Nutrition and Health - 2 (Class - IX)

Community is composed of individuals. If all the individuals have good personal health, the entire community will be healthy. Also, if the community is having hygienic surroundings, the individual health will be good. Thus, the two are interdependent, i.e. they depend on each other. The terms ‘overdependent’, ‘independent’ and ‘intradependent’ are not correct for this interdependent relation.

During any accident, wounds occur and they are exposed to air and soil. The air and soil may contain tetanus-causing microbes. Hence, the person is immediately given anti-tetanus injection. 

Drinking milk will have no bad effect on the health as it is a source of almost all nutrients and it is recommended for good health.

A person will be healthy if he eats a proper diet (option 3), lives in a hygienic environment (option 4) and keeps his body fit by exercising regularly (option 1). Thus, options (1), (3) and (4) help a person to be healthy as these habits keep the germs away and thus, reduce the chances of getting infected by diseases. But, drinking alcohol is not a healthy practice as it adversely affects the nervous system and its prolonged consumption adversely affects the liver and general body health. Thus, (2) is the correct answer because drinking alcohol is responsible for the ill health of a person.

Vaccines are 'preventive', i.e. they help us in fighting against a disease before it is actually caused. The only option that suits this fact is (3). On the contrary, options (1) and (2) are related to treatments, i.e. cure after the host is infected. This is done by using suitable medicines and drugs. Hence, options (1), (2) and (4) are incorrect.

Bacterial diseases are those diseases that are caused and transmitted by different bacteria. Typhoid, cholera and tuberculosis are caused by bacteria namely Salmonella typhii, Vibrio cholera and Bacillus calmettie, respectively. Dengue fever is caused by a virus, which is transmitted by the vector Aedes mosquito. Hence, option (3) is the correct answer.

Common cold (usually caused by viruses) is an infection of the upper respiratory tract. Signs and symptoms include coughing, sore throat, runny nose, sneezing and fever which usually resolve in seven to ten days, with some symptoms lasting up to three weeks. 

Headache, diarrhoea and common cold last for some time and affect us severely for that short period. But they do not leave any of the effects like weakness. Thus, these are acute diseases.
On the contrary, tuberculosis is chronic because it affects us for a long time and also makes the body weak, even after the infection is cured. It is caused due to bacteria and in this disease, the lungs and the respiratory system are affected. In this, mucus begins to collect in lungs, gradually leading to inefficient gaseous exchange, frequent cough and even bleeding in the throat at later stages. Hence, option (4) is the correct answer.

An active immune system recruits many cells to the affected tissue to kill off the disease-causing microbes. This recruitment process is called inflammation.

(a) Acute diseases: These diseases are severe, but short-spanned and get less time to cause prolonged poor health.
(b) Chronic diseases: These diseases last for longer periods of time and take sufficient time to affect different parts of the body and lead to a poor health, which recovers after a long time.
(c) Infectious diseases: These diseases spread from a diseased person to a healthy person due to the transmission of disease-causing organisms (for example, common cold).
(d) Non-infectious diseases: These diseases do not spread from one person to another. For example, heart ailment, cancer, etc. They are not caused by infectious agents. The causative agents of these diseases are internal factors. 

All of the above mentioned products are used as milk adulterants in India. They decrease the quality of milk and make it harmful for the consumption of humans.

 Metanil yellow is a common adulterant of lentil. It is toxic in nature and has adverse effects on the liver, intestine and brain.

The adulterant added to dal is metanil yellow. Its presence can be tested in dal by adding a few drops of HCl to a test sample. If the solution turns pink in colour, it indicates the presence of metanil yellow.

This is the correct option. The symptoms of scurvy are bleeding of gums and swelling of joints. The symptoms of rickets are weak bones and decaying teeth. The symptom of haemorrhage is that the clotting of blood is affected.

Brittle bones are associated with calcium deficiency. They become prone to fractures.