FRANK Solutions for Class 9 Biology Chapter 20 - Health: Causes of Diseases

Chapter 20 - Health: Causes of Diseases Exercise 191

Question 1

Define the following:
(a) Disease
(b) Pathogen
(c) Infection
(d) Incubation period

Solution 1

(a) Disease is the stage when body or any part of it shows some disturbance in normal functions.
(b) Pathogen refers to any disease causing organism.
(c) Infection refers to the pathological state resulting from the invasion of the body by pathogenic microorganisms.
(d) Incubation period refers to the period between exposure to an infection and the appearance of the first symptoms.

Chapter 20 - Health: Causes of Diseases Exercise 192

Question 1

Write the full forms of AIDS. Name the causative germ. How is this disease transmitted?

Solution 1

Full form of AIDS is Acquired Immuno Deficiency Syndrome.
It is caused by Human Immunodeficiency virus (HIV)
AIDS is transmitted in the following ways:
(i) Sexual intercourse with the suffering from AIDS.
(ii) Transfusion of the AIDS infected blood.
(iii) New born child born from the infected mother.

Question 2

Solution 2

Degenerative diseases - Rheumatic
Diabetes - Insulin
AIDS - HIV virus
Cholera - Bacterial disease
Influenza - Viral disease
Mosquito - Vector
Elephantiasis - Filaria

Question 3

Fill in the blanks:
(a) A reaction caused by the body to some foreign is called ______.
(b) The causative agent of malaria is a _______.
(c) Small pox is caused by ______ whereas diphtheria is caused by ______.
(d) Rabies is a disease ______.
(e) Filariasis is caused by ______.

Solution 3

(a) allergy
(b) Plasmodium
(c) virus, bacteria
(d) caused by virus
(e) Wuchereria bancrofti

Question 4

Differentiate between the following pairs:
(a) Endemic and Pandemic disease.
(b) Sporodic and Epidemic disease.
(c) Infectious and non-infectious disease.
(d) Congenital and Acquired disease.

Solution 4

Question 5

Answer the following:
(a) Three diseases caused by bacteria.
(b) The category of germs which causes rabies, small pox and mumps.
(c) Name of the disease spread by dog.
(d) Two diseases caused by parasitic worms.
(e) Any two degenerative diseases.

Solution 5

(a) Typhoid, cholera, tetanus
(b) Viruses
(c) Rabies
(d) Filariasis, Ascariasis
(e) Arthritis, diabetes

Question 6

State whether the following statements are True or False:
(a) Anopheles mosquito spread elephantiasis marked by swelling of lower limbs.
(b) Gonorrhoea is a disease which is caused which is caused by bacterium tryponema palladium.
(c) Allergy is due to hypersentiveness of tissue to certain substances.
(d) Goitre is endemic in sub-himalayan region of India.
(e) AIDS is caused by bacteria.
(f) Plague is epidemic disease.

Solution 6

(a) False
(b) False
(c) True
(d) True
(e) False
(f) True

Question 7

Each question has four options. Choose the correct answer:
(i) Which one of the following is a hormonal disease?
(a) Diabetes
(b) Haemophilia
(c) Allergy
(d) Scurvy
(ii) Dehydration results from
(a) pneumonia
(b) measles
(c) rabies
(d) cholera
(iii) Elephantiasis is caused by
(a) Entamoeba
(b) filaria
(c) Aspergillus
(d) rabied dog
(iv) Which of the following diseases has been eradicated?
(a) Plague
(b) Small pox
(c) Poliomyelities
(d) kala-azar
(v) A viral disease is
(a) Cancer
(b) leukaemia
(c) Typhoid
(d) yellow fever
(vi) Cancer is
(a) Non-malignant tumour
(b) controlled division of cells
(c) Uncontrolled division of cells
(d) viral infection

Solution 7

(i) (a) Diabetes
(ii) (d) Cholera
(iii) (b) filarial
(iv) (b) Smallpox
(v) (d) yellow fever
(vi) (c) Uncontrolled division of cells

Question 8

Write short notes on the following:
(a) Communicable diseases
(b) Non-communicable diseases
(c) Epidemic diseases
(d) Sporadic diseases.

Solution 8

(a) Communicable diseases are the diseases which spread by different organisms such as bacteria, virus and fungi. These are transmitted from one person to another. Example - Flu, malaria, syphilis.
(b) Non-communicable diseases - These diseases are not transferred from one person to another. They are of different types like allergy, nutritional deficiencies, degenerated diseases, cancer and mental diseases. Example - Arthritis, hypertension
(c) Epidemic diseases - These diseases spread rapidly and affect a large number of people at a time. Example - Spread of plague in Surat in 1994.
(d) Sporadic diseases - This refers to a type when there are scattered individual cases of a disease.

Question 9

Name three bacterial diseases with their causal organisms.

