11. Which of the following are the postulates of Darwin’s theory of evolution?
[A] Within any population, there is natural variation.
[B] Even though all species produce a large number of offsprings, populations remain fairly constant
[C] The struggle for survival within populations eliminates the unfit individuals.
[D] All the above are correct
Show Answer
Correct Answer: D [All the above are correct]
Notes:
Darwin’s theory of evolution can be described as: within any population, there is natural variation. Some individuals have more favourable variations than others. Even though all species produce a large number of offsprings, populations remain fairly constant naturally. The struggle for survival within populations eliminates the unfit individuals. This is called natural selection.
12. What is the name of a group of similar cells performing a specific function?
[A] Tissue
[B] Organ
[C] Organ system
[D] Cellular organization
Show Answer
Correct Answer: A [Tissue]
Notes:
A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.
13. Which of the following disease is non-communicable in nature?
[A] Tuberculosis
[B] Chicken-pox
[C] Cholera
[D] Cancer
Show Answer
Correct Answer: D [Cancer]
Notes:
A noncommunicable disease (NCD) is a medical condition or disease that is by definition non-infectious and non-transmissible among people. Eg. Cancer which is also called malignancy, is an abnormal growth of cells.
14. How the body temperature is maintained?
[A] Due to temperature regulating mechanism located in the base of the brain
[B] Due to excessive intake of water
[C] Due to regular intake of foods
[D] Due to the constant flow of blood in the capillaries
Show Answer
Correct Answer: A [Due to temperature regulating mechanism located in the base of the brain]
Notes:
The hypothalamus part of the brain works with other parts of the body’s temperature-regulating system, such as the skin, sweat glands and blood vessels. Water evaporating from the skin cools the body, keeping its temperature in a healthy range.
15. Mitochondrial DNA in an individual comes from which of the following sources? (UPSC Prelims 1991)
[A] Male parent
[B] Female parent
[C] Both parents
[D] Neither of the parents
Show Answer
Correct Answer: C [Both parents]
Notes:
Mitochondrial DNA is the small circular chromosome found inside mitochondria. The mitochondria, and thus mitochondrial DNA, are passed almost exclusively from mother to offspring through the egg cell. Electron microscopy reveals mitochondrial DNA in discrete foci.
16. Which of the following contain a protein named Alpha-keratin? (UPSC Prelims 1997)
[A] Blood
[B] skin
[C] wool
[D] eggs
Show Answer
Correct Answer: B [skin]
Notes:
Alpha-keratin, or α-keratin, is a type of keratin found in vertebrates. This protein is the primary component in hair, horns, mammalian claws, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure.
17. Which of the following is the name given to the cellular and molecular control of programmed cell death? (UPSC Prelims 2001)
[A] Apoptosis
[B] Ageing
[C] Degeneration
[D] Necrosis
Show Answer
Correct Answer: A [Apoptosis]
Notes:
• Apoptosis is the process of programmed cell death in multicellular organisms. Apoptosis occurs during normal cell turnover, development and in immune system.
• Ageing is the accumulation of changes.
• Degeneration is the deterioration of a tissue or an organ in which its function is diminished or its structure impaired.
• Necrosis is the disorganized break down of flesh in some part of the body of multicellular organism.
18. Which among the following are female sex harmones?
[A] Estrogen
[B] Progesterone
[C] Testosterone
[D] Both a and b
Show Answer
Correct Answer: D [Both a and b]
Notes:
Estrogen and progesterone are the female sex harmones. Estrogen is responsible for the development of secondary sexual characteristics. Progesterone supports during pregnancy and controls the menstrual cycles in women.
19. Which among the following types of bees does not have commercial importance?
[A] Dammer bee
[B] The little bee
[C] The Indian hive bee
[D] None of the above
Show Answer
Correct Answer: D [None of the above]
Notes:
There are around 20,000 different species of bees in the world but only 7 of them are honeybees. Of them only five of them have commercial importance in India, they are as follows:
1. The rock bee
2. The Indian hive bee
3. The little bee
4. The European bee
5. Dammer bee
20. Robert Hooke is known for which of the following works?
[A] how messages pass between nerve cells in mammals
[B] first use of the word cell
[C] theory of punctuated equilibrium
[D] aquatic ape theory
Show Answer
Correct Answer: B [first use of the word cell]
Notes:
Robert Hooke is known for his discovery of the law of elasticity (Hooke’s law), for his first use of the word cell in the sense of a basic unit of organisms, and for his studies of microscopic fossils, which made him an early proponent of a theory of evolution.
