CHSE Odisha Class 12 Biology Important Questions Chapter 9 Health and Diseases

Odisha State Board CHSE Odisha Class 12 Biology Important Questions Chapter 9 Health and Diseases Important Questions and Answers.

CHSE Odisha 12th Class Biology Important Questions Chapter 9 Health and Diseases

Health and Diseases Class 12 Important Questions CHSE Odisha

Very Short Answer Type Questions

Choose the correct option

Question 1.
Which of the following diseases are communicable?
(a) Deficiencies
(b) Allergies
(c) Degenerative diseases
(d) Infectious diseases
Answer:
(d) Infectious diseases

Question 2.
The malignant malaria is caused by
(a) Plasmodium vivax
(b) Plasmodium malariae
(c) Plasmodium ovale
(d) Plasmodium falciparum
Answer:
(d) Plasmodium falciparum

Question 3.
Which is the infective stage of Plasmodium falciparum?
(a) Sporozoite
(b) Trophozoite
(c) Cryptozoite
(d) Merozoite
Answer:
(a) Sporozoite

Question 4
………… causes common cold.
(a) Virus
(b) Bacteria
(c) Protozoa
(d) Fungus
Answer:
(a) Virus

Question 5.
The confirmative test for typhoid is ………….. .
(a) Widal
(b) Mantoux
(c) CBC
(d) PCR
Ans.
(a) Widal

Question 6.
Through which vector is Wuchereria bancrofti transmitted?
(a) Anopheles
(b) Aedes
(c) Culex
(d) Tes-tse fly
Answer:
(c) Culex

Question 7.
The disease filariasis is caused by
(a) Treponema pallidum
(b) Neisseria gonorrhoeae
(c) Mycobacterium leprae
(d) Wuchereria bancrofti
Answer:
(d) Wuchereria bancrofti

Question 8.
Which parasitic causes amoebic dysentery?
(a) Escherichia coli
(b) Amoeba proteus
(c) Entamoeba histolytica
(d) Plasmodium vivax
Answer:
(c) Entamoeba histolytica

Question 9.
Which of the following is not a congenital disease?
(a) Haemophilia
(b) Down’s syndrome
(c) Cold
(d) Colour blindness
Answer:
(c) Cold

Question 10.
Common symptoms of typhoid are
(a) high fever and weakness
(b) stomach pain and constipation
(c) headache and loss of appetite
(d) All of the above
Answer:
(d) All of the above

Question 11.
Female Anopheles is a vector of
(a) fllariasis
(b) malaria
(c) typhoid
(d) AIDS
Answer:
(b) malaria

Question 12.
Which of the following is a pair of bacterial diseases?
(a) Typhoid and pneumonia
(b) Malaria and AIDS
(c) Ringworm and AIDS
(d) Cold and malaria
Answer:
(a) Typhoid and pneumonia

Question 13.
During allergic reactions which of the following is secreted?
(a) Allergens
(b) Histamines
(c) Immunoglobulins
(d) Pyrogens
Answer:
(b) Histamines

Question 14.
Cancer is
(a) non-malignant tumour
(b) controlled division of cells
(c) unrestrained division of cells
(d) microbial infection
Answer:
(c) unrestrained division of cells

Question 15.
The spread of cancerous cells to distant sites is termed as
(a) metamorphosis
(b) metagenesis
(c) metastasis
(d) metachrosis
Answer:
(c) metastasis

Question 16.
Blood cancer is called
(a) leukaemia
(b) haemophilia
(c) thrombosis
(d) haemolysis
Answer:
(a) leukaemia

Question 17.
Immunodeficiency syndrome could develop due to
(a) defective thymus
(b) defective liver
(c) weak immune system
(d) AIDS virus
Answer
(d) AIDS virus

Question 18.
Cirrhosis of liver is caused by the chronic intake of
(a) alcohol
(b) tobacco (chewing)
(c) cocaine
(d) opium
Ans.
(a) alcohol

