Explore topic-wise InterviewSolutions in Current Affairs.

Correct answer is (a) sp² 

(a) Statement-I and II are correct and statement-II is correct explanation of statement-I.

O-nitrophenol is steam volatile due to intramolecular hydrogen bonding and hence can be separated by steam distillation from pnitrophenol which is not steam volatile because of inter-molecular hydrogen bonding. 

This is due to intermolecular hydrogen bonding in carboxylic acids.

The molecular masses of all these compounds are comparable : 

CH₃CHO (44), CH₃CH₂OH (46), CH₃COCH₃ (46), CH₃CH₂CH₃ (44). 

CH₃CH₂OH exists as associated molecule due to extensive intermolecular hydrogen bonding and hence its boiling point is the highest (351 K). Since dipoledipole interaction are stronger in CH₃CHO than in CH₃OCH₃, hence boiling point of CH₃CHO (293 K) is much higher than that of CH₃OCH₃ (249 K). Further, molecules of CH₃CH₂CH₃ have only weak Vander Waals forces while the molecules of CH₃OCH₃ have little stronger dipole-dipole interactions and hence the boiling point of CH₃OCH₃ is higher (249 K) than that of CH₃CH₂CH₃ (231 K). 

Thus the overall increasing order of boiling points is : 

CH₃CH₂CH₃ < CH₃OCH₃ < CH₃CHO < CH₃CH₂O 

The b. pt. of butanol is higher than that of butanal because butanol has strong intermolecular H-bonding while butanal has weak dipole-dipole interaction. However both of them form H-bonds with water and hence are soluble 

(i), (ii)

(i) Benzoyl chloride + Benzene + AlCl₃

(ii) Benzoyl chloride + Diphenyl cadmium

Because of increase in alkyl chain length which is hydrophobic in nature. Hence solubility decreases. 

The compound should have CH₃ CO-group to show the iodoform test. Acetophenone (C₆H₅ COCH₃) contains the group CH₃ CO attached to carbon and hence given iodoform test while benzophenone does not contain this group and hence does not give iodoform test.

C₆H₅ COCH₃ (Acetophenone) + 3I₂ + 4 NaOH → CHI₃ + C₆ H₅ COONa (Iodoform) + 3 NaI + 3 H₂O 

C₆ H₅ COC₆H₅ + I₂ + NaOH → No reaction

The nutrient required in trace amounts to accomplish various body functions is Vitamin.

The sprouting of onion and potatoes can be delayed by the process of Irradiation.

1. False.

Correct Statement: Iodine is required for the proper functioning of thyroid gland.

2. False.

Correct Statement: Vitamins are required in small quantities for normal functioning of the body.

3. True

5. False.

Correct Statement: AGMARK is mandatory to certify Agricultural products.

The physician who discovered that Scurvy can be cured by ingestion of citrus fruit is James Lind.

• Name of the product – Thenkuzhal.
• Manufacturer’s details – Sri Krishna Sweets. Handmade to provide authentic taste.
• Ingredients – Rice flour, Refined vegetable oil, Urud dhal, Butter, Iodized salt, Cumin, Asafoetida.
• Net weight – 500 gms.
• Maximum Retail Prize – (MRP) ? 100.
• Date of Manufacture – 09.04.2018.
• Date of Expiry – Best before 30 days from the date of manufacture.

• Increases the impurity in the food items 
• Lack of Nutritional value 
• Leads to various diseases

1. Name of the product 

2. Manufacturer’s details, Contents/Ingredients 

3. Net Weight 4. Maximum Retail Price (MRP) 

5. Date of Manufacture 

6. Date of Expiry 

7. Date of best before us

Iron deficiency is the most common nutrient deficiency in adolescent girls. Insufficient iron can lead to anaemia. Leafy vegetables and dates are rich in iron and other minerals. So the doctor advises to include more of these in the diet.

Vitamins boost the immune system, support normal growth and development.

The binding force between antigen and antibody is due to three factors. They are closeness between antigen and antibody, noncovalent bonds or intermolecular forces and affinity of antibody.

(c) Antigen binding site on variable regions

Paratope is antigen binding site that is present on the antibodies.

1. Epitope: Epitope is an antigenic determinant and is ‘ the active part of an antigen. 

2. Paratope: A paratope is the antigen – binding site and is a part of an antibody which recognizes and binds to an antigen.

Interferons are antiviral proteins 

They are the included in chemical mediators of innate immunity

Role : They act against invading viral particles

Normal Cells: 

1. Small uniformly shaped nuclei Relatively large cytoplasmic volume 

2. Conformity in cell size and shape Cells arranged into discrete tissue 

3. May possess differentiated cell structures Normal presentation of cell surface markers

4. Lower levels of dividing cells Cell tissues clearly demarcated

Cancer Cells:

1. Large, variable shaped nuclei Relatively small cytoplasmic volume 

2. Variation in cell size and shape Disorganised arrangement of cells 

3. Loss of normal specialised features Elevated expression of certain cell markers 

4. Large number of dividing cells Poorly defined tumor boundaries

(d) All the above

c) Antigen binding site on variable regions

Dendritic cells are called so because its covered with long, thin membrane extensions that resemble dendrites of nerve cells. These cells present the antigen to T-helper cells.

Correct answer is (c) Paul Ehrlich

Correct answer is (a) Streptococcus sps

I. Diagnosis and Treatment : 

For the patient, diethyl-carbamazine citrate is the drug used for twice a day for three weeks. Thereafter for five days every six months the same treatment is repeated. This becomes effective against filarial worms.

