Reproduction in Lower and Higher Animals — BIOLOGY STD 12 Science — Question

Distinguish between : Cranial nerves and Spinal nerves

Distinguish between : Ascariasis and Filariasis.

Distinguish between : FSH and LH

Read the following and answer any four questions from (i) to (v) given below:
Regular change in temperature that occurs at specific intervals of time is called thennoperiodicity. It is of two types-diurnal and seasonal thermoperiodicity. Diumal periodicity refers to temperatures of day and night. It determines periods ofannual activity. In season periodicity different temperature prevails in different seasons of the year. 'Tiley favour different aspects of plant and animal life termed as phenology. For example in wheat, leaf growth requires a temperature of 10º-25ºC. Apple requires temperature below 7ºC for a period of 800 hrs before flowering and fruiting can occur. Low temperature is required for germination of some seeds as well as flowering in some plants. It also determines growth, reproduction, colour and morphology of animals. Both low and high temperature cause stress in organisms which is overcome by particular adaptations.

1. Some plants require low temperature treatment for flowering. This phenomenon is known as:

1. Photoperiodism.
2. Vemalisation.
3. Thermoperiodism.
4. None of these.

2. Animals found in arctic zones are called.

1. microtherms
2. Megatherms
3. Mesotherms
4. Hekistotherms

3. Which of the following parts of wheat plant grows maximum in temperature around 10º-25ºC?

1. Root
2. Seeds
3. Leaf
4. Stem

4. "Different temperatures prevail in different seasons of the year." It represents:

1. Diurnal thermoperiodicity.
2. Seasonal periodicity.
3. Homeostasis.
4. Thermoregulation.

5. Assertion: Low and high temperature causes stress in organisms.

Reasons: Organisms show specific adaptations to overcome stressful condition.

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:
Study the two cases carefully regarding the pattern of inheritance of disease.

Case	Mother	Father	Children
Case I	With disease	Normal	Sons always with diseases
Case II	With disease	Normal	Sons and daughters could show disease

1. Which of the following diseases is not an example of case I?

1. Haemophilia.
2. Colour blindness.
3. Aa, AA, Aa, Aa, aa
4. Night blindness.

2. Which of the following is impossible for a case I?

1. Carrier mother to pass the gene to her son.
2. Diseased father to pass the gene to his daughter.
3. Diseased father to pass the gene to his son.
4. Carrier mother to pass the gene to her daughter.

3. If inheritance pattern of disease is as case II and both parents are carrier of disease what are the chances of pregnancy resulting in an affected child?

1. 25%
2. 100%
3. 0%
4. 50%

4. Disease that follows inheritance pattern as case I is linked with?

1. Autosomes.
2. X chromosome.
3. Y chromosome
4. Chromosome 21.

5. Study the given pedigree chart showing the inheritance pattern as case II.

Study the given pedigree chart showing the inheritance pattern as case II.

1. Aa, aa, aa, AA, aa
2. Aa, aa, Aa, AA, Aa
3. Aa, Aa, aa, AA, AA
4. Aa, AA, Aa, Aa, aa

Read the following and answer any four questions from (i) to (v) given below:
Enzymes are best known for their ability to catalise biochemical reactions without undergoing any change. A large number of enzymes are being used in biotechnological industry. Most of them are obtained from microbes. Proteases degrade proteins and polypeptides. Most of the commercially applicable proteases are alkaline and are biosynthesised mainly by bacteria such as Pseudomonas, Bacillus and some fungi like, Aspergillus. These enzymes are used in clearing beer, softening of bread and meat, degumming of silk, etc. Alkaline serine proteases have the largest applications in bio-industry. Alkaline proteases have shown their capability to work under high pH, temperature and in presence of inhibitory compounds. Another important group of enzymes is amylases. Amylolytic enzymes act on starch. These are obtained from Aspergillus, Rhizopus and Bacillus sp. These are used in softening and sweetening of bread, production of alcoholic beverages from starchy materials, clearing of turbidity in juices caused by starch, etc.

1. Polypeptides are degraded by:

1. Amylases.
2. Proteases.
3. Pectinases.
4. Lipases.

2. Amylolytic enzymes are not obtained from:

1. Aspergillus.
2. Aspergillus.
3. Mucor.
4. Bacillus.

3. Clearing of turbidity in juices caused by starch is achieved by:

1. Amylases.
2. Proteases.
3. Rennet.
4. Both (a) and (b).

4. Select the incorrect option from the following.

1. Enzymes are proteinaceous substances.
2. Enzymes are substrate specific.
3. Enzymes are large sized molecules.
4. Microbial enzymes can work only in normal temperature and pH.

5. A farmer harvests corns and prepares corn starch. He wants to prepare some corn syrup from this. for the conversion he needs to use enzyme ______.

1. Amylase.
2. Glucoamylases.
3. Glucoisomerases.
4. All of these.