Question 19.
Caffeine is a stimulant present in
(a) coffee
(b) tea
(c) cold drinks
(d) All of these
Ans.
(d) All of these

Question 20.
Cannabis sativa is the source of
(a) opium
(b) LSD
(c) marijuana
(d) cocaine
Ans.
(c) marijuana

Question 21.
The drug which is used for reducing pain is
(a) opium
(b) hashish
(c) bhang
(d) marijuana
Ans.
(a) opium

Question 22.
A tranquilliser is drug which
(a) relieves pain
(b) gives soothing effect to mind
(c) induces sleep
(d) has stimulating effect
Answer:
(a) relieves pain

Question 23.
The drug changes the person’s thought is
(a) cocaine
(b) barbiturate
(c) hallucinogens
(d) insulin
Answer:
(c) hallucinogens

Question 24.
Which one of the following is not correctly matched?
(a) Glossina palpalis – Sleeping sickness
(b) Culex – Filariasis
(c) Aedes – Yellow fever
(d) Anopheles – Leishmaniasis
Answer:
(d) Anopheles – Leishmaniasis

Question 25.
Stomach cleans pathogen by
(a) HCl
(b) gastric hormones
(c) Both (a) and (b)
(d) None of these
Answer:
(b) gastric hormones

Question 26.
Ability of body to fight against disease is called
(a) susceptibility
(b) immunity
(c) vulnerability
(d) irritability
Answer:
(b) immunity

Question 27.
Antigen binding site is present on antibody between
(a) two heavy chains
(b) two light chains
(c) one heavy and one light chain
(d) normal chains
Answer:
(b) two light chains

Question 28.
Which of the following is an opiate narcotic?
(a) Morphine
(b) LSD
(c) Amphetamines
(d) Basbiturates
Answer:
(a) Morphine

Question 29.
Which part of the brain is involved in loss of control when a person drinks alcohol?
(a) Cerebrum
(b) Medulla oblongata
(c) Cerebellum
(d) Pons Varolii
Ans.
(c) Cerebellum

Correct the statements, if required, by changing the underlined word(s)

Question 1.
The diseases which occur due to change in chromosomal structure are called degenerative diseases.
Answer:
congenital diseases

Question 2.
Plasmodicum vivax causes cerebral malaria.
Answer:
Plasmodium falciparum

Question 3.
The toxin released due to rupture of RBCs in malaria is haemoglobin.
Answer:
haemozoin

Question 4.
The other name for filariasis is amoebic dysentery.
Answer:
elephantiasis

Question 5.
Ringworm is a viral disease.
Answer:
fungal disease

Question 6.
Typhoid is diagnosed by Mantoux test.
Answer:
Widal test

Question 7.
Antibody-mediated immunity helps the body to differentiate between self and non-self cells during organ transplantation.
Answer:
Cell-mediated immunity

Question 8.
Cellular changes in body as a result of any wound or injury is called immunisation.
Answer:
inflammation.

Question 9.
Cellular barriers forms first line of defence.
Answer:
Physical barriers.

Question 10.
Viral oncogenes on activation lead to tumour formation.
Answer:
Cellular oncogenes

Question 11.
Which test is conducted to identify HIV ?
Answer:
ELISA

Question 12.
HIV is treated using a combination of madicines called antibacterial therapy.
Answer:
antiretroviral.

Question 13.
The ookinete penetrates through the stomach wall and encysts as an gamete.
Answer:
oocyst

Question 14.
Active immunisation against tetanus and diphtheria is achieved by antibiotics.
Answer:
exotoxins or toxoides

Question 15.
Caffeine is used to make tobacco.
Answer:
Nicotiana tabacum is used to make tobacco.

Question 16.
The mood altering drugs are tranquilisers.
Answer:
The mood altering drugs are psychotropic drugs.

Question 17.
Benzodiazepines is used as a stimulant.
Answer:
Cocaine is used as a stimulant.