II. Prevention and Control:

1. Mosquito eradication should be done for controlling filariasis. 

2. In the areas with mosquitoes, avoid mosquito bite by using mosquito nets and insect repellents.

Autoimmunity is due to an abnormal immune response in which the immune system fails to properly distinguish between self and non-self and attacks its own body.

(c) Poliomyelitis

Correct answer is (b) Typhoid

1. Lymphocyte 

2. Monocytes

Due to the establishment of immunological memory of the first encounter, the secondary immune response highly intense and effective.

Lymphocytes: About 20-30% of the white blood cells are lymphocytes. They have a large nucleus filling most of the cell, surrounded by a little cytoplasm. The two main types of lymphocytes are B and T lymphocytes. Both these are produced in the bone marrow. B lymphocytes (B cells) stay in the bone marrow until they are mature. Then they circulate around the body. Some remain in the blood, while others accumulate in the lymph nodes and spleen. T lymphocytes leave the bone marrow and mature in the thymus gland. Once mature, T cells also accumulate in the same areas of the body as B cells. Lymphocytes have receptor proteins on their surface. When receptors on a B cell bind with an antigen, the B cell becomes activated and divides rapidly to produce plasma cells. The plasma cells produce antibodies. Some B cells do not produce antibodies but become memory cells.

These cells are responsible for secondary immune response. T lymphocytes do not produce antibodies. They recognize antigenpresenting cells and destroy them. The two important types of T cells are Helper T cells and Killer T cells. Helper T cells release a chemical called cytokine which activates B cells. Killer cells more around the body and destroy cells which are damaged or infected. Apart from these cells neutrophils and monocytes destroy foreign cells by phagocytosis. Monocytes when they mature into large cells, they are called macrophages which performs phagocytosis on any foreign organism.

Dendritic cells are called so because its covered with long, thin membrane extensions that resemble dendrites of nerve cells. These cells present the antigen to T-helper cells. Four types of dendritic cells are known. They are langerhans, interstitial cells, myeloid and lymphoid cells.

Appearance of merozoites in a patients blood may be an indication of malarial parasite – plasmodium.

There are four stages of clinical manifestations or symptoms of AIDS.

1. Stage I : This is initial infection with the virus and formation of antibodies, usually 2-8 weeks after initial infection. 

2. Stage II : In this stage the person is asymptomatic carrier. Incubation takes place with a period ranging for 6 months to 10 years.

3. Stage III : This is called AIDS related complex (ARC). In this stage, one or more of the following clinical signs are seen. 

E.g. Recurrent fever for longer than one month, fatigue, unexplained diarrhoea, night sweats, shortness of breath, loss of more than 10 per cent body weight, etc. 

4. Stage IV : This is the end stage in which patient shows full blown AIDS. Thus it is called the end stage of HIV infection. Life threatening opportunistic infections (like pneumonia, tuberculosis, Kaposi sarcoma, etc.) are easily caught during this period.

(a) saliva of infected female Anopheles mosquito.

(a) Western blot

(b) reverse transcriptase

Autoimmune diseases : Autoimmunity is due to an abnormal immune response in which the immune system fails to properly distinguish between self and non-self and attacks its own body. Our body produces antibodies (auto antibodies) and cytotoxic T cells that destroy our own tissues. If a disease-state results, it is referred to as auto-immune disease. Thus, autoimmunity is a misdirected immune response.

I. Laboratory diagnosis :

1. There are two tests for diagnosis of AIDS. 

2. First test is ELISA (Enzyme-Linked Immunosorbent Assay) which is used to detect the HIV antibodies.

3. The second confirmatory test is Western Blot, which is used to weed out any false positive results. It is a highly specific test. 

4. It is based on detecting specific antibody to viral core protein and envelope glycoprotein.

II. Treatment of AIDS:

1. AIDS cannot be cured. 

2. Antiretroviral drugs are used to reduce the viral load and prolong the life of HIV patient. E.g. Antiretroviral therapy (ART) uses drugs such as TDF (tenofovir), EFV (Efavirenz), Lamivudine (3TC), etc.

(d) (A) is false (R) is true

Typhoid is caused due to Salmonella typhi which isa Gram-negative bacterium, transmitted from a patient or carrier to another healthy person through contaminated food or water. Flying insects, mostly houseflies transmit the bacteria from faeces to the food. Poor hygienic habits and improper public sanitation system spreads typhoid. Therefore, it is said to be food and water-borne disease

Correct answer is (a) (A), (C), (F), (G)

(1) Stage II is completed in human.

(2) Humans are infected at step 1 when mosquito bites human and larvae enter blood stream. In step 2 adult Wuchereria worms are formed in lymphatics.

(3) Mosquito carries the blood as it bites the human in step 4 and ingests microfilariae in human blood. Later the microfilariae start growing in the midgut of mosquito.

(4) Stage I is completed in mosquito.

The transmission of HIV occurs through following routes:

1. Sexual relations, mainly unsafe sexual contact including oral, vaginal and anal sex. 

2. Through blood and blood products either by blood transfusions or sharing needles and syringes. 

3. Transplacental From pregnant mother to her foetus through placenta. Nursing mother can also transmit HIV to her baby through lactation. 

4. Spreading the virus is very rare in case of accidental needle injury, artificial insemination with infected donated semen and transplantation with infected organs.

5. HIV is seen in urine, tears, saliva, breast milk and vaginal secretions but unless these body fluids enter the injuries and wounds, transmission is not easy.