11. Which of the following is the reason behind when one enters a dark room; he is not able to see anything but after some time his vision improves? (UPSC Prelims 1983)
[A] The retina of the eye comes forward
[B] The retina of the eye moves backward
[C] The pupil of the eye contracts
[D] The pupil of the eye dilates
Show Answer
Correct Answer: D [The pupil of the eye dilates]
Notes:
Our eyes cannot see everything clearly when we enter a dark room from a bright light. This is due to the reason that in dark room the pupil is large so when we come out in bright light, a large amount of light enters our eyes and we feel glare.
12. Which vitamin is also called as niacin?
[A] Vitamin C
[B] Vitamin B3
[C] Vitamin B12
[D] Vitamin B9
Show Answer
Correct Answer: B [Vitamin B3]
Notes:
Vitamin B3 is also called as niacin/Nicotinic acid with chemical formula C6H5NO2. Niacin is water soluble vitamin.
13. Which of the following statements are correct with respect to homeostasis?
1. Ecosystems are capable of maintaining their state of equilibrium.
2. They cannot regulate their own species structure and functional processes.
Select the correct option from the codes given below:
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 & 2
Show Answer
Correct Answer: A [Only 1]
Notes:
Ecosystems are capable of maintaining their own state of equilibrium. They can regulate their own species structure and functional processes. This capacity of ecosystem of self regulation is referred to as homeostasis.
14. Which branch of biology is known for the study of cells?
[A] Cytology
[B] Bacteriology
[C] Bryology
[D] Mycology
Show Answer
Correct Answer: A [Cytology]
Notes:
The study of cell or cell biology is called cytology. The initial phase of cytology began with the English scientist Robert Hooke’s microscopic examination of cork in 1665. He observed dead cork cells and introduced the word “cell” to describe them.
15. Which branch of biology is known for the study of fruits?
[A] Pomology
[B] Agronomy
[C] Floriculture
[D] None of these
Show Answer
Correct Answer: A [Pomology]
Notes:
Pomology is a branch of botany that studies fruit and its cultivation.
16. Mammology is the branch of science related to the study of?
[A] mammals
[B] breasts
[C] mollusks
[D] none of these
Show Answer
Correct Answer: A [mammals]
Notes:
Mammology is a branch of biology that deals with the study of mammals.
17. Serology is related to which of the following statements?
[A] Study of dietetics
[B] Study of snakes
[C] Study of serum
[D] Study of seeds
Show Answer
Correct Answer: C [Study of serum]
Notes:
Serology is the study of blood serum (the clear fluid that separates when blood clots).
18. Which of the following vitamins was crystallized by Harry Holmes and Ruth Corbet?
[A] Vitamin A
[B] Vitamin B
[C] Vitamin C
[D] Vitamin E
Show Answer
Correct Answer: A [Vitamin A]
Notes:
Harry Holmes and Ruth Corbet isolated and crystallized vitamin A in 1937. Vitamin A is important for normal vision, the immune system, and reproduction.
19. How do small molecules pass through the outer membrane of mitochondria?
[A] Carrier protein
[B] Channels
[C] Porins
[D] ATP pump
Show Answer
Correct Answer: C [Porins]
Notes:
The outer membrane is a relatively simple phospholipid bilayer made up of protein structures called porins. This makes it permeable to molecules of about 10 kilodaltons or less.
20. Which of the following includes ‘club fungus’ in this fungal division?
[A] Zygomycota
[B] Deuteromycota
[C] Basidiomycota
[D] Ascomycota
Show Answer
Correct Answer: C [Basidiomycota]
Notes:
Basidiomycota is one of the two larger divisions. Together with the Ascomycota, they constitute the subfamily Dicarya within the kingdom Fungi.