explain the structure and function of human body
Answers
The human body is a complex system with structures ranging from cells to organ systems and functions ranging from waste removal to protection and defense. The structures and functions are dedicated to maintaining a state of health in the body.
Most people are familiar with the functions of the major organs in the human body, but cells are where the magic happens. Starting from a single cell, the human organism ends up with over 200 different kinds of cells. A cell is a membrane-enclosed compartment containing molecular machinery dedicated to carrying out metabolic reactions and maintaining the genetic material. Each kind of cell is specialized to carry out a task within the body. Some cells carry oxygen through our bloodstream (red blood cells); some contract and power our movements (muscle cells); and some process and transmit information about our environment and our bodies (brain cells). That is, of course, just to name a few.
These hardworking little cells end up organizing and grouping together to form the four tissue types in the body. A tissue is a specialized group of cells and their products that function together. The four tissue types in the human body are as follows: epithelial, muscle, nervous, and connective tissue. Epithelial tissue is great for building structures with walls and passageways and compartments. Muscle tissue has cells organized and coordinating together to contract and move. Nervous tissue consists of neurons linked together in vast networks for transmitting and receiving information. Finally, connective tissue provides much of the physical structures and supports within the body and includes materials like cartilage, fat, bone, and blood.
If you take some tissues and combine them into a larger structure that has a dedicated function, you have created an organ. You are probably familiar with organs - things like the heart, lungs, liver, and kidneys. We think of the heart as contracting and providing the force necessary to pump our blood. It is dedicated to that task. We don't expect that sometimes the kidneys will do the pumping, and sometimes the brain will do the pumping, and so on. We expect that the heart will carry out that function our entire lives.