Progress Check 1
Fill in the blanks.
(a) Cleanliness, rest and sleep, and physical exercise are a part of ............... hygiene.
(b) One must always breathe by the ............... and never by the ............... .
(c) Fresh air brings ............... into the living rooms.
(d) One must never put a sharp pointed object into the ..............., it may rupture the ............... .
(e) For adults 6-7 hours of continuous undisturbed ............... is sufficient.
(f) The municipal bodies must ensure the supply of clean germ-free ............... and an efficient ............... disposal.
(a) Cleanliness, rest and sleep, and physical exercise are a part of personal hygiene.
(b) One must always breathe by the nose and never by the mouth.
(c) Fresh air brings Oxygen into the living rooms.
(d) One must never put a sharp pointed object into the ear it may rupture the ear drum.
(e) For adults 6-7 hours of continuous undisturbed sleep is sufficient.
(f) The municipal bodies must ensure the supply of clean germ-free drinking water and an efficient sewage disposal.
List any three advantages of a daily bath.
Three advantages of a daily bath are:
- Keeps the skin clean and free of germs.
- Opens the sweat pores.
- Removes the body odour.
Progress Check 2
Tick-mark the correctly matched pairs of certain animals and their related diseases/habits.
- Culex — yellow fever
- Aedes — filariasis
- Anopheles — malaria
- Gambusia — eat up mosquito larvae
- Rat flea — diarrhoea
- Cockroaches — breed in man-holes
The correct pairs are:
- Anopheles — malaria
- Gambusia — eat up mosquito larvae
- Cockroaches — breed in man-holes
Progress Check 3
Mention if the following statements are True (T) or False (F)
- Contamination means entry of germs by insect bite.
- Sewage is the commonest source of contamination of water in the cities.
- Cholera is marked by acute diarrhoea and no urination.
- Typhoid is caused by a type of worm.
- Mosquitoes are the source of dysentery germs.
Corrected Statement — Contamination means entry of germs to food and water by flies.
Corrected Statement — Typhoid is caused by a type of bacteria.
Corrected Statement — Flies are the source of dysentery germs.
Multiple Choice Type
No urination due to shortage of water in the body is a typical symptom of
Reason — Cholera results in severe diarrhoea which further results in dehydration. Therefore, it results in no urination.
Which one of the following is an unhealthy habit?
- Removing wax from inside the ears
- Keeping the mouth closed while breathing
- Sleeping for only 6-7 hours
- Sharing towels with others
Sharing towels with others
Reason — Sharing towels with others can spread germs and diseases.
The protozoan that causes malaria is:
- Entamoeba histolytica
Reason — Malaria is caused due to Plasmodium.
The chemical substance mainly responsible for tooth disorders is
Reason — Excess fluorides affect teeth development and cause white streaks on enamel.
Typhoid is caused by
- None of the above
Reason — Typhoid is caused by Salmonella bacteria.
The germ causing Hepatitis is transmitted through:
- The bite of a mosquito
- Contamination of food by a housefly
- Personal contact with a patient
- Contaminated water
Reason — Hepatitis A is caused due to contaminated water.
Which of the following is an agent that acts as an intermediate carrier of a pathogen?
- None of these
Reason — The carrier of the pathogen is called vector. It transmits the pathogen to human beings and animals and cause diseases.
Which of the following is an insecticide
Reason — DDT was used as an insecticide. It is banned now due to its adverse environmental effects and human health risks.
Plasmodium is a :
Reason — The malaria germ Plasmodium is a Protozoan.
The fishes which selectively devour mosquito larvae are :
Reason — Gambusia is one of the biological control of mosquitoes.
Very Short Answer Type
Fill in the blanks:
(a) Taking stimulants and ............... are unhealthy habits.
(b) Physical exercise should be ............... and regular.
(c) Public drains and garbage must be covered with ............... powder or lime.
(d) ............... is often designated as public enemy no. 1.
(e) ............... is a parasite which lives on rat's skin.
(a) Taking stimulants and sedatives are unhealthy habits.
(b) Physical exercise should be systematic and regular.
(c) Public drains and garbage must be covered with bleaching powder or lime.
(d) Housefly is often designated as public enemy no. 1.
(e) Rat-flea is a parasite which lives on rat's skin.
Name the following :
(a) The bacterium which causes cholera.
(b) The liquid domestic wastes from the kitchen, toilet, etc.
(c) The chemical substances used to kill rats.
(d) The disease caused due to the inflammation of liver.
(e) The disease caused due to the bacilli bacteria released in tannery wastes from leather industries.
(a) Vibrio cholera
(c) Rat poison or raticides
Complete the blanks in the table given below:
|Dengue & yellow fever||Virus||Aedes mosquito|
Short Answer Type
(a) Health is the condition of the body of a person who depicts or portrays physical, mental, social and emotional fitness.
(b) Hygiene is defined as the science and practice of maintaining good health. It requires caring of one's own body (personal hygiene) and taking proper care of surroundings (social hygiene).
(c) The disease causing organisms are called pathogens or germs.
(d) Vector is any agent that acts as an intermediate carrier of a pathogen.
(e) Contamination means unwanted entry of disease causing germs into drinking water or edible foods.
