General Science - Biology MCQs
41. Time required for the organism to eliminate 50% the total body burden or tissue concentration of chemical is referred as ____:
[A] Threshold limit time
[B] Residual period
[C] Half-time life
[D] Half-life period
Show Answer
Correct Answer: D [Half-life period]
Notes:
Time required for the organism to eliminate 50 per cent of the total body burden or tissue concentration of chemical is referred to as Half Life Period. A biological half-life or elimination half-life is the time it takes for a substance (drug, radioactive nuclide, or other) to lose one-half of its pharmacologic, physiologic, or radiological activity.
42. Haematopoiesis take place in ____:
[A] Lungs
[B] Liver
[C] Pancreas
[D] Bone marrow
Show Answer
Correct Answer: D [Bone marrow]
Notes:
Haematopoiesis refers to the formation of blood cellular components. The sites where haematopoiesis occurs change as during embryonic development, it is liver but after birth in youngs and adults, the site is bone marrow of the long bones.
43. Webbed neck is a characteristic of _____:
[A] Turners syndrome
[B] Downs syndrome
[C] Klinefelters syndrome
[D] Cri-du-chat syndrome
Show Answer
Correct Answer: A [Turners syndrome]
Notes:
A webbed neck, or pterygium colli deformity, is a congenital skin fold that runs along the sides of the neck down to the shoulders. It is a feature of Turner syndrome and Noonan syndrome, as well as the rarer Klippel-Feil syndrome. Turner Syndrome (TS) is a condition in which a female is partly or completely missing an X chromosome.
44. Slow-growing large coloured patches on the bark of trees are the examples of symbioticlife forms called _____:
[A] Aphids
[B] Lichens
[C] Egrets
[D] Shrimps
Show Answer
Correct Answer: B [Lichens]
Notes:
Lichen is a symbiotic life form, that grows on the bark of tree as colored patches.It is an association between blue green algae and fungi. The combined lichen has properties different from those of its component organisms.
45. Intercalary meristems are found in ____:
[A] Node
[B] Lateral bud
[C] Terminal bud
[D] Inter node
Show Answer
Correct Answer: D [Inter node]
Notes:
Intercalary meristem is meristem at the base of the internode in monocot stems (particularly grass stems). Only the apical meristem is active. If the tip of the stem is removed, the uppermost intact intercalary meristem becomes the apical meristem and starts intercalary growth. The intended removal of apical meristen to induce branching is called apical dominance. It supports branching in plants.
46. Beak is formed by _____:
[A] Cheeks
[B] Jaws
[C] Teeth
[D] None of the above
Show Answer
Correct Answer: B [Jaws]
Notes:
Although beaks vary significantly in size and shape from species to species, their underlying structures have a similar pattern. All beaks without teeth are composed of two jaws, generally known as the upper mandible (or maxilla) and lower mandible (or mandible).
47. Teeth and Bones acquire strength and rigidity from _____:
[A] Calcium
[B] Fluorine
[C] Chlorine
[D] Sodium
Show Answer
Correct Answer: A [Calcium]
Notes:
The human body requires more calcium than any other mineral. At least 99% of the calcium is found in the bones and teeth, giving them strength and rigidity.
48. Alfalfa is the name of a kind of _____:
[A] Forest
[B] Crop
[C] Grass
[D] None of the above
Show Answer
Correct Answer: B [Crop]
Notes:
Alfalfa is a small seeded crop, and has a slowly growing seedling, but after several months of establishment, forms a tough ‘crown’ at the top of the root system. This crown contains many shoot buds that enables alfalfa to re-grow many times after being grazed or harvested. Alfalfa is widely grown throughout the world as forage for cattle.
49. Compounds that are needed for enzymes to function properly are
_____:
[A] Steroids
[B] Vitamins
[C] Heavy metals
[D] Buffers
Show Answer
Correct Answer: B [Vitamins]
Notes:
Vitamins are organic molecules that function in a wide variety of capacities within the body. The most prominent function of the vitamins is to serve as cofactors (co-enzymes) for enzymatic reactions. If an enzyme lacks the essential vitamin, it cannot perform its catalytic function properly.
50. Which of the following is true for photoperiodic?
[A] It occurs only in plants
[B] It is related to flowering in plants
[C] It is related to feathers of animals
[D] It is the reaction of organisms to the length of day or night
Show Answer
Correct Answer: D [It is the reaction of organisms to the length of day or night]
Notes:
Photoperiodism is the physiological reaction of organisms to the length of day or night. The term “Photoperiodism” was coined to describe a plant’s ability to flower in response to changes in the photoperiod: the relative lengths of day and night. Because flowers produce seeds, flowering is crucially important for the plant to complete its life cycle.
