1. Poliomyelitis known as Polio is caused by an enterovirus which causes paralysis of muscles. This virus has a particular affinity to ______?
[A] Muscle Cells
[B] Nerve Cells of Spinal Cord
[C] Nerve Cells of Brain
[D] None of the above
Show Answer
Correct Answer: B [Nerve Cells of Spinal Cord]
Notes:
Acute poliomyelitis is disease of anterior horn motor neurons of the spinal cord and brain stem caused by poliovirus. The virus infects and kills motor neurons in the grey matter in the ventral horn of the spinal column. Due to this, muscles of the trunk and limbs are no longer able to receive signals from the CNS, so they become weak and begin to atrophy.
2. Which among the following live tissues of the Human Eye does not have blood vessels?
[A] Sclera
[B] Cornea
[C] Choroid
[D] Iris
Show Answer
Correct Answer: B [Cornea]
Notes:
Cornea does not have blood vessels. It is the transparent part of the eye that covers the front portion of the eye. It covers the pupil, iris, and anterior chamber.
3. What is the main product of photosynthesis?
[A] Chlorophyll
[B] Carbon dioxide
[C] Oxygen
[D] Glucose
Show Answer
Correct Answer: D [Glucose]
Notes:
The main product of photosynthesis is glucose, which is the molecule that produces energy to run the processes of the cell. Oxygen is mainly a byproduct of the process of photosynthesis. Six molecules of carbon dioxide and six molecules of water are needed to produce one molecule of glucose.
4. Which of the following are longest cells of human body?
[A] Epethelial cells
[B] Pancreatic cells
[C] Nerve cells
[D] Epidermal cells
Show Answer
Correct Answer: C [Nerve cells]
Notes:
A neuron or nerve cell is a cell that carries electrical impulses. Neurons are the basic units of the nervous system. Every neuron is made of a cell body (also called a soma), dendrites and an axon. Dendrites and axons are nerve fibers. It is the longest cell of human body.
5. Bile is secreted by which of the following organs? (UPSC Prelims 1985)
[A] Liver
[B] Gall bladder
[C] Kidney
[D] Pancreas
Show Answer
Correct Answer: A [Liver]
Notes:
Bile or gall is a dark green to yellowish brown fluid, produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is produced continuously by the liver and stored and concentrated in the gallbladder.
6. At what age Wisdom teeth normally grow? (UPSC Prelims 1985)
[A] 34—40 years
[B] 12—15 years
[C] 17—30 years
[D] 40—45 years
Show Answer
Correct Answer: C [17—30 years]
Notes:
The age at which wisdom teeth come through is variable but generally occurs between late teens and early twenties. Most adults have four wisdom teeth, one in each of the four quadrants, but it is possible to have none, fewer or more in which case the extras are called supernumerary teeth.
7. The sequencing of the entire genome (the totality of all genes) of an organism was completed in 1996. Which one of the following was that organism? (UPSC Prelims 1997)
[A] Albino mouse
[B] yeast
[C] human being
[D] Plasmodium vivax
Show Answer
Correct Answer: D [Plasmodium vivax]
Notes:
Plasmodium vivax is a protozoal parasite and a human pathogen. This parasite is the most frequent and widely distributed cause of recurring malaria.
8. Neem tree has acquired industrial importance as a source of? (UPSC Prelims 1999)
[A] biopesticide and anti-fertility compound
[B] anti-fertility compound, biofertilizer and anti-cancer drug
[C] biofertilizer, biopesticide and anti- fertility compound
[D] anti-cancer drug, biopesticide and biofertilizer
Show Answer
Correct Answer: A [biopesticide and anti-fertility compound]
Notes:
Neem has been patented by India for its use as biofertilizer, biopesticide and antifertility compound as contraceptive. Neem is a natural herb that comes from the neem tree, other names for which include Azadirachta indica and Indian lilac. The extract comes from the seeds of the tree and has many different traditional uses. Neem is known for its pesticidal and insecticidal properties, but people also use it in hair and dental products.
9. A man whose blood group is not known meets with a serious accident and needs blood transfusion immediately. Which one of the blood groups mentioned below and readily available in the hospital will be safe for transfusion? (UPSC Prelims 2001)
[A] O, Rh-
[B] O, Rh+
[C] AB, Rh-
[D] AB, Rh+
Show Answer
Correct Answer: B [O, Rh+]
Notes:
There is no A and B antigen on RBC of “O– ”bloodgroup , So O, Rh– is known as universal blood donor.
10. Which branch of biology is known for the study of plant fossils?
[A] Paleobotany
[B] Morphology
[C] Lichenology
[D] Agronomy
Show Answer
Correct Answer: A [Paleobotany]
Notes:
Paleobotany is the scientific study of ancient plants using plant fossils found in sedimentary rocks.
