11. Corpus luteum is a mass of cells found in which organ? (UPSC Prelims 1997)
[A] brain
[B] ovary
[C] pancreas
[D] spleen
Show Answer
Correct Answer: B [ovary]
Notes:
The corpus luteum is a hormone-secreting structure that forms in the ovary after an egg has been released during ovulation. It is made up of cells that were part of the follicle that contained the egg, and it produces the hormones progesterone and estrogen, which help to support pregnancy. The corpus luteum is important for maintaining the lining of the uterus and preparing the body for pregnancy. If pregnancy does not occur, the corpus luteum will break down and be absorbed by the body.
12. At which stage in its life-cycle does the silkworm yield the fibre of commerce? (UPSC Prelims 2000)
[A] Egg
[B] Larva
[C] Pupa
[D] Imago
Show Answer
Correct Answer: C [Pupa]
Notes:
Silk worm yield the fibre from pupa stage, which is commercially used to produce clothes.
13. “Athlete’s Foot” is a disease caused by which of the following microorganisms? (UPSC Prelims 2001)
[A] Bacteria
[B] Fungus
[C] Protozoan
[D] Nematode
Show Answer
Correct Answer: B [Fungus]
Notes:
It is a member of the group of diseases known as tinea. Athlete’s foot is caused by a number of different fungi, including species of Trichophyton, Epidermophyton, and Microsporum. The condition is typically acquired by coming into contact with infected skin, or fungus in the environment.
14. Which among the following is not a bio-fertilizer?
[A] Vermi compost
[B] Urea
[C] Azobacter
[D] Clostridium
Show Answer
Correct Answer: B [Urea]
Notes:
Biofertilizers are substances that contain microorganisms, which when added to the soil increase its fertility and promote plant growth. Urea is not a biofertilizer.
15. Which of the following branch of biology deals with the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants?
[A] Agriforestry
[B] Horticulture
[C] Arboriculture
[D] Forestry
Show Answer
Correct Answer: C [Arboriculture]
Notes:
Arboriculture is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants.
16. Study of the chemical nature of cells and tissues is known as__?
[A] Biochemistry
[B] Conchology
[C] Histochemistry
[D] Dermatology
Show Answer
Correct Answer: C [Histochemistry]
Notes:
Histochemistry combines the techniques of biochemistry and histology in the study of the chemical constitution of cells and tissues.
17. Who among the following is considered as the father of modern ecology?
[A] Ramdeo Misra
[B] Parthasarthy Iyengar
[C] Eugene Odum
[D] Theophrastus
Show Answer
Correct Answer: C [Eugene Odum]
Notes:
Eugene Odom is known throughout science as the father of modern ecology.
18. Which of the following biomolecules is more widely distributed in the cell?
[A] Chloroplast
[B] RNA
[C] DNA
[D] Spaherosomes
Show Answer
Correct Answer: B [RNA]
Notes:
DNA and RNA are two types of nucleic acids. DNA is converted into RNA by the process of transcription. The three types of RNA are m-RNA, t-RNA and r-RNA.
19. Which of the following virus is covered?
[A] Adeno
[B] Herpes
[C] Polio
[D] None of these
Show Answer
Correct Answer: B [Herpes]
Notes:
The Herpesviridae are a large family of DNA viruses. It causes infections and some diseases in animals, including humans. Members of this family are also known as herpesviruses.
20. Which of the following is not a characteristic of gymnosperms?
[A] Parallel venation
[B] Perennial plants
[C] Distinct branches
[D] Xylem with vessels
Show Answer
Correct Answer: D [Xylem with vessels]
Notes:
The characteristics of gymnosperms: They do not produce flowers, Seeds are not formed inside a fruit, they are found in colder regions where snowfall occurs, they develop needle-like leaves, they are perennial or woody, forming trees or bushes, they are not differentiated into the ovary, style, and stigma.
