BT102 Final Term Current Solved Questions by Arif Khan

Bt102 Current final term Questions solved by

M Arif khan. (2021)

Q1. What is reverse transcription? 2marks

Answer: A process in which reverse transcriptase enzyme is used to generate complementary DNA from an RNA template is called Reverse transcription.

Q2. What is epidemiology? Write the study method of epidemiology. 3-marks

Answer: The study of the distribution and determinants of health-related states and events in specified populations is called epidemiology. The study of this application is to the control of health problems

Following are the broad categories of epidemiological studies;

• Cross-sectional studies.
• Case-control studies.
• Cohort studies.
• Intervention studies

Q3. Explain the following types of algae. ( 5-marks)

Phaeophyta (Kelp):

• Commonly known as brown algae. Brownish in color and contains cellulose aliginic acid cell walls.
• These are multi-cellular and contain chlorophyll a and c, xanthophylls. These store carbohydrates and used for algin.

Rhodophyta.

• Red-dish in color and Contains Cellulose cell walls.
• Most are Multi-cellular and Contains Chlorophyll a and d.
• Store glucose polymer.

Chlorophyta.

• These are green algae and contains Cellulose cell walls
• These are Unicellular or multi-cellular and Contains Chlorophyll a and b
• Store glucose polymer
• Rise to terrestrial plants

Bacillariophyta.

• These are Brownish in color and Contains cell wall which is composed of Pectin and silica.
• These are Unicellular and Contains Chlorophyll a and c, carotene, xanthophylls.
• Store oil and fossilized diatoms formed oil.

Dinoflagellata.

• These are Brownish in color. Contains Cellulose in plasma membrane.
• These are Unicellular. Contains Chlorophyll a and c, carotene.
• Store starch.

Q4. Explain Natural immunity, Aquired active and passive immunity. 3mrks

Natural immunity: Immunity that naturally existing is called natural immunity. Natural immunity does not require prior sensitization to an antigen

Aquired Active Immunity: Acquired active immunity occurs when the individual is introduced to a live microorganism develops the disease and gets safe due to the fundamental safe response. Passive Immunity: Passive immunity is the protection from a disease provided by antibodies created outside of the body. Passive immunity can occur naturally, when maternal antibodies are transferred to the fetus through the placenta.

Q5. What is Plaque? 2marks

Answer: A plaque is an area where the virus infection has lysed the cells. e.g: Dental plaque is an example of bio-film.

Q6. What is hypersensitivity? Explain its four types? 5-marks

Answer: Answer: Hypersensitivity means the undesirable reactions produced by the normal immune system including allergies and auto-immunity.

Types: Following are the four types of hypersensitivity;

Type-I hypersensitivity: Type-1 hypersensitivity reaction is an allergic reaction provoked by showing to a specific type of antigen referred to as an allergen. The reaction may be either local or systemic. Its examples are Asthma and dermatitis.

Type-II hypersensitivity: Type-II hypersensitivity reaction is an antibody-mediated immune reaction in which antibodies are directed against cellular or extracellular matrix antigens. That results cellular destruction, functional loss, or damage to tissues.

Type-III hypersensitivity: Type-III hypersensitivity occurs when there is an excess of antigen leading to small immune complexes being formed. That fixed complement and are not cleared from the circulation. It involves soluble antigens that are not bound to cell surfaces

Type-IV hypersensitivity: Type-IV hypersensitivity also called delayed-type hypersensitivity which involves T-cell antigen interactions that cause activation and cytokine secretion. This type of hypersensitivity requires sensitized lymphocytes that respond 24–48 h after showing to soluble antigens.

Q7. Name the drugs which resist cell wall? 2marks

Answer: Penicillin and cephalosporin are the major drugs (antibiotics) that inhibit bacterial cell wall synthesis. They are called beta-lactams.

Q8. Explain Primary and secondary immune response. 5marks

Primary immune Response: The primary immune response occurs when an antigen comes in contact to the immune system for the first time. During this time the immune system has to learn to recognize antigen and how to make antibody against it and at last produce memory lymphocytes.

Secondary immune Response: The secondary immune response occurs when the second time the person is exposed to the same antigen. At this point immunological memory has been established and the immune system can start making antibodies immediately.

During the secondary immune response, memory T-cells rapidly generate into active helper Tcells specific to that antigen, while memory B-cells rapidly produce antibodies to neutralize the pathogen.