Plant And Animal Cells

Plant and Animal Cells

I. Introduction

All organisms in life are composed of at least one or more

cells. Cells are the basic units of life. There are three main

features of a cell. First, all organisms consist of one or more

cells. Second, cells are the smallest units of life and third,

cells arise only from preexisting cells. These three facts are

referred to as the cell theory.

All cells can be categorized into two basic cell types.

They are prokaryotic and eukaryotic. To distinguish where cells

are placed in the two categories, what is inside the cell must

first be looked at. Every cell, either prokaryotic or eukaryotic

all contain basic cell parts. They are: a plasma membrane,

cytoplasm, DNA (the genetic material), and ribosomes.

Prokaryotic cells have a simple structure and they are usually

smaller than eukaryotic cells. Also, most prokaryotic cells

contain a cell wall. In addition to having the basic cell parts,

eukaryotic cells also contain a membrane-bounded nucleus and cell

organelles. The membrane surrounding the nucleus in eukaryotic

cells, separate the nucleus from the cytoplasm.

Most of the cells we used in the experiments held, were

multicellular or consisting of more than one cell. A variety of

cells were used in completing the experiments. We used union

cells, cheek cells, potato cells, and Elodeo cells. We also used

Planaria which is a unicellular organism. Many stains and dyes

were used in the experiments. They were water, methylene blue,

salts, and iodine.

In our studies of cells, we conducted three experiments to

test the different features of cells. The first two experiments

were on how membranes were selectively permeable, diffusion, and

osmosis. To test this, we set up two experiments. The first

experiment we set up had three cups. In each cup a potato slice

and a different liquid was put in. In the first cup was filled

with distilled water. The second cup was filled with salt water

and the third was left empty. We left these cups sit for twenty-

four hours and then we observed them.

The second experiment we set up involved dialysis tubing

which was acting like a membrane. In the dialysis tubing we put

a liquid that was made of starches and sugars. We then put the

dialysis tubing into a beaker of water wh...

... middle of paper ...

...c solution and sucked up some of the water in the

cells.

When we observed the cheek cells we found they were very

different from the plant cells. The nucleus was in the middle of

the cheek cells and there were a few cell organelles. The

Planaria cell was all red and had lines running down it. In this

cell though, the nucleus was not present.

The plant cells and animal cells were very different. In

the plant cells there was motion of cell parts but in the animal

cells there was no motion. Also, the nucleus and chloroplast of

the plant cell were towards the outside of the cell because the

chloroplast can receive sunlight better on the outside of the

cell than on the inside. In the animal cells though, the nucleus

and cell organelles, were towards the middle of the cell.

III. Conclusions

All organisms in life are made of at least one or more

cells. Cells are the basic units to life. Without cells life

cannot exist. In our experiments we went to look how cells

function and what are their features. In finding this

information, I know have a better understanding of how cells

function and their specific features.