Question 18.
Antibody production is assisted by monocytes.
Answer:
B-cells

Question 19.
Cell-mediated immunity is mainly function of paratope.
Answer:
T-cells

Express in one or two word(s)

Question 1.
What is called protein pathogen that does not contain nucleic acid?
Answer:
Prions.

Question 2.
The nature of spread of communicable disease.
Answer:
Epidemiology

Question 3.
Name the test specifically employed to determine the presence of disease causing Salmonella typhi.
Answer:
WIDAL Test

Question 4.
Causative organism of malignant malaria.
Answer:
Plasmodium falciparum

Question 5.
Ringworms belong to the fungal genus.
Answer:
Microsporum

Question 6.
The disease transmitted through contact.
Answer:
Measles

Question 7.
An oral dose of drug given for amoebiasis treatment.
Answer:
Metronidazole

Question 8.
Colostrum is rich in which type of antibody(20l9>
Answer:
IgA

Question 9.
The type of immunisation performed for treating snake bite.
Answer:
Passive immunisation.

Question 10.
The type of immunity responsible for graft rejection.
Answer:
Cell-mediated immunity.

Question 11.
The genetic material of HIV?
(Only DNA, only RNA, Both DNA and RNA, Nucleoproteins)
Answer:
Only single-stranded RNA.

Question 12.
The tissue affected in sarcoma.
Answer:
Bone, muscle and lymphnode

Question 14.
The test conducted to detect HIV infection.
Answer:
ELISA, PCR test

Question 15.
What is the source of LSD?
Answer:
Claviceps purpurea

Question 16.
Give one psychological disorder that occurs due to drug addiction.
Answer:
Epilepsy

Question 17.
Which type of drug is used as tranquliser?
Answer:
Benzodiazepines

Question 18.
Name the drug obtained from coca plant.
Answer:
Cocaine

Fill in the blanks

Question 1.
The asexual cycle of Plasmodium in its primary host …………. .
Answer:
humans

Question 2.
The infective stage of malaria parasite is ………….. .
Answer:
sporozoite

Question 3.
Filariasis is caused by ………… .
Answer:
Wuchereria bancrofii

Question 4.
A parasite …………. causes abdominal pain, constipation, cramps, faeces with excess mucus and blood clots.
Answer:
Entamoeba histolytica

Question 5.
A disease causing agent is called …………. .
Answer:
pathogen

Question 6.
The vaccine used against typhoid fever is …………. .
Answer:
Vi antigen

Question 7.
…………. is acquired through vaccines which generate antibodies when introduced in body.
Answer:
Artificial active immunity

Question 8.
IgE are the antibodies involved in ………….. .
Answer:
allergic reaction

Question 9.
Cancer of muscle is named as …………… .
Answer:
sarcoma

Question 10.
………………. tests are conducted to know number of cell counts during cancer.
Answer:
Blood and bone marrow

Question 11.
HIV virus belongs to a group of …………… .
Answer:
retrovirus

Question 12.
Anti Tetanus Serum (ATS) administration generates ………….. immunity in the body.
Answer:
artificial passive

Question 13.
AIDS virus has ……….. RNA.
Answer:
single-stranded

Question 14.
…………. is the most common skin problem that occur during adolescence.
Answer:
Acne

Question 15.
The strong sense of fear in reference to a particular situation or thing is called …………… .
Answer:
phobia

Question 16.
LSD is a natural drug.
Answer:
psychedlic/hallucinogens

Question 17.
Cocaine is obtained from the plant
Answer:
Erythroxylon coca

Question 18.
…………. are antisleep drugs.
Answer:
Amphetamines

Question 19.
Tobacco is obtained from ……………. .
Answer:
Nicotiana tabacum leaves

Question 20.
Pathogen causing ascariasis is ………….. .
Answer:
Ascaris lumbricoides

Question 21.
Phenomenon of rejection of self cells is called ………….. .
Answer:
Autoimmunity

Short Answer Type Questions

Question 1.
Define health and disease.
Answer:

• Health is defined as a state of complete physical, mental and social well-being.
• Disease is a state when functioning of one or more organs or systems of the body is adversely affected.