Give suitable explanations for the following:
(i) One should breathe by nose and never by mouth.
(ii) Hands must be washed before eating food.
(iii) Eating places must be kept free of flies.
(i) One should breathe by nose and never by mouth because nose contains hair and mucous to trap dust and micro-organisms, so that the inhaled air becomes pure and the respiratory passage is free of dust and micro-organisms.
(ii) Washing hands before eating food is essential because our hands come into contact with various objects and surfaces throughout the day, many of which can carry harmful germs. These germs which may be picked up by our fingers and transferred to other parts of our body or into the mouth through food. Thus, washing hands helps protect us from diseases that can be transmitted through these germs or vectors.
(iii) Flies contaminate our food in various ways like by sitting on it, pouring out its saliva on it, depositing its excreta on the food while it feeds and so on. Hence, to avoid contamination of food and prevent the spread of diseases, eating places must be kept free of flies.
How are cockroaches and rats harmful to humans?
Cockroaches and rats are common household pests. They are harmful to humans in the following ways:
- Cockroaches eat and spoil food, paper and clothes. They are also suspected to be carriers of certain viral diseases, possibly including a cancer-causing virus.
- Rats eat grains and other foods. They also spread germs of certain diseases. Rat-fleas is a parasite that lives on rat's skin. It may carry germs of plague.
Name the two types of dysentery and their causative germs and give one main precaution against them.
The table below depicts the two types of dysentery, their causatives and precautions:
|Type of Dysentery||Causative||Precaution|
|Bacillary||Bacterium – Shigella||Consume safe(boiled) drinking water.|
|Amoebic||Protozoan – Entamoeba histolytica||Always check for food and water contamination before consumption.|
Mention three symptoms of the disease Hepatitis.
The three symptoms of Hepatitis disease are:
- Body ache
- Eyes turn yellowish, due to the bile pigments – urine turns to deep yellow
- Enlarged liver
Suggest any two methods of controlling flies.
The two methods of controlling flies are:
- Elimination of breeding places of flies.
- Spraying houses and breeding places of flies with insecticides.
List any three effective methods for controlling mosquitoes.
The effective methods for controlling mosquitoes are:
- Elimination of breeding places for mosquitoes.
- Spraying on stagnant water with Kerosene or some other greasy oil to kill larvae and pupae. Spraying DDT and other insecticides to kill adult mosquitoes.
- Biological control by introducing certain fishes like Gambusia which selectively devour on mosquito larvae.
Mention any three ways by which potable water can be contaminated.
Contamination of potable (drinking) water can occur in several ways such as:
- Sewage, if improperly disposed, leaks into sub soil and may contaminate underground water supplies.
- Urination and defecation near water bodies such as ponds, lakes and rivers
- Contamination of water bodies by the drainage of animal washings and wastes from poultries and dairies.
Long Answer Type
Describe the different ways by which the housefly contaminates our food.
The manner in which the housefly spreads diseases are:
- Hairy body and legs pick up the filth — Houseflies have spiny or hairy legs and body that tend to pick up dirt containing germs from germ-infested places such as faecal matter, rotten material, infected wound. When the housefly rests on our food, it rub its legs continuously dropping the particles of filth on the food, causing it to get contaminated.
- Pouring out saliva — Food is also contaminated with germs when the housefly moistens the foodstuffs by pouring out its saliva on it, or when it vomits (regurgitates) food which it has swallowed from dirty places.
- Excreta — It deposits its excreta while it feeds and thus contaminates human food.
What are the four major aspects of personal hygiene?
The four major aspects of personal hygiene are:
- Cleanliness — Regular washing of hands is very important for our health as it helps to avoid so many communicable diseases. Cleanliness also include daily bathing, wearing washed clothes and washing hair and eyes. Brushing teeth, twice daily helps to maintain oral hygiene.
- Rest and sleep — All organs of our body including the brain need rest. In general, the body obtains adequate rest by means of sleep. For adults 6-7 hours of continuous undisturbed sleep is sufficient.
- Physical exercise — Physical exercise are important for all age groups. It should be systematic and regular. It improves blood circulation and maintains general health.
- Healthy habits — Few healthy habits are:
- going to bed early but not immediately after dinner.
- bowel clearing daily morning
- tobacco, alcohol, stimulants and sedatives should be avoided.
- rooms should be well ventilated for fresh air and sunlight.
Structured / Application / Skill Type
The figure given below represents an organism. Study the same and answer the following question:
(a) Identify the organism and write its scientific name.
(b) Is it a causative agent of any disease? If yes, name the disease.
(c) Label the guidelines 1, 2 and 3.
(d) Is it a unicellular or a multicellular organism ? Mention the specific category of organisms to which it belongs.
(e) Write one important function of the part numbered 1.
(a) The organism is amoeba. Its scientific name is Entamoeba histolytica.
(b) Yes, it is the causative agent of Amoebic dysentery.
(c) The labelled parts are :
- 1 → Pseudopodium
- 2 → Nucleus
- 3 → Blood cell
(d) It is unicellular organism belonging to protozoan group of kingdom Protista.
(e) Pseudopodia helps in locomotion and ingestion (by formation of food vacuole).