. Enveloped viruses bud from the host cell. 

3. HIV contains reverse transcriptase.

4. A retrovirus contains RNA.

The principal hormone secreted by the corpus luteum is progesterone. Menstruation is triggered by a drop in the levels of progesterone.