Question 3.
What are the two basic groups of diseases? Give one example of each group.
Answer:
Two basic groups of diseases are

• Infectious diseases are those which has the ability of transmitting from one person to another, e.g. AIDS, common cold, etc.
• Non-infectious diseases which does not have the ability of transmitting from one person to another, e.g. cancer, diabetes, etc.

Question 4.
Write a short note on pathogens.
Answer:
Organisms that cause infectious diseases are known as pathogens. These can harm any living individual or organism by living on them or living in them.
These disrupt the normal physiology of organisms either plants or animals and express certain symptoms. These enter in our body through some source like air, water, food, soil, etc.
The major classes of pathogens are viruses, bacteria, fungi, prions and parasitic.

Question 5.
Name two bacterial diseases of human.
Answer:
Two bacterial diseases of human are

• Typhoid It is caused by bacterium (Salmonella typhi) which enters the body through food.
• Pneumonia It is caused by bacterium (Streptococcus pneumoniae) which infect alveoli of the lungs.

Question 6.
State the symptoms of typhoid.
Answer:
The incubation period of parasite is about 1-2 weeks and the duration of illness is about 4-6 weeks. The symptoms of typhoid include fever (39-40°C), lethargy, stomach pain, headache, poor appetite, diarrhoea or constipation and rose spots on abdomen. The intestinal perforation or bleeding may occur in severe cases, which may lead to death. The reccurrence (relapsing) of disease is observed in 10% of patients. Typhoid is diagnosed by WIDAL test.

Question 7.
Answer the following
(i) Name the stage of Plasmodium that gains entry into the human body.
(ii) Explain the cause of periodic recurrence of chill and high fever during malaria attack in human.
Answer:
(i) Sporozoite stage.
(ii) When the Plasmodium enters the RBCs, it causes the rupture of red blood cells. The rupture of RBCs, is associated with the release of chemical haemozoin which causes frequent chills and high fever.

Question 8.
Name the toxin responsible for the appearance of symptoms of malaria in human. Why do these symptoms occur periodically?
Answer:
The toxin responsible for symptoms of malaria is haemozoin. It is released when RBCs get ruptured due to erythrocytic schizogony of Plasmodium that takes place every 48 hours. This is the reason behind periodic occurrence of symptoms.

Question 9.
What is the causative organism of amoebiasis? State the symptoms of the disease.
Answer:

• Amoebiasis is caused by an intestinal endoparasite, Entamoeba histolytica.
• Symptoms of amoebiasis are abdominal pain constipation, cramps, faeces with excess mucous and blood clots.

Question 10.
List the symptoms of ascariasis. How does a healthy person acquire this infection?
Answer:
Symptoms
Most of the patients during light infection do not show any symptoms of Ascaris. However, patients with moderate to heavy infections show some symptoms depending upon the infected organ

1. If intestine is infected Ascaris eggs reach to small intestine through contaminated food or water. They hatch and develop from larva to adult worms in small intestine and remain there till they die. In mild ascariasis, symptoms are mild abdominal pain, nausea and vomitting or diarrhoea with blood stool.
In severe infection, large number of worms are present in a person which may cause severe abdominal pain, fatigue, vomitting and weight loss.

2. If lungs are infected After ingestion of Ascaris eggs, these hatch into larvae in small intestine. These larvae migrate into lungs via blood or lymph. At this stage, symptoms are similar to asthma or pneumonia with cough, breathlessness and wheezing. After 6-10 days in lungs, larvae travel into throat where these are coughed up and swallowed.

Question 11.
(i) What is immunity?
(ii) Give an account of cell-mediated immunity.
Answer:
(i) Immunity is the capactiy of an organism to resist or defend itself from the development of a disease. It has two main types, i.e. innate immunity and acquired immunity.

