Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

Read the following and answer any four questions from (i) to (v) given below:
In today's world, more than 25% of human population is suffering from hunger and malnutrition. Scientists have developed techniques where microbes are grown on industrial scale as a source of good protein which can be grown from waste water, animal manure and even sewage. Single cell proteins are such products. TI1e biomass or protein is extracted from pure or mixed cultures of algae, yeasts, fungi or bacteria. These are a very good source of food for human consumption.

1. Why the name single cell protein is applied?

1. It contains only one type of protein.
2. It is obtained from unicellular edible microbes.
3. It contains only one type of microorganism.
4. All of these.

2. Which of the following is considered under single cell protein?

1. Algae.
2. Fungi.
3. Cyanobacteria.
4. All of these.

3. Microorganisms can be a useful food resource for increasing human population because:

1. These are easy to harvest.
2. These can grow in water system.
3. They have a high rate of multiplication thus producing huge biomass.
4. They have high level of nucleic acid.

4. Single cell protein can be grown from:

1. Waste water.
2. Animal manure.
3. Sewage.
4. All of these.

5. Assertion: Production of single cell protein reduces pollution.

Reason: Single cell protein can be grown from waste water and even sewage.

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.

Distinguish between : Ascariasis and Filariasis.

Distinguish between : Carbon cycle and phosphorus cycle.

Outcrossing and Crossbreeding.

Read the following and answer any four questions from (i) to (v) given below:
A technique known as amniocentesis is used to determine fetal abnormalities. This test chromosomal pattern in amniotic fluid. However, this technique is legally banned now.

1. Identify X and Y in the above given figure.

S. No	X	Y
(a)	Amnion	Chorion
(b)	Uterine wall	Placenta
(c)	Placenta	Uterine wall
(d)	Uterine wall	Amnion

2. What is the function of Z?

1. Z is an amniotic fluid which prevents dessication of an embryo.
2. Z is yolk sac which functions as site of early blood cell formation.
3. Z is amnion, which takes part in placenta formation.
4. None of these

3. Which of the following diseases can not be diagnosed by amniocentesis?

1. Down's syndrome.
2. Sickle cell disease.
3. Jaundice.
4. Cystic fibrosis.

4. Assertion: Amniocentesis is legally banned for sex determination.

Reason: Amniocentesis was being misused for aborting normal female fetus.

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. Which of these is a non-invasive technique of detecting fetal disorder?

1. Fetoscopy.
2. Chorionic villi sampling.
3. Amniocentesis.
4. Ultrasound imaging.

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).