11. Which of the following are chlorophyll-bearing, simple, thalloid, autotrophic and largely acquatic(both fresh water and marine) organisms?
[A] Gymnosperms
[B] Bryophytes
[C] Pteridophytes
[D] Algae
Show Answer
Correct Answer: D [Algae]
Notes:
Algae is an informal term for a large, diverse group of photosynthetic eukaryotic organisms that are not necessarily closely related, and is thus polyphyletic.
12. Why honey bees are called social insects? (UPSC Prelims 1982)
[A] They visit all flowers to collect nectar
[B] They live in large family groups
[C] They depend for their food upon other insects
[D] They move socially with other insects
Show Answer
Correct Answer: B [They live in large family groups]
Notes:
Social insects are highly evolved insects that engage in a variety of complex tasks not practiced by the multitude of solitary insects. Honey bees are social insects because they live together in large, well-organized family groups. A single honeybee cannot grow or survive by itself. The three distinct kinds of honeybees in a colony are queen, worker, and drone.
13. The saliva helps in the digestion of which of the following materials? (UPSC Prelims 1988)
[A] Starch
[B] Proteins
[C] Fibers
[D] Fats
Show Answer
Correct Answer: A [Starch]
Notes:
The digestive functions of saliva include moistening food, and helping to create a food bolus, so it can be swallowed easily. Saliva contains the enzyme amylase that breaks some starches down into maltose and dextrin. Thus, digestion of food occurs within the mouth, even before food reaches the stomach.
14. When one gene controls two or more different characters simultaneously, the phenomenon is known by which of the following names? (UPSC Prelims 2002)
[A] Apomixis
[B] Pleiotropy
[C] Polyploidy
[D] Polyteny
Show Answer
Correct Answer: B [Pleiotropy]
Notes:
• Polyploidy occurs in cells and organisms when there are more than two paired (homologous) set of chromosome founds which controls more than one characters simultaneously.
• Apomixis is the process of asexual reproduction in which the embryo grows from egg cells without being fertilized.
• Pleiotropy occurs when a single gene influences multiple phenotypic traits.
• Polytene is a giant chromosome found in some two-winged flies.
15. Which vitamin deficiency leads to the disease rickets?
[A] Vitamin A
[B] Vitamin C
[C] Vitamin D
[D] Vitamin K
Show Answer
Correct Answer: C [Vitamin D]
Notes:
Rickets is a disease related to bone disorder due to the deficiency of vitamin D. Vitamin D is a fat soluble vitamin. Vitamin D is also called as calciferol. Lack of calcium also leads to rickets.
16. Which gland acts as thermostat of human body?
[A] Pancreas
[B] Pituitary
[C] Thyroid
[D] Hypothalamus
Show Answer
Correct Answer: D [Hypothalamus]
Notes:
Hypothalamus acts as the thermostat of human body as it regulates the body temperature as the same way a thermostat controls the room temperature. It is located in the skull of the human body.
17. What was “Albert Szent-Gyorgyi” famous for?
[A] As a Hungarian biochemist
[B] As a Hungarian physicist
[C] As a Hungarian mathematician
[D] As a Hungarian novelist
Show Answer
Correct Answer: A [As a Hungarian biochemist ]
Notes:
Albert Szent-Gyorgyi was a Hungarian biochemist who won the Nobel Prize in Physiology or Medicine in 1937. He is credited with first isolating vitamin C and discovering the components and reactions of the citric acid cycle. He was also active in the Hungarian Resistance during World War II and entered Hungarian politics after the war.
18. The science of histology is related to which of the following studies?
[A] Tissues
[B] Cells
[C] Algae
[D] Fungi
Show Answer
Correct Answer: A [Tissues]
Notes:
Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissues.
19. Which statement is true for the capsid?
[A] It consists of capsomeres
[B] This the outermost layer of most viruses
[C] It protects genetic material
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
A capsid is the protein shell of a type of virus, which encloses its genetic material.
20. In which of the following cells are chloroplasts present?
[A] plants
[B] algae
[C] Both 1 & 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: C [Both 1 & 2]
Notes:
Chloroplasts are present in the cells of all green tissues of plants and algae. Chloroplasts are also found in photosynthetic tissues that do not appear green.