(ii) Immune response is the specific reactivity induced in a host by an antigentic stimulus. The immune response is of following types
• Humoral Antibody Mediated Immunity (AMI)
• Cell-Mediated Immunity (CMI)

Cell-Mediated Immunity:
It is the responsibility of a sub-group of T-cell, called T-cytotoxic cells. An activated T-cytotoxic cell is specific to a target cell which has been infected and kills the target cell by a variety of mechanisms.

It prevents the completion of life cycle of the pathogen since it depends on an intact host cell. Cell mediated immunity is also invovled in killing of cancer cells. T-cells attack the following
(a) Cells that have become infected by a microorganism most commonly a virus.
(b) Transplanted organs and tissues.
(c) Cancer causing cells.
The whole cell is involved in the attack, so this type of immunityis described as cell-mediated immunity.
T-cells do not relase antibodies.

Question 12.
Write a short note on innate immunity.
Or What is innate immunity?
Answer:
Innate Immunity (Inborn)
It is the type of immunity which is present from birth and is inherited from the parents. That’s why it is also called as natural immunity. It is non-specific in nature as it involves general protective measures against any invasion. Innate immunity provides the early lines of defense against pathogens. The principal components of innate immunity that act as barrier system to prevent the entry of pathogens are given below
1. Mechanical barriers
2. Chemical barriers
3. Phagocytosis
4. Fever
5. Inflammation
6. Acute phase proteins
7. Natural Killer (NK) cells

1. Mechanical or Physical Barriers
They prevent entry of microorganisms in the body, e.g. skin, mucous coating of epithelium lining the respiratory, gastrointestinal and urogenital tracts. These barriers are also called as first line of defence.

• Skin It is outer and tough layer of epidermis that consists of insoluble protein called keratin. It prevents the entry of bacteria and viruses. The periodical sheding off process of skin removes any clinging pathogen.
• Mucous membrane The gastrointestinal tract, urinogenital tract and conjuctiva are lined by mucous membrane.

This membrane secretes mucus which entraps microbes, dust or any foreign particles and finally propelled them out through tears, saliva, coughing and sneezing.

2. Chemical or Physiological Barriers
It includes certain chemicals which dispose off the pathogens.
These are given below

1. Acid of stomach, kills the ingested microorganisms by secreting acid gastric secretion (pH 1.5 – 2.0).
2. Low pH of sebum (i.e. 3.0-5.0) forms a protective film over the skin that inhibits growth of many microbes.
3. Lysozyme is a hydrolytic enzyme present in all mucous secretions like tears, saliva and nasal secretions. It attacks bacteria and dissolves their cell walls.
4. Gastro and duodenal enzymes secrete proteases and lipases. These enzymes digest a variety of structural and chemical constituents of pathogens, e.g. gastric acids easily inactivate rhinoviruses.
5. Mothers milk Lactoferrin and neuraminic acid are antibacterial substances present in human milk to fight against Staphylococci.
6. A group of proteins produced by virus infected cells, i.e. interferons induces a generalised activated state in neighbouring uninfected cells.
7. Humans and some other animals secrete an number of antimicrobial peptides such as defensins. One micrometre thick biofilm of defensins protects the skin from microbial assault.

3. Phagocytosis
When pathogens or microbes penetrate the skin or mucous membrane certain cell types surge towards the site of infection. These can be neutrophils, monocytes and macrophages which engulf the pathogens to form a large intracellular vesicle called phagosome.

The phagosome fuses with lysosome to form phagolysosome. The secretion of lysosomal enzymes digests bacterial cells. The useful products remains in the cell while the waste is egested out of the cell. Therefore, these phagocytes are also known as second line of defence.

4. Fever
It may be brought about by endotoxins or proteins (cytokines) produce by pathogens called endogenous pyrogens.

When enough pyrogens are produced, then there is rise in temperature which strengthens the defence mechanism to inhibit the growth of microbes. Fever is a symptom of an internal diagnoses of the cause of infections.

