Control and Co-ordination — BIOLOGY STD 12 Science — Question

Distinguish between : Epithalamus and hypothalamus.

Read the following and answer any four questions from (i) to (v) given below:
A desert lizard (an ectotherm) and a mouse (an endotherm) are placed inside a chamber at 15ºC and their body temperature [T(L) for the lizard and T(M) for the mouse] and metabolic rates [M(L) for lizard and M(M) for the mouse] are monitored.

1. Which of the following is correct regardingT(L), M(L), T(M) and M(M)?

1. T(L) and M(L) will fall while T(M) and M(M) will increase.
2. T(L) and M(L) will increase while T(M) and M(M) will fall.
3. T(L) and M(L) will fall, T(M) will remain same and M(M) will increase.
4. T(L) and M(L) will remain same, T(M) and M(M) will decrease.

2. It can be said that some animals in their evolutionary development preferred to be ectotherms than endotherms. Which of the following can be the best suited reason for it?

1. The metabolic reactions of these organisms can occur at a very wide range of temperature.
2. Maintaining homeostasis is an energetically expensive process.
3. The enzymes of these organisms are functional at high temperatures.
4. Both (b) and (c).

3. Organisms that can maintain a constant internal temperature are called.

1. Homoeothermic
2. Poikilothermic
3. Oligothennic
4. Heterothennic

4. An animal that survives at temperature of 10ºC and 40ºC both can be placed under the category of:

1. Ectotherm.
2. Endotherm.
3. Modifiers.
4. Migratory organisms.

5. Study the graph carefully and select the correct option.

1. X could be desert lizard.
2. Y could be mouse.
3. Z could be desert lizard.
4. Both (a) and (b).

Read the following and answer any four questions from (i) to (v) given below:
Wetlands are called Ramsar sites because the first international convention on their conservation was held in Ramsar in Iran in 1971. Wetlands or Ramsar sites are low lying marshy areas which get filled up during rains due to runoff and overflow from other water bodies. They are often considered to be waste lands which are used as dumping areas and filled up to recover land for various constructions activities. As a result, a large number of wetlands have disappeared.

1. Select the incorrect match of wetland and its location.

	Wetland	Location
(a)	Harike	Punjab
(b)	Chandra Tai	H.P.
(c)	Bhoj	M.P.
(d)	Ashtamudi	Odisha

2. Migratory bird flamingo breeds in which of the following wetlands?

1. Bhitarkanika Mangroves.
2. Rann of Kutch.
3. Harike.
4. Chandra Tal.

3. Which of the following is not an importance of wetlands?

1. They are an important source of recharging groundwater.
2. They provide protection from floods.
3. They are good source of siltation and purification of water.
4. None of these.

4. Which of the following wetland ecosystem is highly acidic and has a accumulation of decomposed plants known as peat?

1. Bog
2. Mangrove
3. Estuary
4. Watershed

5. The mangroves of Bhitarkanika are famous for:

1. Rare migratory waterbirds.
2. Nesting sites for endangered olive ridley turtles.
3. Prawn cultivation.
4. All of these.

Read the following and answer any four questions from (i) to (v) given below:
During copulation, semen is released by the penis into the vagina. 'The motile sperms swim rapidly, fuse with ovum in the ampullary region, resulting in fertilisation. Haploid nucleus of sperm fuse with that of ovum to form diploid zygote.

1. In female genital tract, sperms are made capable of fertilising the egg. This phenomenon of sperm activation is called:

1. Amphimixis.
2. Cortical reaction.
3. Capacitation.
4. Acrosomal reaction.

2. Select the correct sequence of various physical and chemical events that take place during fertilisation.

16. Fusion of cortical granules with plasma membrane of secondary oocyte.
17. Formation of fertilisation cone to receive sperm.
18. Release of sperm lysin from acrosome.
19. Mixing up of chromosomes of a sperm and an ovum.

1. R → Q → P → S
2. Q → S → R → P
3. Q → R → S → P
4. R → P → Q → S

3. Assertion: Only one sperm can fertilise an ovum.

Reason: The secretion of acrosome help the sperm to enter into cytoplasm of ovum through zona pellucida and plasma membrane.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. Both assertion and reason are false

4. What is the significance of fertilisation?

1. It restores haploid number of chromosomes.
2. It produces offspring genetically identical to parents.
3. It initiates cleavage.
4. Both (b) and (c).

5. Site of fertilisation in humans is:

1. Endometrium of uterine cavity.
2. Ampullary isthmic junction of oviduct.
3. Cervix of uterus.
4. Infundibulum of fallopian tube.

Distinguish between : Cranial nerves and Spinal nerves

Read the following and answer any four questions from (i) to (v) given below:
A functional mammary gland is characteristic of all female mammals. Mammary glands are paired structures that contain glandular tissue and variable amount of fat. Refer to the given figure of a mammary gland and answer the following questions.

1. Mammary glands are modified:

1. Sweat glands.
2. Sebaceous glands.
3. Sudoriferous glands.
4. Lacrimal glands.

2. Identify the incorrectly matched pair.

1. P - Areola.
2. Q - Lactiferous duct.
3. S - Mammary duct.
4. T - Mammary alveoli.

3. Mammary ducts expand to form:

1. Mammary alveoli.
2. Mammary ampullae.
3. Lactiferous ducts.
4. Mammary tubules.

4. What is areola?

1. Grape-like clusters of milk secreting structures.
2. Fatty tissue between the mammary lobes.
3. Circular pigmented area of skin around nipple.
4. Connective tissue that supports the alveoli and ducts.

5. Assertion: The size of breast depends on the amount of adipose tissue.

Reason: The adipose tissue supports the alveoli and the ducts.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. Both assertion and reason are false.

Read the following and answer any four questions from (i) to (v) given below:
Biosphere reserves are multipurpose protected areas which are meant for preserving genetic diversity in representative ecosystems of various natural biomes and unique biological communities by protecting wild populations, traditional life style of tribals and domesticated plant/animal genetic resources. Each biosphere reserve has three zones-core, buffer and transition zone.

1. Which of the following is similar to biosphere reserve in terms of conservation?

1. Gene banks.
2. Offsite collection.
3. Orchards.
4. Hotspots.

2. Refer to the given figure representing different zones of a biosphere reserve and select the correct option regarding it.

1. A-Limited human activity is allowed such as for research and education.
2. B-An active co-operation occurs between reserve management and local people for activities like cropping, settlements, etc.
3. C-No human activity is allowed.
4. None of these.

3. Refer to the given diagrammatic representation of a biosphere reserve.

Select the incorrect statement regarding X, Y and Z.

1. X is devoted to strict protection of wildlife and no human activity is allowed in this zone.
2. In Y, only limited human activity (compatible with conservation) is allowed.
3. In Z, commercial exploitation of natural resources is allowed.
4. Tourism is allowed in Z zone only.
5. Zone Y helps to maintain the lifestyle of the tribal people living in the area.

1. (iii), (iv) and (v) only
2. (ii), (iii) and (v) only
3. (i), (iii) and (iv) only
4. (ii), (iii) and (iv) only

4. Biosphere reserves differ from national parks and wildlife sanctuaries because in the former.

1. Human beings are not allowed to enter
2. People are an integral part of the system
3. Plants are paid greater attention than the animals
4. Living organisms are brought from all over the world and preserved for posterity.

5. MAB Programme means.

1. Man and biosphere programme.
2. Man and biodiversity conservation programme.
3. Manually aided biosphere conservation programme.
4. None of these.

Callus culture and Suspension culture.