Our Human Body represents the entire structure of the human organism. It consists of trillions of cells that are organised biologically to form the entire human body.
Human body contains different organ systems consisting of various organs. These organ systems are constructed wonderfully to perform various functions. All the organ systems are structurally and functionally coordinated with one another.
Health is an important factor for the well being of human body. Health is a state in which all the organs function normally and properly that helps in prolonging the life of an individual. Health also improves the quality of life.
The type and composition of the body are influenced by diet and exercise.
We need to take proper care of the human body so that all the organs function effectively. Hygiene is the branch of science which tells us how to keep the body and organs in proper working condition. It helps us to improve our health and to protect ourselves from various diseases.
Safety tells us about the measures to be taken to avoid accidents. First aid is the help given to protect an injured person before taking to a doctor.
Human body is a masterpiece of creation and is comparable to a machine. Like machine consisting of a number of parts with a specific function, human body also has many organs with specific functions. Fuel is required for the machines to function properly likewise food is needed for the human body for obtaining the energy.
A machine functions properly when all its parts work collectively and it is controlled by man. The human body also works properly when there is a coordination between all parts and it can control itself. The human body has the ability to reproduce whereas the machines cannot.
The basic structure of the human body is a cell. There are a number of specialised cells for specific functions. The specialised cells are organised to form tissues and the tissues are organised to form organs with a specific function. Organs are grouped together to form organ systems which altogether constitute the human body with proper coordination.
The integumentary system is the largest organ system of the human body and its primary function is to protect the body by acting as a physical barrier and the first line of defence against various physical and environmental factors
Skin is the largest organ of the body and forms the outer covering of the body. Healthy skin is an index of a healthy body.
Integumentary system also consists of appendages like sweat and sebaceous glands, nails and hair.
Musculoskeletal system consists of a human skeleton made by bones. The bones are attached to other bones with the help of joints. The muscles of the skeletal system are attached to bones by the help of tendons. Human body contains 206 bones.
Skeletal system gives support to the body and protects the organs. Bone and cartilage are the components of the skeletal system. Bone is hard and cartilage is soft tissue.
Muscular system helps in the movement of the organs and to the body as a whole.
Nervous system coordinates the activities of the various organs of the body. Brain is the important organ of the nervous system and is the seat of intelligence and thinking.
(Cardia = heart, Vasculature = blood vessels). We generally call it as the “Circulatory system” and it consists of heart and blood vessels. The blood vessels consist of arteries, veins and capillaries.
Heart comprises of three layers namely endocardium, myocardium and epicardium. These layers vary in thickness and also in function. The epicardium is the outermost layer of the heart and endocardium is the innermost layer. The three layers are together known as pericardium of the heart.
The primary function of the heart is to pump the blood (circulate the blood) throughout the body. The heart also transports oxygen and vital minerals to the tissues and organs of the body along with the blood.
Left side of the heart (Left atrium and ventricle) pumps blood to all parts of the body which is the oxygenated blood whereas the right side of the heart (Right atrium and ventricle) collects deoxygenated blood from all organs and pumps to the lungs for oxygenation of the blood.
The blood vessels that carry the blood to the organs are called arteries and the blood vessels that collect the impure blood from the organs are called as veins. Blood is red in colour due to the presence of the pigment haemoglobin. It transports various substances to the different parts of the body.
The respiratory system consists of lungs. Inhalation (taking in) of oxygen and expiration (leaving out) of carbon dioxide are carried out by the lungs.
The digestive system consists of mouth, stomach and intestine. It digests the food and distributes the digested food to the various parts of the body. The digestive system processes the food and transforms nutrients into energy.
Certain organs (glands) like liver and pancreas are present that secrete the necessary substances required for digestion. Other glands like pituitary and thyroid secrete chemical substances known as hormones. These glands do not have ducts so they are known as endocrine glands or ductless glands.
The excretory system removes the waste substances formed in the body. Kidneys are the main excretory organs. The urinary system helps in filtering out the water and useful substances like glucose, amino acids into the vascular system and excreting the waste substances.
The reproductive system consists of reproductive organs like testis in male and ovaries in female. Their function is to give rise to a new generation of young ones. Testis in males produces sperms and ovaries of female produce ovum, which get fused to form a zygote which gives rise to a new individual.
The lymphatic system is similar to a circulatory system in terms of the structure and functions. The main function of the lymphatic system is to transport and metabolise lymph which is present between the cells.