5. Inflammation
It is a defensive response of the body to tissue damage.
It is characterised by abrasions, chemical irritations, . heat, swelling, redness and pain. Inflammation in a non-specific response of the body to injury. It is an attempt to dispose off microbes, toxins or foreign material at the site of injury by macrophages to prevent their spread to other tissues and to prepare the site for. tissue repair. Thus, it helps to restore tissue homeostasis.

Broken mast cells release histamine, bradykinin, etc., which cause dilation of capillaries and small blood vessels. As a result more blood flows in these areas making them red and warm. Therefore, the accumulation of this results into tissue swelling (oedema).

After few days, due to phagocytosis, a cavity containing necrotic tissue and dead bacteria is formed. This fluid mixture is called pus.

6. Acute Phase Proteins
The chemical messenger of immune cells called cytokines are important low molecular weight proteins. These heterogenous proteins stimulate or inhibit the differentiation, proliferation or function of immune cells and also certain viral infections.

7. Natural Killer Cells
These are non-phagocytic granular lymphocytes which are present in spleen, lymph nodes and bone marrow.

Question 13.
What are interferons?
Ans.
Interferons are antiviral glycoproteins released by the virus infected host cells. They do not inactivate to kill the virus but enter the neighbouring uninfected host cells to prevent viral multiplication in them.
Interferons are host specific as they are produced by one host and will not work in another host.

Q 14.
Mention the origin and importance of T-cells.
Ans.
T-cells or T-lymphocytes are originates in bone marrow in immature forms. In thymus, these cells are transformed into mature T-!ymphocytes.

There are four types of T-cells, i.e. helper T-cells, suppressor T-cells, memory T-cells and cytotoxic T-cells. Helper T-cells stimulate B-cells to produce antibodies and cytotoxic T-killer cells attack foreign cells.
Suppressor T-cells suppress the functions of cytotoxic and helper T-cells and memory cells recognise the original invading antigen to create a more intense immune response.

Question 15.
What are immunoglobins?
Or What is antibody?
Answer:
Humoral response or Antibody-Mediated Immunity (AMI):
It is mediated by antibodies present in blood and lymph. Immunoglobulins or antibodies are glycoproteins produced in the body by B-cells in response to an antigen, e.g. IgA. IgG, IgM, IgE and IgD.
B-cells multiple in large number and transform into larger cells called plasma cells or plasmocytes. The transformation into plasma cells in assisted By T-Helper cells (TH). These antibodies destroy antigens by specific antigen – antibody interaction.

Question 16.
Why is mother’s milk considered the most appropriate food for a newborn infant?
Answer:
Mother’s milk is considered most appropriate for a newborn infant as it provides immunity in the initial period of its life. The yellowish fluid colostrum secreted by mother during the initial days ofdactation has abundant antibodies (IgA) to protect the infant from primary infections like cold, flu, etc.

Question 17.
Write a short note on vaccination.
Answer:
Vaccination refers to the process of injecting a biological or chemical agent that enhances the immunity of a person against the specific disease. It generally involves injection of dead organisms into . host organism.
Vaccination is the best preventive measure against any disease. A number of specific vaccines are given against many disease, e.g. polio vaccine, diphtheria vaccine, etc.

Question 18.
Why are tumour cells dangerous?
Answer:
Tumour cells are dangerous due to the following reasons

• These grow rapidly and also damage normal cells.
• Cells from tumours can get sloughed off and may reach other parts of the body via blood and start a new tumour, i.e. metastasis.
• Tumour cells compete for nutrients and may starve the other cells.

Question 19.
Write a short note on types and causes of cancer.
Or Write short note on cancer.
Answer:
Causes of Cancer
The agents which cause cancer, are called carcinogens.
Cancer can be induced by either physical, chemical or
biological agents.

