MCQs on Radiation Biology and Safety - Part 1

# Among the natural radiation, the one that contributes to more radiation exposure of general population:
A. Cosmic
B. Terrestrial
C. Radon
D. Consumer products

# X rays cause radiation damage primarily by their property of:
A. Penetration
B. Radioactivity
C. Electromagnetic induction
D. Ionisation

Most radiosensitive cells:

# The most radiosensitive cells in the body are:
A. Endothelial cells
B. Epithelial cells
C. Red blood cells
D. White blood cells

The correct answer is D. White blood cells.

Identical twins develop from:

# Identical twins are produced by fertilization of:
A. 1 ovum by 1 sperm
B. 2 ova by 1 sperm
C. 1 ovum by 2 sperms
D. 2 ova by 2 sperms

The correct answer is: A. 1 ovum by 1 sperm

Twins can be either monozygotic ('identical'), meaning that they develop from one zygote, which splits and forms two embryos, or dizygotic ('non-identical' or 'fraternal'), meaning that each twin develops from a separate egg and each egg is fertilized by its own sperm cell.

Children oral cavity wounds causes

# The leading cause of childhood gingivostomatitis in children aged 1 to 3 is:
A. Herpes Simplex
B. Chicken pox
C. Influenza
D. Rubella

The correct answer is A. Herpes simplex

The primary infection (primary herpetic gingivostomatitis) usually occurs in a chlld under ten years of age who has had no contact with the Type I herpes simplex virus and who therefore has no neutralizing antibodies. It may also affect young adults (15-25). Nearly all primary infections are of the subclinical type (they may only have flu- like symptoms) and one or two mild sores in the mouth which go unnoticed by the parents.

In other children, the primary infection may be manifested by acute symptoms (acute herpetic gingivostomatitis). These include fever; irritability; cervical lymphadenopathy; fiery red gingival tissues; and small, yellowish vesicles that rupture and result in painful ulcers on the free and attached mucosa. The most serious potential problem in a child with this infection is dehydration due to the child not wanting to eat or drink because of the pain.

Treatment is supportive and aimed toward the relief of the acute symptoms so that fluid and nutritional intake can be maintained. Primary herpetic gingivostomatitis usually runs a course of 14-20 days and the ulcers heal without scarring.

Remember: Of all of the herpes viruses, herpes simplex viruses 1 and 2 cause manifestations of recurrent infection in otherwise healthy people.