11. Which of the following defines an Antigen? (UPSC Prelims 2001)
[A] destroys harmful bacteria
[B] is used to treat poisoning
[C] lowers body-temperature
[D] stimulates formation of antibody
Show Answer
Correct Answer: D [stimulates formation of antibody]
Notes:
An antigen is any substance that causes your immune system to produce antibodies against it. An antigen may be a substance from the environment, such as chemicals, bacteria, viruses, or pollen. An antigen may also form inside the body.
12. Lepidopterology is a branch of biology, which deals with the studies of which of the following?
[A] Lipids and fats
[B] Butterflies and moths
[C] Tongue
[D] Lakes and Ponds
Show Answer
Correct Answer: B [Butterflies and moths]
Notes:
Lepidopterology is a branch of entomology that deals with the scientific study of moths and three superfamilies of butterflies.
13. Empedocles is related to which of the following theory of biology?
[A] theory of cell
[B] theory of natural selection
[C] theory of mutation
[D] theory of disease
Show Answer
Correct Answer: B [theory of natural selection]
Notes:
Empedocles formulated a theory of natural selection. He proposed that everything in existence is composed of different combinations of four elements: air, fire, water and earth.
14. What is Rancidity?
[A] Deterioration of Fat
[B] Deterioration of Glucose
[C] Deterioration of Protein
[D] Deterioration of Vitamins
Show Answer
Correct Answer: A [Deterioration of Fat]
Notes:
The process of oxidation of oily and Fatty food, which changes its taste and smell is known as Rancidity. Rancidity generally occurs in Fat.
15. Enzyme neuraminidase is carried by which of the following virus?
[A] Human immunodeficiency virus
[B] Epstein-Barr virus
[C] Influenza virus
[D] Adenovirus
Show Answer
Correct Answer: C [Influenza virus]
Notes:
Viral neuraminidase is a type of neuraminidase found on the surface of the influenza virus that enables the virus to be released from the host cell. Neuraminidases are enzymes that dissociate sialic acid groups from glycoproteins.
16. In bryophytes and pteridophytes, male gametes are transported through which of the following?
[A] Air
[B] Water
[C] Birds
[D] Insects
Show Answer
Correct Answer: B [Water]
Notes:
In plants, water acts as the channel through which gamete transfer takes place.
17. Cooci which are mostly single or in pairs are called?
[A] Streptococci
[B] Diplococci
[C] Tetracocci
[D] None of these
Show Answer
Correct Answer: B [Diplococci]
Notes:
A diplococcus is a round bacterium (a coccus). It usually occurs as two joined cells.
18. Which of the following is a calyx?
[A] the second whorl of a flower
[B] the third whorl of the flower
[C] the outermost whorl of a flower
[D] None of these
Show Answer
Correct Answer: C [the outermost whorl of a flower]
Notes:
The calyx is the outermost whorl of a flower, consisting of sepals, small leaves present at the base of the flower. These protect the flowering clump against mechanical injury and drying. The calyx in some plants is colored sepals called petaloid.
19. Which of the following provides structural support to the plant?
[A] lignin
[B] companion cells
[C] Sclerenchyma
[D] sieve tubes
Show Answer
Correct Answer: A [lignin]
Notes:
Xylem fibers and tracheids are composed of lignin, and this provides structural support to the plant.
20. On which of the following factor rates of photosynthesis depends?
[A] pH
[B] Pressure
[C] Intensity of Light
[D] Amount of reactance
Show Answer
Correct Answer: C [Intensity of Light]
Notes:
The rate of photosynthesis mainly depends on the Intensity of Light, carbon dioxide concentration, and temperature.