WHAT IS CELL WALL AND ITS FUNCTION??

CELL WALL

DEFINITION;

★CELL WALL IS A NON-LIVING AND STRONG COMPONENT OF CELL.

PRESENCE;

★WE KNOW THAT NOT ALL LIVING ORGANISMS HAVE CELL WALL

AROUND THEIR CELLS, LIKE ANIMALS AND ANIMAL LIKE PROTIST.

LOCATION;

★IT IS LOCATED INSIDE THE PLASMA MEMBRANE.

FUNCTION;

★IT PROVIDES SHAPE, STRENGTH, PROTECTION AND SUPPORT TO THE

LIVING MATTER (PROTOPLASM) OF CELL.

LAYERS AND CHEMICAL COMPOSITION;

★PLANT CELLS HAVE VARIETY OF CHEMICALS IN THEIR CELL WALLS.

PRIMARY WALL;

★THE OUTER LAYER OF PLANT CELL WALL IS KNOWN AS PRIMARY WALL.

CHEMICAL;

★AND CELLULOSE IS THE MOST COMMON CHEMICAL IN IT.

SECONDARY WALL;

★SOME PLANT CELLS FOR EXAMPLE; XYLEM CELLS, ALSO HAVE

SECONDARY WALLS ON THE INNER SIDE OF PRIMARY WALL.

CHEMICAL;

IT IS MUCH THICKER AND CONTAIN LIGNIN CHEMICAL.

MIDDLE LAMELLA;

★THE MIDDLE LAMELLA IS FIRST TO BE FORMED IN BETWEEN

THE PRIMARY WALLS OF NEIGHBOURING CELLS.

PLASMODESMATA;

★THERE ARE PORES IN THE CELL WALLS OF ADJACENT CELLS,

THROUGH WHICH THEIR CYTOPLASM IS CONNECTED. THESE

PORES ARE CALLED PLASMODESMATA.

FUNGI AND MANY PROTISTS;

★FUNGI AND MANY PROTISTS HAVE CELL WALL ALTHOUGH THEY

DO NOT CONTAIN CELLULOSE. THEIR CELL WALLS ARE MADE OF

A VARIETY OF CHEMICALS.

FOR EXAMPLE;

➤CHITIN

★CHITIN IS PRESENT IN THE CELL WALL OF FUNGI.

➤PEPTIDOGLYCAN

★PROKARYOTES HAVE A CELL WALL COMPOSED OF PEPTIDOGLYCAN

THAT IS A COMPLEX OF AMINO ACIDS AND SUGARS.