Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

Explain innate immunity in detail

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.

Differentiate between Monohybrid & Dihybrid Cross.

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

Ananya is a biologist, her research guide assigned project, i.e., to determine the effect ofin tra-specific competition on the growth of sapling of Eucalyptus. For this, she designed an experiment in which two sets of pots were used. ln the first set (set A) only I sapling was planted per pot and in the other set (set B) 16 saplings were planted per pot. To check for the effect of intra-specific competition on allocation of resources, a decreasing amount of water was added to each set. The results have been graphically indicated. Which of the following conclusions can indicated as follows:

1. Which of the following statements can be concluded from the given study?

1. More resources are allocated to the root during low water conditions.
2. Competition for water among individuals of a population causes more root growth as compared to individuals who are growing alone.
3. Lesser leaves are formed under low water conditions.
4. Root growth is higher in individual grown singly as compared to individuals in populations.

2. Which of the following associations is an example of competitions?

1. Cuscuta and hedge plant.
2. Balanus and Cathamalus.
3. Cactus and moth.
4. Orchid and mango.

3. If '+' sign is assigned to beneficial interaction, '-' sign to detrimental and O sign to neutral interaction, then the population interaction of competition refers to:

1. +, +
2. -, -
3. +, -
4. +, 0

4. lntraspecific competition is more severe due to:

1. similar needs.
2. similar adaptations.
3. common resources.
4. all of these.

5. Assertion: Two members of a competing species may co-exist.

Reason: Different individuals of a species have different resource requirements.

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 a study to test a new vaccine against a viral disease, mouse model testing is done. In this process, mice are vaccinated and their blood samples were tested. Mice developed mild disease symptom. After few days those mice were again infected with the virus. This time they do not show any disease symptoms. Their blood samples were tested. Two graphs show antibody concentration for the first and second infection in mice blood.

Based on the above information, answer the following questions.

1. P and Qin the given graphs indicate.

1. IgM and IgG respectively.
2. IgG and IgM respectively
3. IgG and IgM respectively
4. IgM and IgA respectively.

2. Which form of pathogen is used in vaccination?

1. Activated and strong pathogenic antigen.
2. Inactivated and weakened pathogenic antigen.
3. Hyperactive and strong pathogen.
4. Preformed antibodies.

3. Which of the following is incorrect for P?

1. It is the most abundant class of lg.
2. It is found in blood, lymph, and intestine.
3. It is unable to cross the placental barrier.
4. It is a monomer.

4. How does vaccination work?

1. The immune system produces antibodies which stay in the blood.
2. Memory lymphocytes remain in the body to fight off any future infection with the same pathogen.
3. The dead pathogen stays in the body and constantly stimulates the immune system.
4. All of these.

5. Assertion: Mice do not show any disease symptoms during second exposure to the pathogenic virus.

Reason: The antibody production is accelerated and more intense during secondary immune response.

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 different outbreeding devices in detail.###Describe different devices to discourage self pollination.###Describe different devices to encourage cross pollination.

Explain- Restriction enzymes.

Describe the process of translation during protein synthesis

Assuming that within a population of beetles where Hardy Weinberg conditions are met, the colour black (B) is dominant over the colour red (b). 40% of all beetles are red (bb).
Given this information, answer the questions below:
A. What is the frequency of red beetles?
B. Calculate is the percentage of beetles in the population that are heterozygous.
C. What is the frequency of homozygous dominant individuals?
OR
D. Assuming that Hardy Wienberg conditions are met in the beetle population consisting of 1500 beetles. How many beetles would you expect to be black and red in colour respectively?