Biology · Human Health and Diseases · NEET
No. HIV is the virus (Human Immunodeficiency Virus). AIDS is the syndrome (disease) that HIV causes after it destroys many helper T-cells. HIV infection comes first; AIDS is the late stage. This exact difference is a favourite NEET trap, so remember: virus = HIV, disease = AIDS.
AIDS = Acquired Immuno Deficiency Syndrome. 'Acquired' means you get it during life (it is not congenital, not from birth). 'Syndrome' means a group of symptoms. HIV = Human Immunodeficiency Virus, the retrovirus that causes AIDS.
A retrovirus has an RNA genome and the enzyme reverse transcriptase. Inside the host cell, reverse transcriptase makes DNA from the viral RNA (the reverse of the normal DNA-to-RNA flow). NCERT names HIV as 'a member of a group of viruses called retrovirus, which have an envelope enclosing the RNA genome.'
No. Being HIV-positive means the virus is in the body. AIDS is diagnosed only later, when helper T-cell numbers fall very low and the person starts getting other infections. A person can stay HIV-positive without AIDS for years. NEET often tests this distinction directly.
No. The word 'Acquired' tells you it is picked up during a person's lifetime, not present from birth. It spreads mainly by sexual contact, contaminated blood, shared needles, or from infected mother to baby. Calling it congenital is wrong for NEET.
HIV has an outer envelope enclosing an RNA genome. The particle carries two identical single-stranded RNA molecules and two molecules of the enzyme reverse transcriptase. This exact fact was tested in NEET 2016, so memorise 'two RNA + two reverse transcriptase, enveloped.'
Which of the following is correct regarding AIDS causative agent HIV?
Try the real previous-year questions from this chapter — each with the answer and a full solution.
AIDS is caused by HIV (Human Immunodeficiency Virus), which belongs to a group of viruses called retroviruses. Its RNA genome is enclosed in an envelope.
HIV progressively destroys helper T-lymphocytes (TH cells). As their number falls, immunity collapses and the person becomes open to many infections. The detailed replication process is covered on the next page, HIV replication in the body.
NCERT states AIDS was first reported in 1981. Over the following decades it spread worldwide and killed more than 25 million people.
'Syndrome' means a group of symptoms occurring together. AIDS is a set of symptoms and infections that appear because the immune system is badly damaged, so it is called a syndrome.