1. Physical agents These are ionising radiations like X-rays, v-rays and the non-ionising rays like UV-rays which can cause DNA damage leading to neoplastic transformation.
2. Chemical agents These are tobacco smoke, benzene fumes, arsenic, hormones and aflatoxin, etc.
3. Nutritional agents Deficiency of some nutrients like vitamins, minerals and proteins causes cancer.
4. Biological agents Many cancers are caused by viruses. The association of Hepatitis-B and primary liver cancer has been established.
5. Mechanical factors Trauma, irritation and severe friction have been identified to cause malignancy.
6. Host factors These include age, sex, marital status, race, socio-economic status, customs and habits of the host.
7. Environmental factors These include radiation, air pollution, diet, drugs and social environment.
8. Genetic factors All factors have a genetic basis and are caused by genetic transformations of cells.

Question 20.
What is HIV?
Answer:
The HIV name was given in 1986 to AIDS virus. The two more strains of HIV, namely HIV 1 and 2 have been discovered. HIV viruses have originated from non-primates from West-central Africa and transferred to human. HIV 1 is more pathogenic and distributed world-wide, while HIV 2 is less prevalent and less pathogenic. It is distributed in West Africa only.

Question 21.
How is the AIDS provirus formed?
Answer:
HIV first attaches to the host cell surface by adsorption. It then enters CD 4 cells and the HIV RNA changes to DNA (provirus). This HIV provirus gets inserted into DNA of CD \ cell and them begins to replicate using the host’s cellular.

Question 22.
How AIDS can be prevented?
Answer:
There is no effective treatment developed to treat AIDS. Therefore, some preventive measures are recommended to prevent its infection.
The preventive measures are as follows

1. Sterlise all surgical instruments before use.
2. The transfusion of blood should be subjected to HIV test.
3. Infected mother should avoid pregnancy otherwise, it may also transmit to child.
4. Heterosexual activites should be prohibited.
5. Motivate to use condoms during sexual activities.
6. Proper medical dispose off should be established.

Government of Indian launched national AIDS control board, national AIDS committee, national AIDS control organisation, etc., to create awareness among people about HIV transmission and progression of AIDS.

Question 23.
Write short note on drug abuse.
Answer:
Drug Abuse and Addiction:
Drugs are chemicals which are used in the treatment of a disease under the supervision of a physician. But prolonged unnecessary use of a drug makes a person dependent and an addict to that drug.

Question 24.
From which plant cocaine is obtained? Why sports persons are often known to abuse this drug?
Answer:
Cocaine is derived from the leaves and young branches of South American plant Erythroxylum coca or coca plant.
Sports persons abuse this drug because it is a strong stimulant and acts on central nervous system, producing a sense of increased energy. It is highly addictive.

Question 25.
Write the source and effects of following drugs.

1. Morphine
2. Cocaine
3. Marijuana

Answer:

1. Morphine It is obtained from latex of Papaver somniferum.
   It has a sedative effects that slows down the body function.
2. Cocaine is obtained from plant Erythroxylon coca. It affects central nervous system and produces increased sense of happiness.
3. Marijuana It is obtained from Cannabis sativa and affects cardiovascular system of the body.

Differentiate between the following (for complete chapter)

Question 1.
Congenital diseases and Acquired diseases.
Answer:
Differences between congenital diseases and acquired diseases are as follows

Congenital diseases	Acquired diseases
Diseases present from birth	Disease occurs only after birth.
These are occur due to gene or chromosomal mutations.	These are non-heritable but are caused due to some causative agents like bacteria, fungus, virus.
e.g. Down syndrome, haemophilic, etc.	e.g. leprosy, typhoid, malaria, etc.

Question 2.
Amoebiasis and Filariasis.
Answer:
Differences between amoebiasis and filariasis are as follows

Amoebiasis	Filariasis
Entamoeba histolytica is the causative organism of amoebiasis.	Filariasis is caused by filarial nematodes, Wuchereia bancrofti and W. malayi.
Houseflies are mechanical carriers and transmit the parasite from faeces of the infected person to food and contaminate them.	Filarial infectin is caused by different species of mosquitoes, e.g. Culex, Aedes, etc.
Symptoms include constipation, abdominal pain, cramps, etc.	Symptoms include oedema, swelling of lower exteremities and deformation of genital organs.

