Question

) Draw a plant cell & label the parts which
a) Determine, the function and development of the cell​

Answer 1

Answer:

Explanation:

(a) Nucleus: It determines the function and development of the cell

(b) Golgi apparatus: It packages materials coming from the endoplasmic reticulum

(c) Cell wall: It provides resistance to microbes to withstand hypotonic external media without bursting

(d) Cytoplasm: It is a is site for many biochemical reactions necessary to sustain life.

(e) Nucleoplasm: It is a fluid contained inside the nucleus

Answer 2

Question:

Draw a plant cell & label the parts which

a) Determine, the function and development of the cell​

Explanation:

If a thin slice is taken from any part of a plant and observed under a microscope, it is found to be composed of many chambers or compartments resembling the chambers of a honeycomb. Each of these chambers is called a cell. A plant cell has usually an outer firm non-living boundary called the cell wall and a cavity which contains granular jelly-like protoplasm.

A cell is defined as the unit of structure and function. It is a unit of structure more or less in the same sense as a piece of brick is a unit in a building. Plant-body is built up structurally of cells-. It is called a unit of function, because a cell contains a unit mass of proto­plasm which is solely responsible for all the vital activities.

In 1665 an Englishman Robert Hooke observed a thin slice of bottle cork under a microscope improved by himself. He noted many chambers and suggested the term ‘cell’, on the basis of their resemblance with the so-called cells or chambers of a bee-hive.

As bottle cork is a dead thing Hooke certainly noticed only the cell wall and not protoplasm. Italian Professor Marcello Malpighi (1628-94) and English physician Nehemiah Grew (1641-72) also carried on studies on cellular structures.

A theory, known as ‘cell theory’, was postulated by Matthias Jacob Schleiden (1804-81). a German botanist, and Theodor Schwann (1810-82), a German zoologist (Fig. 115), in 1838-39, who claimed that all living things, plants and animals, are cellular in nature, i.e. they are essentially made up of cells.

The announce­ment of cell theory was an incident of paramount import­ance in the history of our knowledge about cell. Early workers concentrated their attention practically on the distinct cell wall, possibly because the transparent proto­plasm escaped their notice.

 

Thomas Henry Huxley in 1868 described it as ‘the physical basis of life’. Hanstein in 1880 proposed the term protoplast for a cell.

Though even today we use the term cell as proposed by Hooke, present-day conception of a cell is that it is essentially a mass of protoplasm (protoplast) with or without the wall. In contradistinction to animal cells, the plant cells are usually walled.

Even in plant kingdom ‘naked’ cells, i.e. cells without walls are not altogether absent. Reproductive cells are usually naked. A cell is called dead, when it has lost its protoplasm like the cells of bottle- cork noted by Hooke.

Cells are so numerous and diverse that it is rather difficult to give a precise account of their shape and size. All shapes between round or circular on one hand and ‘elongate needle-like on the other, are possible