Biology Quiz 4

The virus without capsid but only with nucleic acids is called Nucleoid. Nucleoid represents the viral chromosome. It is made of a single molecule of nucleic acid. Nucleoid is the infective part of the virus. The nucleic acid is either DNA or RNA but never both.

The normal cholesterol levels are different depending on age and sex. In adult human blood, It is between 180-200 milligrams per deciliter (mg/dL).

Hepatitis is a viral disease caused by hepatitis viruses A, B, C, D, and E. It infects liver cells and causes inflammation.

Fish growth and activity usually require 5-6 mg/L of dissolved oxygen. Dissolved oxygen levels below 3 mg/L are stressful to most aquatic organisms. Healthy water should generally have dissolved oxygen concentrations above 6.5-8 mg/L and between about 80-120 percent.

Barr body is the inactive X-chromosome in the somatic cells of mammalian females. Human females have two X chromosomes, while males have one X and one Y. In all of the female somatic cells, which don't take part in sexual reproduction, one of the X chromosomes is active, and the other is inactivated in a process called lyonization, becoming the Barr body.

Diphtheria is a highly contagious, infectious disease caused by the bacteria Corynebacterium diphtheriae. It is a serious bacterial infection that usually affects the mucous membranes of the nose and throat.

Gregor Mendel (1822-1884) discovered the basic principles of heredity through experiments with pea plants, long before the discovery of DNA and genes.

Vermicomposting is done by worms. It is the process by which worms are used to convert organic materials (usually wastes) into a humus-like material known as vermin-compost.

The pituitary gland is a small organ at the base of the brain. It produces and releases several hormones that help carry out important bodily functions. Through secretion of its hormones, the pituitary gland controls metabolism, growth, sexual maturation, reproduction, blood pressure and many other vital physical functions and processes.

Allantois of Embryo helps in excretion. The allantois is a hollow sac-like structure filled with clear fluid that forms part of a developing amniote's conceptus (which consists of all embryonic and extra-embryonic tissues). It helps the embryo exchange gases and handles liquid waste.