Applications of given components are as follows
(i) Passive immunisation provides a faster immune response.
(ii) Antihistamine is used to reduce the symptoms of allergy such as sneezing, watery eyes, rashes, running nose, etc.
(iii) Colostrum consists of antibodies (e.g. IgA) that provide immunity to an infant against infections.
(iv) Cytokinin barrier produces interferons and protects non-infected cells from further viral infection.

(i) A doctor would recommend preformed antibodies in an injured person in an accident on snake bites and tetanus.  The type of immunization is passive immunization.
Its advantages are:
(a) Provides immediate relief.
(b) Used either prophylactically or therapeutically.
(ii) Passive immunity

A state of complete physical, mental & social well - being. A healthy person is more efficient at work. Increases productivity & brings economic prosperity.

(i) (vi);
(ii) (v);
(iii) (iv);
(iv) (iii);
(v) (ii);
(vi) (i);
(vii) (viii);
(viii) (vii)

(i) Diagram illustrates the structure of an antibody molecule.
(ii) 'a' - antigen binding site; 'b' - Variable region of the heavy peptide chain.
(ii) B-lymphocytes and T - lymphocytes.

(a)Antibodies.Refer to terms to memorize.
(b)Helper T-cells,These cells stimulate the B-cells to produce antibodies.They also stimulate the killer T-cells to destroy the non-self cells.
(c) HLA proteins.(Human Leucocyte antigen protein).Chromosome 6 of mouse contains a cluster of genes known as major histocompatibility complex.In human, it is called human leucocyte antigen (HLA complex).The alleles of HLA genes are codominant.
The product of theses genes determine histocompatibility.
(d)B-cells.B-cells are produced in bone marrow.The b-cells direct the antibody mediated immunity.
(e)Complement proteins.These proteins participate in both innate and acquired immunities.They are about 30 proteins that act in various ways to protect the individuals in different ways.They form transmembrane pores which lead to lysis.

(a)Gametocytes.
(b)Release of haemozoin in blood.

(a) AIDS
(b)  HIV
(c)  Helper \({ T }_{ 4 }\) lymphocytes and macrophages.

(i) The mucus coating of the gut epithelium is a barrier that traps microbes.
(ii) The hydrochloric acid secreted by gastric glands retards the growth of microbes.
This type of immunity is called innate immunity, which occurs right from birth.

Carcinogens induce transformation of normal cells into neoplastic cells.

Carcinogenic ionising radiation;e.g. X-rays and carcinogenic non-ionising radiation ,e.g. UV-rays,cause damage to DNA that leads to transformation of these normal cells into neoplastic cells.

An autoimmune disease is produced when the immune system goes off the track and starts attacking the 'self' calls,due to genetic or other unknown reasons,e.g. Rheumatoid arthritis. 

After entering the macrophage,the RNA of the virus produces DNA catalysed by the enzyme reverse transcriptase.

This viral DNA gets incorporated into the DNA of the host cell or macrophage and directs the host cell to produce virus particles.

The macrophage continues to produce new viruses and thus,acts as a HIV factory.

Smack is obtained from Papaver somniferum. It affects the Central Nervous System (CNS) and gastrointestinal system. It slows down the body functions. It acts as a depressant.

Two special types of lymphocytes in humans are B-lymphocytes and T-lymphocytes. B-lymphocytes execute antibody-mediated response while T-lymphocytes show cell-mediated response.

B-lymphocytes and T-lymphocytes

Both these types of cella multiply and produce a clone of cells.

B-lymphocytes produce an array of proteins,called antibodies.

The T-lymphocytes stimulate the B-cells to produce antibodies.

Memory B-cells and T-cells remain inthe body,for secondary immune response,in case of subsequent encounter by the pathogen.

Amoebiasis  

Large intestine

Houseflies.

Entamoeba histolytica

Typhoid

Salmonella typi

Widal test

Transmission is by contaminated food and water.

1. Tetanus antitoxin,i.e. preformed antibodies for tetanus are injected,as the child infected with deadly microbe (tetanus bacteria) to which quick immunisation response is required.
2. If tetanus vaccine is injected,it will take some time for the body to develop antibodies and this can lead to a fatal end.

Tetanus antitoxin,i.e. preformed antibodies for tetanus are injected,as the child infected with deadly microbe (tetanus bacteria) to which quick immunisation response is required.

If tetanus vaccine is injected,it will take some time for the body to develop antibodies and this can lead to a fatal end.

Active immunity is produced by injecting the microbes deliberately during immunisation.

Antibodies are produced by the B-cells of our body in response to the antigens;they neutralise the pathogenic agents during actual infection.

The vaccines also generate memory B-cells and T-cells,which recognise the same pathogen on subsequent exposure and destroy them by a massive production of antibodies.

1. Active immunity is produced by injecting the microbes deliberately during immunisation.
2. Antibodies are produced by the B-cells of our body in response to the antigens;they neutralise the pathogenic agents during actual infection.
3. The vaccines also generate memory B-cells and T-cells,which recognise the same pathogen on subsequent exposure and destroy them by a massive production of antibodies.

Active immunity is produced by injecting the microbes deliberately during immunisation.

Antibodies are produced by the B-cells of our body in response to the antigens;they neutralise the pathogenic agents during actual infection.

The vaccines also generate memory B-cells and T-cells,which recognise the same pathogen on subsequent exposure and destroy them by a massive production of antibodies.

Active immunity is produced by injecting the microbes deliberately during immunisation.

Antibodies are produced by the B-cells of our body in response to the antigens;they neutralise the pathogenic agents during actual infection.

The vaccines also generate memory B-cells and T-cells,which recognise the same pathogen on subsequent exposure and destroy them by a massive production of antibodies.

It is called allergy.

It is due to the release of histamine and serotonin by mast cells.

(i) MALT - Mucosal Associated Lymphoid Tissue
(ii) CMI - Cell-Mediated Immunity
(iii) AIDS - Acquired Immuno Deficiency Syndrome
(iv) NACO - National AIDS Control Organisation
(v) HIV - Human Immunodeficiency Virus

Viral diseases:
1.polio caused by Entiro virus and polio virus 
2.Rabies caused by Rabies virus.
(ii)AIDS is a dread viral diseases.Measures to avoid AIDS.
1.Avoid sexual contact with infected person or multiple partner.
2.Use condom during sexual act.
3.Avoid use of infected syringes.

(i) Histamines cause reactions of the immune system against allergens.
(ii) Interferons protect the non-infected cells of our body from viral infections.
(iii) B-cells produce antibodies against antigens/pathogens.

(a) Amoebiasis is caused by Entamoeba histolytica.
(b) Symptoms:
(i) Constipation 
(ii) Abdominal cramps and pain.
(iii) Stool with excess mucus and blood clots.
Transmission 
Drinking water and food contaminated with the faeces of infected persons.
Houseflies act as mechanical carriers and transmit the parasite from faeces to food and water.