body+worksheet

BLOOD Blood flows in our body in pipes called bloodvessels. There are 2 types of blood vessels, arteries and veins. Arteries carry oxygenated blood (except pulmonary artery and umbilical artery).Veins carry deoxygenated blood (except pulmonary and umbilical vein). Capillary is the smallest of a body's blood vessel and are part of the microcirculation. It is thinner than a strand of a hair. Blood is made of red blood cell(caries oxygen to the body), white blood cell(fights the germs), platelets(helps in the clotting of the blood) and plasma(in which all these components remain suspended). Blood is red because of the presence of hemoglobin (protein bounded iron, to carry oxygen. so when iron attaches with oxygen it turns red). Blood transfusion can save lives, so donate blood. When one donates blood, blood is produced by the bone marrow. Donated blood is stored in blood banks.AB is the universal recipient and O is the universal donor. The doctor who checks our blood is called pathologist. Malaria and AIDS are the diseases that are spread through blood. Some animals have blue colour blood (because of presence of haemocyanin) and others have white. Radiations cause suppression of bone marrow thereby decreasing its production leading to severe health problems. In carbon monoxide poisoning carbon monoxide irreversibly binds to hemoglobin to form [|carboxyhemoglobin], so that less hemoglobin is free to bind oxygen, and less oxygen can be transported in the blood causing irreversible damage to the body and thereby suffocation and may be death.

Bones Bones are inside our body. It gives support and forms the frame work of our body. Bones also protect the soft organs of our body. Ribcage protects the heart and lungs, skull protects the brain, and vertebral column protects the spinal cord. We grow because our bones are growing. Bones lots of calcium to grow. Food rich in calcium are milk and milk products. Baby is born with nearly 300 bones but an adult has 206 bones. (because they fuse together) Longest bone is femur (in the thigh) and the smallest bone is the stirrup (in the middle ear). Fracture is the breakage in the alignment of the bone. Exoskeleton creatures are crab and snail. Boneless creature are slug and starfish. Osteoporosis is the disease of bone in which mineral density is reduced. Doctor of the bones is called orthopedic. Also told them about osteoarthritis, palaentologist and fossils.

Teeth A baby is not born with teeth, but by the age of around 6months. First 2 incisors are visible. This set of teeth which gradually emerges is called milk teeth. There are 20 milk teeth. A milk tooth starts to fall off around 7 years of age, which are replaced by permanent teeth. If one does not take care of these teeth then u will have to visit a dentist for new teeth. Doctor who takes care of our teeth is called a dentist. STOP bottle feeding at night, if u want a healthy set of milk teeth. Teeth not only help to cut and chew the food but also help in speech. Sweets ,colas and smoking harms our tooth. Flossing, brushing, eating calcium rich food and also crunching a fruit keeps them healthy. Roots of the teeth are embedded in the jaw whereas the crown is visible. Crown is made up of enamel, dentine and pulp. Pain is felt ,when the decay reaches the pulp as there is presence of nerves. Halitosis is the bad breath from the mouth which could be because of poor oral hygiene or less intake of water. Herbivores have strong molars and premolars whereas the carnivores have strong canines. Tortoise and birds do not have teeth. Rodents have continuous growth of incisor teeth. Humans use false teeth called denture after they are all worn out. Cosmetic dentistry plays a vital role in face upliftment. Humans can be identified with the help of teeth records in certain calamities.  Respiratory system Breathing means inhaling oxygen and exhaling carbon-di-oxide. Humans breathe thru nose, fishes thru gills, whales and dolphins thru blow holes, insects thru spiracles and plants thru stomata. Our nose has tiny hair called cilia that stops the entry of dirt and mucus to moisten the air that enters the nose. The inhaled air enters the trachea (wind pipe).from here it enters into lungs via bronchi. Humans have 2 lungs, the left lung being smaller to accommodate the heart. The heart and the lungs are protected in the rib cage. The inhaled air finally reaches the alveoli(tiny air sacs)where exchange of gases take place. Alveoli bags burst in smokers, thereby decreasing the circulation of oxygen which eventually makes them prone to diseases. We are born with pink lungs but eventually turns black. Asthma is the narrowing of the bronchi and bronchioles, which cause difficulty in breathing. COPD is chronic obstructive pulmonary refers to chronic bronchitis and emphysema, a pair of two commonly co-existing diseases of the lungs in which the airways become narrowed. This leads to a limitation of the flow of air to and from the lungs causing shortness of breath In contrast toasthma, the limitation of airflow is poorly reversible and usually gets progressively worse over time.

