Biodiversity and Conservation — BIOLOGY STD 12 Science — Question

Explain- Restriction enzymes.

Explain: Acquired Immunity.

Early diagnosis is not possible by traditional methods for diagnosis and treatment- discuss in detail.

Explain with diagram - Hershey and Chase experiment.###On the basis of experimental proof explain the diagram that DNA is genetic material.###How did Hershey and Chase differentiate between DNA and protein in their experiment while proving that DNA is the genetic material?

Given below is the pattern of temperature in a person suffering from a non-viral disease transmitted by mosquitoes. Study the graph and answer the questions that follow:

A. Explain the factor(s) responsible for this pattern of temperature.
B. How does this pathogen multiply in the human body?
C. How is this infection transmitted to humans?
OR
D. Which stages of the life cycle of this pathogen are completed in the mosquito's gut?

Read the following and answer any four questions from (i) to (v) given below:
X and Y are communicable diseases, whereas Wand Z are non-communicable diseases.X is transmitted through vectors whereas Y is transmitted through droplet infection. Wis caused due to a hormone deficiency, whereas Z is a degenerative disease. Based on the above information, answer the following questions.

1. Identify W, X, Y and Z.

	W	X	Y	Z
(a)	Coronary artery disease	Cholera	Chikungunya	Chikungunya
(b)	Diabetes	Malaria	Rhinitis	Alzheimer's disease
(c)	Alzheimer's disease	AIDS	Shigella	Plague
(d)	Gonorrhea	Diphtheria	Pertussis	Anthrax

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.

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.

Read the following and answer any four questions from (i) to (v) given below:
DNA fingerprinting is a technique of determining nucleotide sequences of certain areas of DNA which are unique to each individual. Each person has a unique DNA fingerprint. Each fingerprint is the same for every cell, tissue and organ of a person. DNA fingerprinting is the basis of paternity testing in case of disputes.

1. The technique developed to identify a person with the help of DNA restriction analysis is known as.

1. DNA profiting
2. DNA fingerprinting
3. RFLP
4. Both (a) and (b).

2. For DNA fingerprinting, DNA is obtained from.

1. Blood
2. Hair root cells
3. Semen
4. All of these

3. During DNA fingerprinting, the radioactive probes.

1. Hybridise with DNA sample to form double stranded structure
2. Egrade the DNA
3. Create positive charge on DNA
4. Cut the DNA sample at various sites.

4. In India, DNA fingerprinting technique was developed by?

1. Dr. Lalji Singh
2. Alec Jeffreys
3. Dr. Khorana
4. None of these.

5. Which of the following is true about DNA fingerprinting?

1. VNTR is used as probe.
2. DNA samples are loaded on agarose gel electrophoresis.
3. It is based on identification of nucleotide sequence present on the DNA molecule.
4. All of these