11. Which of the following is the process through which plants reproduce?
[A] Condensation
[B] Evaporation
[C] Pollination
[D] Eating
Show Answer
Correct Answer: C [ Pollination ]
Notes:
Sexual reproduction in flowering plants involves the production of male and female gametes, the transfer of the male gametes to the female ovules in a process called pollination. After pollination occurs, fertilization happens and the ovules grow into seeds within a fruit.
12. Consider the following statements regarding bones in the human body:
- They consist of 80% solid matter and20% water.
- Solid matter in the bones is made mainly of cartilage.
- Impregnation of salts including carbonates and phosphates of lime imparts hardness to the bones.
- In old age, the proportion of lime decreases and bones become brittle and break easily.
Of these statements:
[A] 1,2 and 3 are correct
[B] 2 and 4 are correct
[C] 2 and 3 are correct
[D] 1, 2, 3 and 4 are correct
Show Answer
Correct Answer: D [1, 2, 3 and 4 are correct]
Notes:
All of them are correct.
Bones consist of living cells embedded in a mineralized organic matrix. This matrix consists of organic components, mainly type I collagen – “organic” referring to materials produced as a result of the human body – and inorganic components, primarily hydroxyapatite and other salts of calcium and phosphate.
13. Which pigment is responsible for the colour of healthy skin in human beings?
[A] Bilirubin
[B] Haemoglobin
[C] Melanin
[D] Progesterone
Show Answer
Correct Answer: C [Melanin]
Notes:
The single most factor responsible for the cpolour of the skin is the pigment melanin. It is secreted by the melanocytes within the skin.
14. Which part of the human body is affected by Alziemer’s disease?
[A] Brain
[B] Lungs
[C] Heart
[D] Kidneys
Show Answer
Correct Answer: A [Brain]
Notes:
Alziemer’s is a disease which attacks the neural system, It results in continuous decline in the number brain cells which leads to loss of memory.
15. Which of the following is the subject matter of genetics?
[A] Forms and features of plant parts
[B] Heredity and variations
[C] the disorder of living beings
[D] None of these
Show Answer
Correct Answer: B [Heredity and variations]
Notes:
Genetics is the study of heredity in general and genes in particular. Genetics is one of the central pillars of biology and overlaps with many other fields such as agriculture, medicine and biotechnology.
16. What is an enzyme?
[A] Acid
[B] Base
[C] Salt
[D] Catalyst
Show Answer
Correct Answer: D [Catalyst]
Notes:
Enzyme is a protein. It acts as a catalyst in living organisms, and controls the rate of chemical reactions inside the body.
17. Which of the following pigments gives the yellow colour to leaves, fruits and flowers?
[A] Chlorophyll
[B] Haemoglobin
[C] Anthocyanin
[D] Xanthophyll
Show Answer
Correct Answer: D [Xanthophyll]
Notes:
Xanthophyll is the pigment that provides yellow color to leaves, fruits, and flowers. Here Xanthos stands for yellow, phyllon means leaf.
18. Which of the following also play a role in protecting plants against bacterial and fungal infections?
[A] Jasmonates
[B] Oligosaccharins
[C] Strigolactones
[D] Brassinosteroids
Show Answer
Correct Answer: B [Oligosaccharins]
Notes:
Oligosaccharides also play a role in protecting plants against bacterial and fungal infections. They act locally at the site of injury. They can also be carried to other tissues.
19. The loss of tail in reptiles is called?
[A] bipedalism
[B] fangs
[C] autotomy
[D] panting
Show Answer
Correct Answer: C [autotomy]
Notes:
The loss of the tail in reptiles is called autotomy. Autotomy or self-mutilation is the behavior by which an animal sheds or discards one or more of its own appendages
20. Consider the following:
- Candle
- Linoleum
- Shoe cream
- Cellophane
Which of the above are made from animal fat?
[A] Only 1 and 2
[B] Only 2 and 3
[C] Only 2, 3 and 4
[D] 1, 2, 3 and 4
Show Answer
Correct Answer: D [1, 2, 3 and 4]
Notes:Various animal by-products are produced from fats. These include
- Candles: Traditionally, animal fat, particularly tallow, was used to make candles before the development of more modern materials.
- Linoleum: Linseed oil is a primary ingredient in genuine linoleum, and it is sometimes mixed with other oils like castor oil, that derive from animal fats.
- Shoe cream: Shoe creams and polishes regularly use animal fats to help condition and soften the leather.
- Cellophane: Cellophane isn’t made directly from animal fat, but its production includes the use of glycerol, which can be derived from animal fats.