Human Body

The human body functions as a whole, but it is composed of many separate functional units that must work together.

The smallest and mot basic unit of life is called the cell.
Cells have three parts:
the cytoplasm
the cell membrane
the nucleus
All the cell have three functions:
reproduction
movement of fluid thought the cell membrane
metabolism

Groups of similar cells form tissues:
epithelium
connective tissues
muscle tissues
nerv tissues
Epithelium main function protection.
Connective tissue supports and shapes the body.
Muscle tissue enable movement.
Nerv tissue transmits eletrical impulses in the body.

In the body there are a lot of organs that form systems.
In our body are nine systens:

I.) The musculoskeletal systém
a.) the sceletal systém
a frameworks for the body
protects vital organs
consists of bones and joints
b.) the muscle system
its functions are connected with skeletal systém
the purpose of it – a movement (coused by contraction and extension muscles)

II.) The circulatory systém
consists of the heart and a network of blood vessels:
arteries
capillaries
veins

III.) The digestive systém
consists of: the mouth, the oesophagus, the stomach, small and large intestine, the anus

IV.) The respiratory systém
consists of: the nose, the nosopharynx, the trachea, the bronchi and the lungs

V.) The urinary systém
consists of: the kydneys, the ureters, the bladder and the urethra

VI.) The nervous systém
consists of: the brain, the spinal cord (peripheral nerves, automic nerves)

VII.) The endocrine systém
consists of: seven glands that produce hormones

VIII.) The reproductive systém
there are two systems (male´s and female´s)

IX.) The integumentary systém
protects the body agains injury = the skin

Organs of the body are positioned withen spaces called cavities:
the cranial
the spinal
the thoracic
the abdominal
the pelvic