Biology: Plant Cell Features & Functions

A system of flattened membrane

A cell is a membrane bound unit containing hereditary machinery and other components including enzymes by virtue of which it is able to metabolise substances to grow and reproduce

Plasma membrane encloses protoplasm

It surrounds the cell isolating from outside

Nuclear region

Directs the activities of cell

Cytoplasm occupies the volume between the nuclear region & cell membrane

Food materials are stored in the cytoplasm & chemical reactions take place building up materials and supplying energy for cell activity.

The nucleus contains nucleolus together with small chromatin granules that appear when cell undergoes pision

Chromosomes carry hereditary material determining the organisms characteristics and transmitting these to subsequent generations

The centriole is influential in cipa and flagella formation

These are slender motile haura that project from surfaces of certain cells

Plant cells has additional features to those of animal cell.

The centre is the vacuole containing cell sap (solution of sugars and salts)

Cell is bounded by cellulose which is a thick wall made of polysaccharide carbohydrate

Sap vacuole and cell wall maintain the shape & form of cell.

Plasma membrane are the outer surface of the cytoplasm (in contact with cellulose wall).

The tonoplasts are the inner surface bordering the vacuole.

The middle lamellar is the point of demarcation between one cell and the next. It represents the fuses pectate walls of two adjoining cells.

Plasmodesma strands (plasmodesmata) facilitate movement of materials between cells.

They also facilitates the deposition of cellulose during the thickening of secondary cell wall.

Plastisa are of 2 types leucoplasts and chloroplasts.

Leucoplasts are colourless and contain starch.

Chloroplasts contain chlorophyll crucial for photosynthesis.

The endoplasmic reticulum is an extensive system in photosynthesis that pides the interior cells into compartments and channels.

Ribosomes are sites where proteins are synthesised in the cell.

The bulk of endoplasmic reticulum is encrusted with ribosomes and it is the rough endoplasmic reticulum.

It is devoted to the synthesis and transport of proteins across the membrane.

The endoplasmic reticulum is devoted to organising the synthesis of lipids and other biosynthetic activities.