Question 3.
Primary immune response and Secondary immune response.
Answer:
Differences between primary immune response and secondary immune response are as follows

Primary immune response	Secondary immune response
It occurs as a result of the first contact of the individual with an antigen.	This immune response occurs during second and subsequent contacts with the same antigen.
Its response is feeble to moderate.	Its response is strong.
It takes a longer time to establish immunity.	It is rapid.
It declines rapidly.	It lasts longer, sometimes lifelong.
Receptors for the antigen develops during response.	Receptors are already present.

Question 4.
Active immunity and Passive immunity.
Answer:
Differences between active immunity and passive immunity are as follows

Active immunity	Passive immunity
Develops due to contact with pathogen or its antigen.	Develops when readymade antibodies are injected into the body.
Slow but long lasting.	Fast but lasts for few days.
No or few side effects.	May cause side effects.

Question 5.
Antibody-mediated immune system and Cell- mediated immune system.
Answer:
Differences between antibody mediated immune system and cell-mediated immune system are as follows

Antibody-mediated immune system	Cell-mediated immune system
It is mediated by B-lymphocytes.	It consists of T-lymphocytes.
It operates through formation of antibodies.	It operates directly through T-cells.
It acts on pathogens that invade body fluids.	It operates against those pathogens which invade body cells.
It hardly has any effect against cancers and transplants.	It operates against cancer cells and transplants.

Question 6.
B-lymphocytes and T-lymphocytes.
Answer:
Differences between B-lymphocytes and T-lymphocytes are as follows

B-iymphocytes	T-lymphocytes
B-cells form humoral or Antibody Mediated Immune System (AMIS)	T-cells form Cell-Mediated Immune System (CMIS),
They defend against viruses and bacteria that enter the blood and lymph.	They defend against pathogens including protists and fungi that enter the cells.
They form plasma cells and memory cells by the division.	They form killer, helper and suppressor cells by the division of lymphoblasts.

Question 7.
Antigens and Antibodies.
Answer:
Differences between antigens and antibodies are as follows

Antigens (Immunogens)	Antibodies (Immunoglobins)
They are usually foreign materials such as a protein or polysaccharide molecules.	These are protein molecules.
These trigger the formation of antibodies.	These are synthesised in the body to combat foreign materials.
These may occur on the surface of microbes or as free molecules.	These may occur on the surface of plasma cells and in body fluids.
Antigens bind to macrophages to reach helper T-cells to initiate immune response.	These directly join antigens to destroy them.
They produce diseases or allergic reactions.	These are protective and immobilise or lyse antigenic molecules.

Question 8.
IgG and IgM.
Answer:
Differences between IgG and IgM are as follows

IgG	IgM
It is the most abundant Immunoglobulin in blood.	It is third abundant immunoglobulin in blood.
IgM is replaced by IgG and becomes the principal antibody.	It is first antibody synthesised by the newborn.
It is monomer.	It is pentamer.

Question 9.
Cancer cells and Normal cells.
Answer:
Differences between cancer cells and normal cells are as follows

Cancer cells	Normal cells
The lifespan is not definite.	These cells have a definite lifespan.
These ceils divide in an unregulated and uncontrolled manner.	These cells divide in a regulated manner.
These cells do not have contact inhibition.	The cells show contact inhibition.
These cells do not undergo differentiation.	These cells undergo- differentiation.
These cells do not remain adhered and have lost cell to cell contact.	These cells remain adhered, i.e. have cell to to cell contact.

Question 10.
Stimulants and Hallucinogens.
Answer:
Differences between stimulants and hallucinogens are as follows

Stimulants	Hallucinogens
These increase the activity of CNS.	These damage the CNS performance.
These induce alterness, more wakefulness and excitement	These change thought of a person, feeling and perceptions, cause hallucinations.
e.g. caffeine, cocaine, amphitamines.	e.g. charas, ganja, bhang and marijuana.