Solution 9

Pneumonia - Diplococcus pneumonia
Tetanus - Clostridium tetani
Whooping cough - Haemophilus pertussis

Question 10

Name any two human diseases caused by viruses. Give their symptoms and methods of treatment.

Solution 10

(i) Influenza -
Symptoms - Symptoms begin with headache, cold, sneezing, nose clogging, pain in hands, feet and waist. Watery discharge from nose and eyes makes patient restless and weak.
Method of treatment - Increased immunity is the best remedy. Penicillin, streptopenicillin and gamma globulin lower the effect of this disease. Eucalyptus oil should be applied on nose. During high fever, ice fermenting should be done as well as liquid food given.
(ii) Polio -
Symptoms - Symptoms commence 7-12 days after infection. These include infection of throat and intestines, muscle stiffness in neck and back.
Treatment - Vaccine of polio is more effective in children. Oral polio drops are also given to children.

Question 11

What do you understand by infectious disease? Discuss any one disease.

Solution 11

Infectious diseases are the diseases which spread by different organisms such as bacteria, virus and fungi. These are transmitted from one person to another.
Influenza is a highly infectious viral disease. This disease spreads quickly from one person to the next. The virus is transmitted from the patient to the other person while the patient is coughing, sneezing, laughing or speaking. This is also transmitted by contaminated towel and handkerchief.
Symptoms - Symptoms begin with headache, cold, sneezing, nose clogging, pain in hands, feet and waist. Watery discharge from nose and eyes makes patient restless and weak.
Method of treatment - Increased immunity is the best remedy. Penicillin, streptopenicillin and gamma globulin lower the effect of this disease. Eucalyptus oil should be applied on nose. During high fever, ice fermenting should be done as well as liquid food given.

Question 12

Write a brief account on the following diseases:
(a) Tuberculosis
(b) Diphtheria
(c) Influenza
(d) Measles
(e) Malaria
(f) Filaria.

Solution 12

(a) Tuberculosis: It is caused by Mycobacterium tuberculosis. It affects bones, intestine, brain and other organs. Symptoms include restlessness in the beginning, loss of appetite, pain in chest and increase in heart beat. Treatment includes taking medicines like P.A.S. and thioacetazone.
(b) Diptheria: It is a communicable disease caused by Corynebacterium diptheriae. In most of the people, this is caused by droplet infection, coughing and spitting. Symptoms are high fever, weakness and swelling in the throat. Patients should be treated with anti-toxin injection. Children should be vaccinated with DPT.
(c) Influenza: Influenza is a highly infectious viral disease. This disease spreads quickly from one person to the next. The virus is transmitted from the patient to the other person while the patient is coughing, sneezing, laughing or speaking. This is also transmitted by contaminated towel and handkerchief.
Symptoms - Symptoms begin with headache, cold, sneezing, nose clogging, pain in hands, feet and waist. Watery discharge from nose and eyes makes patient restless and weak.
Method of treatment - Increased immunity is the best remedy. Penicillin, streptopenicillin and gamma globulin lower the effect of this disease. Eucalyptus oil should be applied on nose. During high fever, ice fermenting should be done as well as liquid food given.
(d) Measles: It is a highly infectious viral disease. It usually affects children. Symptoms include - suddenly high fever, red eyes and oozing of water from eyes. Fever, cough and rashes appear on the third day. After 2 to 3 days temperature goes down. Treatment includes complete rest, clothes and towels should be washed in boiling water. Endomonstan B-vaccine is the best treatment.
(e) Malaria: This disease is caused by parasitic protozoa, Plasmodium. The disease is transmitted from one person to another by female anopheles mosquitoes. The symptoms are followed by high fever, temperature rises on alternate days. Sweating is followed by lowering of body temperature. Besides this patient feels headache, nausea and vomit.
This disease is treated by medicines like chloroquine, deraprin, etc.
(f) Filaria: It is caused by filarial worm, Wuchereria bancrofti. This disease is transmitted by mosquito. Symptoms include - irritation, blockage of lymphatic ducts and fever. This disease can be treated with an arsenic medicine for adult worms.

Question 13

What are the symptoms of diabetes insipidus?

Solution 13

The symptoms of diabetes insipidus are:
(i) Excessive urination, but urine does not contain sugar at all
(ii) Increased frequency in urination
(iii) Progressive weakness
(iv) Increased appetite
(v) Loss of weight
(vi) Excessive thirst

Question 14

List various organisms (atleast 5) which cause human disease.

Solution 14

Diplococcus pneumonia, Clostridium tetani, Ascaris lumbricoides, Plasmodium species, HIV virus

Question 15

What are the main causes of human heart diseases?

Solution 15

The main causes of human heart diseases are:
(i) Body overweight
(ii) Birth defects of the heart
(iii) Deposition of cholesterol resulting in arteriosclerosis
(iv) Severe infections
(v) Excessive use of coffee, tobacco etc.
(vi) Malfunctioning of some of the endocrine glands