$$ \text { Drugs and alcohol give short-term 'high' and long-term 'damages'. } $$
Curiosity, need for adventure and excitement and experimentation, constitute common causes, which motivate youngsters towards drug and alcohol use.
The frequent use of drugs/alcohols drive people to take them even when these are not needed, or even their use becomes self-destructive.
Short-term effects of drugs/alcohols
A relaxing effect
Lowered inhibitions
Slow reflexes
Reduced coordination
Reduced tension
Poor concentration
Slow reaction time
Slower brain activity
Sensations and perceptions that are less clear
Long-term effects of drugs/alcohols
Disrupts normal brain development
Liver damage and cirrhosis of the liver
Brain cells die, decreasing brain mass
Stomach and intestinal ulcers and destroyed organs
Blood pressure increases, causing heart disease, heart attack or stroke
Male sperm production decreases
Lower levels of iron and vitamin-B, causing anaemia
Alcoholism
Death and
Fetal alcohol syndrome in unborn children
Diseases like dysentery, cholera, typhoid, etc., are more common in over crowded human settlements. Why?
Dysentery, cholera and typhoid are more common in crowded settlements because these are infectious diseases and spread from person to person contact. Water gets contaminated with the excreta of infected people and causes the spread of infection to other people.
From which plant cannabiniods are obtained? Name any two cannabinoids. Which part of the body is effected by consuming these substances?
Cannabinoids are obtained from the inflorescence of the plant Cannabis sativa. Marijuana, hashish, charas, ganja are some cannabinoids. These chemicals interact with cannabinoid receptors of the body, mainly present in the brain. Cardiovascular system of the body is effected adversly by consuming these substances.
In the metropolitan cities of India, many children are suffering from allergy/asthma. What are the main causes of this problem. Give some symptoms of allergic reactions.
In metropolitan cities life style is responsible in lowering of immunity and sensitivity to allergens. More polluted environment like dust in surroundings increases the chances of allergy in children. Some symptoms of allergic reactions are sneezing, watery eyes, running nose and difficulty in breathing.
What is the basic principle of vaccination? How do vaccines prevent microbial infections? Name the organism from which hepatitis-B vaccine is produced.
The principle of vaccination is based on the property of 'memory' of immune system.
In vaccination, a preparation of antigenic proteins or inactivated/live but weakened pathogens is introduced into the body. The antigens generate primary immune response by producing antibodies along with memory B-cells and T-cells.
When the vaccinated person is attacked by the same pathogens, the existing memory B-cells and T-cells recognise the antigen and overwhelm the invaders with massive production of lymphocytes and antibodies.
Hepatitis-B vaccine is produced from yeast.