Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

1. What are the three options that can be thought of, to increase food production?
2. Mention the reasons for the success of Green Revolution in increasing food production.
3. Why do we still search for other alternatives to increase food production?

1. What is the significance of offsite collections?

1. Restock depleted populations.
2. Protection of endangered species.
3. Reintroduce species in wild.
4. All of these.

2. Which of the following is not an ex-situ conservation?

1. Wetlands
2. Orchards
3. Aquaria
4. Botanical gardens.

3. Select the incorrect statements for ex-situ conservation.

1. It is conservation of species outside their natural habitats.
2. Endangered species are kept under human supervision and provided all the essentials.
3. The species population recovers in natural environment.
4. Both (b) and (c).

4. Conditions maintained in seed banks for orthodox seeds are:

1. Low moisture content.
2. Anaerobic conditions.
3. Low temperature.
4. All of these.

5. Assertion: Animal species which have become extinct in wild continue to be maintained in zoological parks.

Reason: Captive breeding is the conservation of those cases where these is no realistic chance of in-situ survival.

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.

1. Which method helps in contraception by temporary absence of sex?

1. Coitus interruptus.
2. Withdrawal method.
3. Rhythm method.
4. Lactational amenorrhea method.

2. Assertion: The effectiveness of coitus interruptus method is limited.

Reason: Some sperms may pass into vagina before ejaculation.

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.

3. Why is lactational amenorrhea effective for about 4-5 months after parturition?

1. Ovulation occurs on about the 14^th day of menstruation.
2. Ovulation does not occur during intense lactation.
3. This method inhibits mobility of sperms.
4. Both (b) and (c).

4. Which fact is not the basis of periodic absence method of birth control?

1. Ovum remains alive for about 1-2 days.
2. Ovulation occurs on about 14^th day of menstruation.
3. Sperms survive for about 3 days.
4. Alteration in uterine endometrium.

5. On which days of menstrual cycle should coitus be avoided to prevent fertilisation?

1. 10-17
2. 6-13
3. 1-5
4. 15-28

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

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.

1. True embryo develops as a result of fusion of:

1. Two polar nuclei of embryo sac.
2. An egg cell and a male gamete.
3. Synergid and male gamete.
4. A male gamete and antipodals.

2. Refer to the given diagram of the embryo of an angiospermous plant with parts labelled P, Q and R. Select the correct statement(s) regarding this.

1. Part 'P' supplies nutrition to the developing embryo.
2. Part 'Q' is the protective sheath of radicle and root cap.
3. Part 'R' is the protective sheath of shoot apex and leaf primordia.
4. The embryo shown in the diagram is present in members of Family Poaceae.

1. (IV) only.
2. (II) and (III) only.
3. (I) and (IV) only.
4. (I), (II), (III) and (IV).

3. Which of the given statements are true?

1. During the development of a dicot embryo, heart-shaped embryo is followed by globular embryo.
2. The part of embryonal axis above the level of cotyledons is epicotyl, while the part below the level of cotyledons is hypocotyl.
3. Monocot seeds possess a single cotyledon, represented by scutellum.

1. (I) and (II).
2. (II) and (III).
3. (I) and (III).
4. (I), (II) and (III).

4. Consider the following parts of an embryonal axis of a dicot seed.

1. Hypocotyl.
2. Epicotyl.
3. Radicle.
4. Plumule.

In which of the following the above parts are correctly arranged from top to base?

1. (III) → (I) → (II) → (IV).
2. (II) → (I) → (III) → (IV).
3. (IV) → (II) → (I) → (III).
4. (III) → (IV) → (II) → (I).

5. In grass family, the cotyledon, is called:

1. Epiblast.
2. Plumule.
3. Scutellum.
4. Perisperm.

1. Identify W, X, Y and Z.

2. Select the correct statement.

1. If X is sleeping sickness then its vector is Leishrnania.
2. If Y is diphtheria then it is caused by Bacillus anthracis.
3. If W is hypothyroidism then it is caused by deficiency of thyroxine hormone.
4. If Z is myocardial infarction then patient develops acute rheumatic fever, joint pain and throat infection.

3. If X and Y both are usual diseases then which of the following holds true?

1. X could be dengue caused by flavivirus and Y could be AIDS caused by HIV.
2. X could be chikungunya whereas Y could be rhinitis.
3. X could be hepatitis whereas Y could be rabies.
4. X could be chicken pox caused by Va rice/la zoster virus whereas Y could be yellow fever caused by flavivirus

4. If X and Y both are bacterial diseases then select the correct match from the following.

1. X- Bubonic plague-Yersinia pestis
2. Y-Leprosy- Mycobacteriurn leprae
3. X-Whooping cough-Bordetella pertussis
4. Y-Botulism-Clostridiurn botulinum

5. Assertion: Communicable diseases could be contagious or non-contagious.

Reason: Diseases that spread through vectors are non-contagious 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.