Food is composed of components that give mixed sensations called taste. It is perceived by the taste buds, tiny wart-like bumps, present on the tongue. A person has around three thousand taste buds. The taste buds have numerous sensory cells that are renewed once a week. The four major taste sensations are sweet, salty, bitter […]
Haemoglobin is an iron-containing protein present in the blood. It carries oxygen from the lungs to the body tissues and then, carbon dioxide back from these tissues to the lungs. The iron in haemoglobin imparts red colour to blood. The normal range for haemoglobin is 12-16 gm/dL for females and 14-18 gm/dL for males. A
Polio is a condition in which a person is unable to walk properly. Other names for polio are infantile paralysis or acute poliomyelitis. It is a highly contagious viral disease, caused by poliovirus infection. It affects a human*s nervous system. The polio virus enters the body and travels to the spinal cord, and brain through
Invisible forms of life, called germs, are present in the air, soil, food and also in water. Many of them cause diseases or infections. The human body has an ability to fight the attack of germs naturally. This ability to fight is called immunity. Immunity can be categorised into innate immunity and acquired immunity. Innate
An antibody is a substance that is produced by our body to fight poisons or toxic foreign substances (antigens) which enter the body. They are protective proteins produced by the immune system. Their production begins when any foreign substance attacks our body and continues until all antigen molecules are removed. They provide immunity to the
Our mind stores and remembers things. This act of remembering something is called memory. In other words, the ability to remember past events, facts, habits, and skills is called memory. Memory has two components: short-term and long-term memory. Short-term memory lasts about 20-30 seconds at a time while long-term memory lasts for a long time.
Vitamins are an important group of substances found in food. The word ‘vita’ means life. They are necessary for healthy life. Our body needs them in tiny quantities to continue the vital processes of the body. Vitamins are either water-soluble or fat-soluble. Vitamins are named as A, B, C, D, etc. Vitamin A is found
Skin is the outer covering on the bodies of animals or human beings. It protects muscles, bones and the internal organs. As it is in direct contact with the environment, it protects the body from viruses, parasites, etc. Other functions of the skin are insulation, temperature regulation and sensation. It also supports the production of
Hallucinations are imaginary sensations created by the mind. They appear real. In this situation, people imagine some imaginary situations like, they see a person, an animal, or a thing that is not there. Sometimes, it can relate with imaginary tastes as well. Some of the common reasons for hallucinations are lack of sleep, mental illness,
Shock is a condition of sorrow. In this condition the circulatory system fails to supply sufficient blood to tissues. It can be a life-threatening condition. Shock may result from trauma, heatstroke, blood loss, an allergic reaction, or other causes. Symptoms of shock can begin with restlessness and may even lead to unconsciousness. When the body
Blood pressure (BP) is the measure of the force with which the heart pumps blood in the body. It is measured with the help of the BP meter. It measures two types of pressure: systolic and diastolic. Systolic blood pressure is exerted by blood on artery walls when the heart contracts and pumps blood. Diastolic
A vaccine provides immunity against a particular disease or similar diseases. The immune system of the body is stimulated by it. It helps the immune system to remember and recognise disease-causing agents and protects the body from attacks in future. Vaccines may be given through injections, orally by mouth or using an aerosol. Some of
A ‘cold’, also called common cold, is a viral infection that attacks the upper respiratory tract. It is the most frequent infectious disease in humans. It affects the nose and the throat. During this infection, the mucous membrane of the nose and the throat becomes inflamed. The body’s immune response to the infection leads to
Humans are one of the species who laugh. Laughter is a sense of feeling good, happy and joyful. It is a response to humour, comprising two parts, gestures and production of sound. A hearty laugh triggers changes in the various parts of the body like arm, leg and trunk muscles. Fifteen facial muscles contract when
The lacrimal system is responsible for producing and secreting tears. It is situated near the eyeball. A person sheds three types of tears that are basal tears that keep the cornea nourished and lubricated; reflex tears, which help to wash out any irritant in the eyes from foreign particles like onions, and psychic or crying