Circulatory system Your heart was beating even when we were in mother’s womb.  Human have 1 heart which is protected by rib cage.  Heart is slightly on the left side and therefore the left lung is small in size, to accommodate the heart.  Heart beat can be heard with stethoscope.  Heart has 4 chambers, 2 upper chambers called auricles and 2 lower chambers called ventricles.  Heart is a muscular organ. It pumps the blood to the body.  Heart, itself is supplied by 3 arteries. If any of the arteries is blocked then the heart is unable to function to its fullest. In this condition if there is exertion then it leads to angina pain and if it is not treated in time, it can lead to myocardial infarction (heart attack).  Smoking and fatty foods increase the risk of heart attack,as it causes blockages in the artery.  Physical exercise,slow and deep breathing exercise also helps to ameliorate this condition.

Digestive system The food is cut by the teeth, softened by the saliva and relished by the tongue.untill this stage everything is voluntary, but after this stage the journey of the food becomes involuntary. From the mouth food enters the esophagus (food pipe) and into the stomach. In the stomach it is mixed with digestive juices and the food becomes unrecognizable. Now the digested food is called chyme and it enters the small intestine. In the small intestine the food and water is absorbed in the blood, making us fresh and active. <span style="font-family: Calibri; font-size: 18pt; line-height: 115%; margin-bottom: 10pt; margin-left: 0in; margin-right: 0in; margin-top: 0in;">Then it enters the large intestine where remaining water is absorbed and the rest is expelled as faeces. <span style="font-family: Calibri; font-size: 18pt; line-height: 115%; margin-bottom: 10pt; margin-left: 0in; margin-right: 0in; margin-top: 0in;">Liver secretes bile, which is stored in gall baldder.Bile enters the small intestine to digest fatty food. <span style="font-family: Calibri; font-size: 18pt; line-height: 115%; margin-bottom: 10pt; margin-left: 0in; margin-right: 0in; margin-top: 0in;">Insulin, secreted by pancreas causes cells in the liver and muscles to take up glucose from the blood., storing it as glycogen in the liver and muscle. <span style="font-family: Calibri; font-size: 18pt; line-height: 115%; margin-bottom: 10pt; margin-left: 0in; margin-right: 0in; margin-top: 0in;">Humans need to eat everyday but not a python and also not the animals that hibernate. <span style="font-family: Calibri; font-size: 18pt; line-height: 115%; margin-bottom: 10pt; margin-left: 0in; margin-right: 0in; margin-top: 0in;">The doctor gastrointestinal tract is called gastroenterologist.

EXCRETORY SYSTEM The water that we drink is absorbed in the small intestine and is passed into our blood. When the blood reaches the kidneys, it is filtered. The filtered blood goes back into the circulation whereas waste that is pulled out from the blood goes into the urinary bladder through the ureters. Humans have 2 kidneys, the size of one’s fist and are situated behind. Also we have 2 ureters, one arising from each kidney. The urinary bladder is a muscular organ that expands like a balloon and once it is full, we need to pass urine. We urinate more in winter as we sweat less and vice versa in summer. The doctor who looks into our problem of excretory system is called nephrologist (each cell of kidney is called nephron) Holding urine for a long time and drinking less water can create stones in the urinary tract and\or in kidney. We can survive with one kidney and also without kidney, but on dialysis. Dialysis means a machine does the work of filtering the waste. It is very painful, time consuming and also very expensive. So in such case we can find a donor who wishes to donate one kidney.

NERVOUS SYSTEM Brain helps us to hear, feel, see, balance, coordinate, remember and the list is endless. In short it is a juggler managing many things at a time. Brain is a soft organ with many folds and grooves, protected by skull. Spinal cord is a long and thick bundle of nerve emerging from the brain. The brain and the spinal cord is called the central nervous system. The spinal cord is protected by vertebral column, a series of 33 bones. Various nerves from the spinal cord branches out to the entire body and this is called as peripheral nervous system. Brain almost weighs 1 kg and requires water and sugar for its nourishment. Exercising the brain is a must to keep it active. Solving puzzles, Rubik cube, balancing, day dreaming are some ways of keeping our brain active. To calm our nerves we must meditate or do yoga. Doctor of the brain is called neurologist(brain cell is called neuron) Brain damage can be assessed by MRI (magnetic resonance imaging) and CT (computed topography)scan