homework

The membran consist of lipids and proteins. The membrane lipid part is formed by a bimolecular film that give structure and is a barried that prevents the passage of soluble substances.

the membrane transport

the fluid mosaic is a membrane model proposed by singer and nicolson in 1972 that an interaction of 3 classes of proteins :

integral proteins:in the middle of the membranes

glycoproteins:crosses the membrane.

peripheral proteins:aside from the membrane.

the function of the cell membrane:

is a laminar structure wich comprises the cell , defines its boundaries and helps maintain the balance between internal and outside of these. in adittion similar to the membranes that delimit the organelles of eukariotics cells.

MEMBRANE TRANSPORT.

is callest the set of mechanisms that regulate the passage of solutes such as ions and smalls molecules across cell membranes.

matias schleiden: /developed the cell theory.
theodor shwann:/developed the cell tehory.

cell theort.

it has three postulates

1)the cell is unity of structure.

2)the cell is unity of function.

3)all the living things are formed by cells

THE CELL

the parts of the cell are:

1) nuclews

2)cell membran

3)cytoplasm

the nucleolus

is a structure inside the cell ; its function is the control and direction , of the cell .

the nucleus is formed by:

nucleolus: its function is to do ribosomes.

nuclear membrane: its formeg by phospholipids and proteins . its function :give shape to nucleus.. inside of the nuclear membran . we can find nuclear juice.

the nuclear juice:its a liquid made by DNA and RNA.

ribosomes:they are in all places of the cell ; they was created in the nucleolus . the ribosomes prodece proins that are esed in the construction of the membranes.

chromosomes: they are responsible by the genetic information.

celular membrane.

is a estructure most important ; their functions are:

*protect the nucleus and cytoplasm.

*give form to the cell.

homework :

*to allow change of nutrients.

definition of cell

The cell is the morphological and functional unit of all living things. In fact, the cell is the smallest element that can be considered alive.