Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

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).

Give a detailed description of human male reproductive system. (Diagram required)

Read the following and answer any four questions from (i) to (v) given below:

Reerna, Jai and Ankit are suffering from autoimmune diseases of adrenal cortex, joints and thyroid gland, respectively. Their immune system failed to recognise self and non-self and started destroying their body's own proteins. They are seeking proper medical help for their conditions but their condition cannot be cured completely.

Based on the above information, answer the following questions.

1. Select the option that correctly identifies autoimmune diseases of Reema, Jai and Ankit.

S no.	Reema	Jai	Ankit
(a)	Diabetes	Grave's disease	Rheumatic fever
(b)	Pernicious anaemia	Multiple sclerosis	Myasthenia gravis
(c)	Addison's disease	Rheumatoid arthritis	Hashismoto's thyroiditis
(d)	Systemic lupus erythematosus	Severe combined immunodeficiency disease	AIDS

2. Reema's autoimmune condition is characterised by

1. Undersecretion of insulin.
2. Destruction of RB Cs and low RB C count.
3. Undersecretion of adrenal cortex hormones.
4. Low production of intrinsic factor required for absorption of B₁₂

3. What do you think is the major cause of Jai's condition?

1. Deterioration of myelin sheath around nerve cells, leading to loss of precise muscle control
2. Destruction of heart cells, leading to weakening of entire heart wall.
3. Destruction of beta cells, leading to undersecretion of insulin.
4. Deposition of immune complexes of IgM, IgG and complement in joints thereby inflaming joints, destroying articular cartilage and fusing bones.

4. How do you think Ankit's condition got diagnosed?

1. Low level of thyroid hormone and elevated levels of TSH in Ankit's blood.
2. Presence of antibodies against thyroid pen oxidase (TPO antibodies) in Ankit's blood.
3. Elevated erythrocyte sedimentation rate (ESR), reduced C-reactive protein (CRP) in Ankit.
4. Both (a) and (b)

5. Assertion: Immunosuppressive drugs often reduce the severity of autoimmune disorders.

Reason: Monoclonal antibodies have been successfully used in the treatment of autoimmune disease.

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.

Describe tissue culture.

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.

Explain population attributes.

Read the following text carefully and answer the questions that follow:
After implantation, finger-like projections appear on the trophoblast called chorionic villi which are surrounded by the uterine tissue and maternal blood. The chorionic villi and uterine tissue become interdigitated with each other and jointly form a structural and functional unit between the developing embryo (foetus) and the maternal body.

i. Name the hormone crucial in parturition. Does the parturition signal originate from the mother or the fetus?(1)
ii. When and where do chorionic villi appear in humans? (1)
iii. Woman has conceived and implantation has occurred. Discuss the impact of progesterone and estrogen. (2)
OR
Fetal ejection reflex leads to parturition. Justify (2)

Read the following and answer any four questions from (i) to (v) given below:

Oogenesis is the process of formation of ovum in ovaries. It consists of three phases : multiplication, growth and maturation. Oogenesis is controlled by hormones GnRH, LH, FSH. GnRH secreted by the hypothalamus stimulates the anterior lobe of pituitary gland to secrete LH and FSH.

1. What is the function of hormone FSH?

1. It inhibits the formation of estrogen.
2. It induces the release of secondary oocyte.
3. It stimulates the growth of Graafian follicles.
4. It causes ovulation.

2. Which hormone induces the rupture of the mature Graafian follicle?

1. Follicle stimulating hormone.
2. Gonadotropin releasing hormone.
3. Progesterone.
4. Luteinising hormone.

3. Which cell division is involved in the formation of secondary oocyte?

1. Mitosis.
2. Meiosis I.
3. Amitosis.
4. Meiosis II.

4. Identify the function(s) of LH.

1. Release of secondary oocyte from Graafian follicle.
2. Stimulates corpus luteum to secrete progesterone.
3. Stimulates estrogen formation.
4. Promotes development of egg to form secondary oocyte.

1. (A) and (B) only.
2. (B) and (C) only.
3. (A), (C) and (D) only.
4. (B) only.

5. Assertion: The increase in progesterone level exerts positive feedback on GnRH.

Reason: The rising level of progesterone stimulate production of FSH and LH.

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:
In angiosperms, the pollen grains are being transferred from the anther to the stigma and is termed pollination. This phenomenon was first discovered by Camerarius (1694) in the end of seventeenth century. Pollen grains are immobile. They cannot reach the stigma by themselves. An external agent is required for this. The pollination is mainly of two types-self pollination and cross pollination. The diagram given below shows two plants of the same species showing different types of pollination.

1. What is transferred between the plants in the process indicated by arrow P?

1. Ova.
2. Pollen.
3. Nutrients.
4. Seeds.

2. Which of the following statements is correct regarding processes P, Q and R?

1. Processes P, Q and R introduce genetic variability in the offspring of sexually reproducing plants X and Y.
2. Wind serves as agent for process Q if plants X and Y belong to Genus Salvia.
3. Flowers of plants X and Y need to produce odour and nectar for completion of processes P and Q if they are entomophilous.
4. If plants X and Y belong to Genus Cannabis, then their flowers need to produce sticky and heavy pollens in very small amount for accomplishment of process Q.

3. Identify the processes P, Q and R.

S. No	P	Q	R
(a)	Geitonogamy	Xenogamy	Autogamy
(b)	Allogamy	Chasmogamy	Cleistogamy
(c)	Autogamy	Geitonogamy	Xenogamy
(d)	Geitonogamy	Allogamy	Autogamy

4. In Catliarantl1us, the growth of style brings the stigma in contact of ripe anthers present on the mouth of corolla tube. This is an example of:

1. Homogamy.
2. Cleistogamy.
3. Geitonogamy.
4. Xenogamy.

5. Which of the given processes represents a type of pollination that would result in greater adaptability of the particular species to potential environmental changes?

1. P.
2. Q.
3. R.
4. All of these.