The Golgi apparatus in a plant cell.
Sunday, November 30, 2008
Golgi Apparatus
The Golgi apparatus, or Golgi bodies, are used as vesicles in which proteins from the rough ER are packaged and moved to either lysosomes, the plasma membrane, or for secretion. The Golgi bodies function in plants slightly different because they serve as the site at which the complex polysaccharides of the cell wall are synthesized.

Ribosomes
Ribosomes are what makes the rough ER rough. They are composed of RNA and protein and are where protein synthesis takes place. Ribosomes are also found in the mitochondria and choloroplasts (only found in plants) in eukaryotic cells.

Ribosomes in a liver cell.
Rough Endoplasmic Reticulum
The rough endoplasmic reticulum are 'rough' because ribosomes, which are needed to carry out protein synthesis, are attached to the surface. Each protein made in the rough ER has a specific function.

This picture shows the rough ER studded with ribosomes.
Smooth Endoplasmic Reticulum
The smooth endplasmic reticulum, also know as SER, is involved in various metabloic processes. It is 'smooth' because it does not contain ribosome like the rough ER. It is connected to the nuclear envelope and is known for its storage of calcium irons in muscle cells.

Wonderful picture of the Smooth ER.
Saturday, November 29, 2008
Vacuole
Vacuoles are used in both plants and animals for transport and to store nutrients, metabolites, and waste products. There is a membrane surrounding the plant cell vacuole called the tonoplast which is a very active and dynamic membrane. The plant vacuole is naturally bigger than the animal vacuole for the fact that plants need the extra space since they make food through photosynthesis.

Cytoplasm
Located within the cell, cytoplasm is a jelly-like substance that includes all of the organelles of the cell as well as what is needed for cell growth and reproduction. The cytoplasm contains dissolved nutrients and salts, helps dissolve waste products, and is an excellent conductor of electricity.
This picture shows various organelles within the cytoplasm.
Nucleus
The nucleus is, of course, the 'brain' of the cell. It controls all the functions of the cell and in it it holds the genetic information that's called chromatin. Also inside the nucleus is the nucleolus, an organelle that synthesizes protein-producing macromolecular assemblies called ribosomes.

The nucleus itself is enclosed in a double-layered membrane called the nuclear envelope. This envelope is filled with holes called nuclear pores that allow specific molecules to pass back and forth between the nucleus and the cytoplasm.
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