a cell

CELL

     A Cell is the smallest structural unit of an organism that is capable of independent functioning,consisting of cytoplasm, usually having one nucleus, and various other organelles, all surrounded by a semipermeable cell membrane.

Cell Theory

     While observing dead cork samples with a crude lens, Robert Hooke identified and named “cells.” He thought that the small, simple units looked like the bare prison cells of his time, and the name cell stuck. His work launched a new frontier in scientific exploration that led to modern cell theory: 

• All living things are made of cells. 
• Cells are the basic units of structure and function in all living things. 
• All cells come from the reproduction of existing cells. 

Plant Cell

Plants cell constitute of membrane bound nucleus and many cellular structures. These organelles carry out functions that are necessary for the proper functioning and survival of the cell. The cell organelles of the plant are enclosed by a cell wall and cell membrane. The constituents of the cell are suspended in the cytoplasm or cytosol. 

Structure:

There are nine parts of a plant.

The parts of the plant cell are as follows: 

Cell wall is the outermost rigid covering of the plant cell. It is a salient feature of plant cell. 

Cell membrane or the plasma membrane is the outer lining of the cell inside the cell wall. 

Cytosol or cytoplasm is the gel-like matrix inside the cell membrane which constitutes all other cell organelles.

Nucleus is the control center of the cell. It is a membrane bound structure which contains the hereditary material of the cell - the DNA 

Chloroplast is a plastid with green pigment chlorophyll. It traps light energy and converts it to chemical energy by the process of photosynthesis. 

Mitochondria carries out cellular respiration and provides energy to the cells.

Vacuoles are the temporary storage center of the cell.

Golgi body is the unit where proteins are sorted and packed.

Ribosomes are structures that assemble proteins.

Endoplasmic reticulum are membrane covered organelles that transport materials