Biology - Online Test
Q1. AIDS is caused by Human immuno deficiency virus (HIV) which is a member of group of virus called
Answer : Option B
Explaination / Solution:
Retrovirus, any of a group of viruses that belong to the family Retroviridae and that characteristically carry their genetic blueprint in the form of ribonucleic acid (RNA). Retroviruses are named for an enzyme known as reverse transcriptase, which was discovered independently in 1971 by American virologists Howard Temin and David Baltimore.
HIV virus belongs to this group as its genetic material is also RNA.
Q2. The vestibular apparatus is composed of
Answer : Option B
Explaination / Solution:
The vestibular apparatus is composed of three semicircular canals and the otolith organ consisting of the saccule and utricle.
Q3. A plant producing seeds but lacking flowers is
Answer : Option C
Explaination / Solution:
Gymnosperms produces seeds without formation of flowers. The gymnosperms (gymnos : naked, sperma : seeds) are plants in which the ovules are not enclosed by any ovary wall and remain exposed, both before and after fertilisation. The seeds that develop post-fertilisation, are not covered, i.e., are naked.
Q4. The plasma membrane consists mainly of
Answer : Option D
Explaination / Solution:
The plasma membrane is composed of lipids that are arranged in a bilayer. Also, the lipids are arranged within the membrane with the polar head towards the outer sides and the hydrophobic tails towards the inner part.
The membrane proteins can be classified as integral or peripheral. Peripheral proteins lie on the surface.
Q5. The strand of DNA that forms mRNA is called
Answer : Option D
Explaination / Solution:
During transcription, only one of the two DNA strands is copied. This is called the template strand because it acts as a template for the mRNA that is being assembled by the ribosomes. The sequence of the mRNA is complementary to the sequence of the template strand.
It is also known as sense strand.
Q6. In cells, ATP is synthesized in
Answer : Option C
Explaination / Solution:
ATP is synthesized by cells (in mitochondria and chloroplasts) is named phosphorylation.
Q7. Which of the following pair of factors are considered favourable for the formation of oxyhaemoglobin?
Answer : Option C
Explaination / Solution:
In the alveoli, where there is high , low , lesser concentration and lower temperature, the factors are all favourable for the formation of oxyhaemoglobin.
Q8. Which one is an alternate source of proteins for animals and human nutrition?
Answer : Option A
Explaination / Solution:
Alternate source of proteins for animals and human nutrition is single cell protein. Microbes are grown on industrial scale as source of good protein. Microbes like Spirulina on waste water of potato processing plants.
Q9. Species which suffered a near-extinction from ingesting the carrion of diclofenac-treated cattle is/are:
Answer : Option D
Explaination / Solution:
These include the Asiatic lion, the Bengal tiger, the snow leopard and the Indian white-rumped vulture, which, by ingesting the carrion of diclofenac-laced cattle, nearly went extinct.
Q10. A dwarf person showing stunted growth and mental retardation both, is a result of hyposecretion of
Answer : Option A
Explaination / Solution:
Hypothyroidism causes defective development and maturation of the growing baby leading to stunted growth (cretinism), mental retardation, low intelligence quotient, abnormal skin, deaf-mutism, etc.
