Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

Write a note Lac operon

Explain different types of RNA along with process of transcription.

Explain exponential growth equation with well labeled diagram.###Explain exponential growth.

Explain Methodology of HGP

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.

What is oogenesis? Give a brief account of oogenesis.###Define or Characterise: (i) Primary oocyte. (ii) Primary follicle. (iii) Secondary follicle. (iv) Tertiary follicle. (v) Antrum. (vi) Secondary oocyte. (vii) Graafian follicle.

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:
A group of teenagers was involved in drug abuse. 'They used syringes and needles to inject drugs. 'They indulged in this habit when they became adults. Administration of drug through needles became a piece of cake for them. Raj was the most active drug abuser amongst them and used to take drugs in high profile parties. In a span of time he started losing weight and suffered persistent diarrhoea. He developed constant low grade fever and used to catch opportunistic infection. When he consulted a doctor, he got himself tested for HIV in his blood and finally diagnosed with AIDS.
Based on the above information, answer the following questions.

1. Select the incorrect statement.

1. AIDS is a disorder of cell mediated immune system of the body.
2. AIDS is caused by Human Immunodeficiency virus.
3. AIDS infections were detected in India for the first time in prostitutes of Chennai, Tamil Nadu in 1986.
4. December 10 is recalled as World AIDS Day.

2. How do you think Raj got AIDS infection?

1. Through transfusion of HIV infected blood
2. Sexual intercourse with an infected partner
3. Sharing towel with infected friend
4. Use of contaminated needles and syringes to inject drugs

3. How AIDS can be diagnosed?

1. ELISA test
2. Ames test
3. Pap's test
4. Wida! test

4. How can AIDS be prevented?

1. Blood tests of blood donor before transfusion to check for the presence of AIDS virus.
2. Use of disposable needles and syringes for injecting medicines and vaccination
3. Having protected sex by use of condoms
4. All of these

5. Select the correct statement for AIDS virus.

1. It is rhomboid in shape with a diameter of 10-15 cm.
2. Its genome consists of ds DNA.
3. It consists of reverse transcriptase enzyme.
4. Its envelope consists of lipid bilayer and three protein coats.

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

Non-native or alien species are often introduced in advertently for their economic and other uses. They often become invasive and drive away the local species. Exotic species have proved harmful to both aquatic and terrestrial ecosystems. For example, water hyacinth (Eichhornia crassipes) was introduced in Indian waters to reduce pollution. It was clogged water bodies including wetlands at many places resulting in death of several aquatic plants and animals.

1. Island water ecosystem are the most vulnerable due to:

1. Small size.
2. Small number of species.
3. Increases reproductive capacity.
4. Both (a) and (b).

2. Which of the following is not an alien species?

1. Lantana camara.
2. Periplaneta americana.
3. Nile Perch.
4. Yucca moth.

3. Second major cause of species extinction is:

1. Habitat loss and fragmentation.
2. Over exploitation.
3. Alien species invasion.
4. Co-extinction.

4. Assertion: Eichhomia crassipes drains off oxygen from water and can be seen growing in standing water.

Reason: Eichhornia crassipes is an indigenous species of India.

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.

5. The population of species Pin a certain conununity was constant until a population species Q from a distant land was subsequently introduced into that community. The interaction between the two populations is reflected in the graph below.

What could be the possible reason for the decrease in the population of species P over a number of days?

1. Species Q is a predator of species P.
2. Species Q is a prey species which wiped out the population of species P.
3. Species P and Q compete for space but feeds on different food.
4. None of these.