biology differences in animal and plant cells

Within the nucleus is the Nucleolus, It is a small structure within the nucleus that forms ribosomes which then pass into the cytoplasm to produce protein (Moth.E 2003)

The cell membranes is a fine membrane made of protein and lipids, it has two functions to keep the cytoplasm and the nucleus in.

Plant and animal cells contain mitochondria, they are distinct organelles with two membranes, usually they are rod shaped, however they can be round, the outer membrane limit's the organelle, the inner membrane in thrown into folds or shelves that project inward, the organelles contain enzymes which convert food material into ATP (Adenosine Triphosphate) (Toole.G and Toole S 1999) which can be used directly by the cell for energy which is needed in order to function and reproduce.

Sarah Huckerby Biology Group 1

E.R (endoplasmic reticulum) they are a network of membranes that form a system of sacs and canals within the cytoplasm.

They serve many specialized functions in the cell including protein synthesis, production of steroids, storage and production of glycogen and insertion of protein membranes, the two types of E.R are rough and smooth, it forms a branched reticulum that expands as the cell becomes more active in protein synthesis, Smooth endoplasmic reticulum is found is a variety of cell types and it serves different functions in each.

It contains tubes and vesicles that branch forming a network in some cells they are dilated areas like the sacs in the rough E.R. The smooth E.R allows increased surface area for the action or storage of key enzymes.

Plant and animal cells also contain Ribosomes these produce proteins needed for growth and repair of the cell. Each ribosome is built from two sub-units each having its own mix of ribosomal RNA (ribonucleic acid)

and proteins. Ribosomes are built with RNA from the nucleolus and are made in the nucleus itself, they function in protein synthesis, as they move along messenger RNA, amino acids are joined in order originally dictated by DNA.

Plant and animal cells also contain Golgi apparatus, they secrete carbohydrates and combine them within the protein in order to send them to other parts of the cell or out of the cell, and they are stacks of flattened sacs of unit membrane (cisternae) the stack of larger vesicles is surrounded by numerous smaller vesicles containing macromolecules.

Plant and animal cells also have many differences; plant cells are larger and have a regular shape, whereas animal cells are usually smaller and irregular. In animal cells there is no cell wall present as it is not needed because the animal cells are smaller it is needed in a plant as the plant cell is larger.

In plant cells the cellulose wall is present outside, which confers some rigidity and shape, this is capable of stretching when the cell is young but later becomes tougher and can be impregnated with various materials.

Plasmodesmata and pores are present in a plant cell, they are needed as the dead cell walls around plant cells isolate the cell, so pores and plasmodesmata are needed for communication and passage of materials between cells, these do not occur in animal cells because substances can pass easily between cells through the thin cell membrane.

Sarah Huckerby Biology Di Paul Group 1

A larger singular vacuole is present in plant cells, the vacuole in plant cells helps to support the cell from the inside, it also stores some wastes. In animal cells these are smaller and more numerous extra internal support is not needed in the smaller animal cells also wastes are removed from animal's cells.

In plants tonoplasts are present, they are a semi-permeable membrane surrounding a vacuole, and it stores large amounts of water.

Plant cells sometimes contain chloroplasts these are specialised organelles found in all higher plant cells and contain chlorophyll (the green colour in green plants) chloroplasts have a double outer membrane. Green plant cells can produce food by photosynthesis; however chlorophyll never occurs in animal cells as animal cells obtain food from other sources because they cannot make their own food,

Lysosomes are membrane bound organelles, thought to form by Golgi bodies which contain strong enzymes. When a lysosome is formed it is able to fuse with a vesicle in which there is a substance to be digested, in plant cells these do not occur as the vacuole carries out a similar function in plant cells. They are present in animal cells to keep the cell healthy as they play a part in defence of our bodies defence system.

Centrioles are only found in animal cells, in the animal cell they are needed to make cilia (tiny hair like projections for example in the air passages) they keep certain passages like the wind pipe passages clear.

In plant cells centrioles are not needed as cilia are not not present in the plant cell.

Between the walls of a plant cell, middle lamella is present and joins cell walls of adjacent cells (Toole.G & Toole.S 1999)

They are joined by intercellular cement. In animal cells they are not present as the middle Lamella holds plants cells together, and acts as demarcation between one cell and the next.

Sarah Huckerby biology Di paul group 1

Plant and animal cells have many similarities. However there are differences.

The plant cell is much larger and has a regular shape animal cells have their own ways of storing and producing secretions.

Some plant cells contain chlorophyll and give us the green colour in most plants, but animal cells never contain chlorophyll.

That even with a lot of differences and similarities, both types of cell are there to define life and reproduce further.