1- Human body (total organism) is complicated &
highly organized & composed of number of systems:-
-Musculoskeletal system.
-Respiratory system.
-Cardiovascular system.
-Hemic and lymphatic systems including immune system.
-Gastrointestinal system.
-Urogentital system.
-Endocrine system.
-Nervous system.
-Integumentary system:- skin, hair and nails.
2- One system is composed of group of organs which
together perform the over all function of the system.(1)
3- An organ :- is composed of several different tissues
which together perform the particular function of the organ.
4- A Tissue :- is a group of cells working together &
these cells are separated by inter-cellular substance.
e.g Muscular tissue & neural tissue.(1)
5- Cell :- is the smallest living unit of the body construction (2)&
it is the structural & functional unit in the body.
cell is composed of complex structure called protoplasm.(2)
In eukaryotes the protoplasm surrounding the cell nucleus
is known as the cytoplasm and
that inside the nucleus as the nucleoplasm.(3)
6- Protoplasm is composed of a mixture of different molecules :-
- water 70%
- proteins 15%
- nucleic acids 1%
- polysaccharides 3%
- lipids 1%
- Minerals & others 4%
7- Molecules are formed of elements :-
- carbon (C)
- hydrogen (H)
- oxygen (o)
- Nitrogen (N)
- phosphorus (p)
- sulfur (s)
Elements are substances which cannot be broken down further
by ordinary chemical means
*References:-
(1) Introduction to anatomy ,Anatomy & embryology department,
Mansoura uni 2006.
(2) Principles of histology vol 1 , Ch 2 cytoplasm,
histology staff members , Mansoura uni 2006.
(3) wikipedia here
(4) Medical biochemistry, Vol 1,Physical chemistry,
Medical biochemistry staff members,2006.
