The Cell

Joseph

Plant Cells

• Plant cells are cells that are in plants. Plant cells are like animal cells, but they have a cell wall and chloroplasts.

Animal Cells

• Animal cells are the cells found in animals.

Nucleus

• A cell structure in plant and animal cells that acts as the control center and directs all of the cell’s activities.

Chromosomes

• A structure in a cell that contains DNA, or genetic information, which holds the plans for all pieces of the cell.

Cell Membrane

• A double layer of fat molecules that holds the contents of the cell in place and controls the movement of materials into and out of the cell.

Cytoplasm

• A watery fluid that contains everything inside the cell membrane and outside the nucleus where many of the cell’s chemical activities take place.

Vacuole

• A fluid filled space in a plant and animal cells that is used to store water and nutrients also used to store waste and move waste and excess water out of the cell.

Flagellum

• A whip like a tail that helps a cell to move.

Cillia

• Tiny hairs that work to move a cell or the fluid surrounding a cell.

Cell Wall

A structure that protects and supports a plant cell.

Chloroplasts

• A plant cell structure containing may molecules of a green pigment called chiorophyll.

Nucleolus

• The round granular structure within the nucleus of a cell, and composed of protein and RNA.

Eukaryotic Cells

• A cell that has a nucleus surrounded by a nuclear membrane.

Prokaryotic Cells

• A cell in which the nucleus is not surrounded by a membrane.

Mitochondria

• Circular or rod shaped organelles that provide the cells with energy through a process called cell respiration.

Centrioles

• A self-replicating, small, fibrous, cylindrical-shaped organelle, typically located in the cytoplasm near the nucleus in cells of most animals. It is involved in the process of nuclear division.

Cytoskeleton

• The cytoskeleton is a network of fibers throughout the cell's cytoplasm that helps the cell maintain its shape and gives support to the cell.

Endoplasmic reticulum

• A cell structure that consists of a series of folded membranes that act as canals to carry materials through the cytoplasm.

Nuclear membrane

• The double-layered membrane surrounding the nucleus of a eukaryotic cell, separating the nucleoplasm from the cytoplasm.

Nucleolus

• The round granular structure within the nucleus of a cell, and composed of protein and RNA.

Golgi apparatus

• A cell organelles that stores proteins and puts them into packages called vesicles

Lysosome

• An organelle formed by the Golgi apparatus to control and clean the cytoplasm. Lysosomes contain special proteins used to break down large molecules into smaller molecules. Lysosomes also destroy and worn out cells.

Plasma

• Fluid through which cellular components of blood, lymph, or intramuscular fluid are suspended.

Membrane

• A thin layer of tissue covering a surface or lining a cavity, space or organ.

Ribosomes

• A very small organelle that uses information from the nucleus and molecules from the cytoplasm to produce proteins.

The differences between plant and animal cells (1)

• A notable difference between animal cells and plant cells is that animal cells do not have a cell wall where as plant cells do. Both plant and animal cells have plasma membranes.

The differences between plant and animal cells (2)

•Plant cells have chloroplast for photosynthesis whereas animal cells do not have chloroplasts.

The differences between plant and animal cells (3)

•Another difference between plant cells and animal cells is that animal cells are round whereas plant cells are rectangular.

The differences between plant and animal cells (4)

•Further, all animal cells have centrioles whereas only some lower plant forms have centrioles in their cells.

The differences between plant and animal cells (5)

•Animal cells have one or more small vacuoles whereas plant cells have one large central vacuole that can take up to 90% of cell volume.

The differences between plant and animal cells (6)

• In plant cells, the function of vacuoles is to store water and maintain turgidity of the cell. Vacuoles in animal cells store water, ions and waste.

The differences between prokaryotes and eukaryotes (1)

• The difference between the structure of prokaryotes and eukaryotes is so great that it is considered to be the most important distinction among groups of organisms.

The differences between prokaryotes and eukaryotes (2)

• The most fundamental difference is that eukaryotes do have "true" nuclei containing their DNA, whereas the genetic material in prokaryotes is not membrane-bound.

The differences between prokaryotes and eukaryotes (3)

• In eukaryotes, the mitochondria and chloroplasts perform various metabolic processes and are believed to have been derived from endosymbiotic bacteria. In prokaryotes similar processes occur across the cell membrane; endosymbionts are extremely rare.

The differences between prokaryotes and eukaryotes (4)

• The cell walls of prokaryotes are generally formed of a different molecule (peptidoglycan) to those of eukaryotes (many eukaryotes do not have a cell wall at all).

The differences between prokaryotes and eukaryotes (5)

•Prokaryotes are usually much smaller than eukaryotic cells.

The differences between prokaryotes and eukaryotes (6)

• Prokaryotes also differ from eukaryotes in that they contain only a single loop of stable chromosomal DNA stored in an area named the nucleoid, while eukaryote DNA is found on tightly bound and organised chromosomes. Although some eukaryotes have satellite DNA structures called plasmids, these are generally regarded as a prokaryote feature and many important genes in prokaryotes are stored on plasmids.

• Prokaryotes have a larger surface area to volume ratio giving them a higher metabolic rate, a higher growth rate and consequently a shorter generation time compared to Eukaryotes.

The differences between prokaryotes and eukaryotes

(7)

• Prokaryotes also differ from eukaryotes in the structure, packing, density, and arrangement of their genes on the chromosome. Prokaryotes have incredibly compact genomes compared to eukaryotes, mostly because prokaryote genes lack introns and large non-coding regions between each gene.

The differences between prokaryotes and eukaryotes

(8)

The differences between prokaryotes and eukaryotes (9)

•Whereas nearly 95% of the human genome does not code for proteins or RNA or includes a gene promoter, nearly all of the prokaryote genome codes or controls something.

The differences between prokaryotes and eukaryotes (10)

•Prokaryote genes are also expressed in groups, known as operons, instead of individually, as in eukaryotes.

differences between prokaryotes and eukaryotes (11)

– In a prokaryote cell, all genes in an operon(three in the case of the famous lac operon) are transcribed on the same piece of RNA and then made into separate proteins, whereas if these genes were native to eukaryotes, they each would have their own promoter and be transcribed on their own strand of mRNA. This lesser degree of control over gene expression contributes to the simplicity of the prokaryotes as compared to the eukaryotes.