31. Chloroquine is given to treat which of the following disease?
[A] Malaria
[B] Tuberculosis
[C] Tetanus
[D] AIDS
Show Answer
Correct Answer: A [Malaria]
Notes:
Chloroquine is given to treat Malaria disease. Quinine (from the bark of Cinchona), camaquine, primaquine, and daraprim are also given to treat Malaria.
32. In most species, mitochondrial DNA is passed down from which of the following?
[A] DNA
[B] Mother and Father
[C] Father
[D] Mother
Show Answer
Correct Answer: D [Mother]
Notes:
In most of the species, mitochondrial DNA is passed down from Mother.
33. Which chemical fertilizer is needed for better rhizobial nitrogen fixation?
[A] Phosphorus
[B] Potassium
[C] Calcium
[D] Sodium
Show Answer
Correct Answer: A [Phosphorus]
Notes:
Phosphorus is the essential chemical fertilizer for better rhizobial nitrogen fixation.
34. What is an autonomously repeating circular extra-chromosomal DNA?
[A] Bacteria
[B] Nitrogenous base
[C] RNA
[D] Plasmid
Show Answer
Correct Answer: D [Plasmid]
Notes:
A plasmid is an autonomously repeating circular extra-chromosomal DNA. They naturally exist in bacterial cells, and they also occur in some eukaryotes.
35. Approximately how many pairs are there in the human genome?
[A] 6 billion base pairs
[B] 5 billion base pairs
[C] 3 billion base pairs
[D] 4 billion base pairs
Show Answer
Correct Answer: C [3 billion base pairs]
Notes:
Approximately 3 billion base pairs are there in the human genome. The complete set of nucleic acid sequences for humans encoded as DNA within 23 chromosome pairs in the cell nucleus and a small DNA molecule found within individual mitochondria is called the human genome.
36. Which chemical is used to obtain a precipitate of pure DNA?
[A] Methanol
[B] Ether
[C] HCl
[D] Ethanol
Show Answer
Correct Answer: D [Ethanol]
Notes:
Ethanol is used to obtain a precipitate of pure DNA. Renewable fuel made from corn and other plant materials is called ethanol.
37. Which of the following structures are present in the throat to prevent the air passage from collapsing?
[A] Rings of cartilage
[B] Rings of muscle
[C] Rings of bone
[D] Rings of connective tissue
Show Answer
Correct Answer: A [Rings of cartilage]
Notes:
Rings of cartilage are present in the throat, specifically in the trachea or windpipe, to ensure that the air passage does not collapse. These semi-circular rings provide the necessary structural support to keep the airway open regardless of pressure changes that occur during breathing. This is very important for maintaining a clear, open path for air to flow into our lungs for respiration.
38. Fermentation is a type of ____ process:
[A] Exothermic Reaction
[B] Aerobic Respiration
[C] Anaerobic Respiration
[D] Transpiration
Show Answer
Correct Answer: C [Anaerobic Respiration]
Notes:
Fermentation in food processing is the process of converting carbohydrates to alcohol or organic acids using microorganisms—yeasts or bacteria—under anaerobic conditions. It also occurs in oxygen-starved muscle cells, as in the case of lactic acid fermentation.
39. Which of the following statement is incorrect?
[A] Budding is not possible in hydra
[B] Hydra have only a sexual reproduction
[C] Most frogs are an oviparous animals
[D] Internal fertilisation takes place in hens
Show Answer
Correct Answer: B [Hydra have only a sexual reproduction]
Notes:
Hydra is radially symmetrical, that is, the parts of its body are arranged in a circle around a central median axis passing through the mouth. Hydra reproduces by asexual and sexual methods. Asexual reproduction takes place either by budding or by fission.
40. If a healthy freshwater fish is placed in salt water, what will be the expected consequence?
[A] The fish becomes dehydrated and dies
[B] The fish becomes bloated and dies
[C] The fish suffers from fungal or bacterial disease and dies
[D] There is no observable effect on the fish provided there is sufficient food
Show Answer
Correct Answer: A [The fish becomes dehydrated and dies]
Notes:
When freshwater fish is placed in salt water, the water molecules contained in the fish’s body would pass through the cell membranes of the fish, causing the fish to lose water by osmosis. This sudden change in the molecular makeup of the fish would cause the fish to undergo severe dehydration followed by death.
