cells? website?

Question

what iss a good website about cells and their parts? What are ribosomes and the endoplasmic riticulum?

Answer 1

A good website to look up information about cells is: http://www.howstuffworks.com/cell.htm

Ribosomes and endoplasmic reticulam: Endoplasmic reticulum is a network of tubules, vesicles and sacs that are interconnected. They may serve specialized functions in the cell including protein synthesis, sequestration of calcium, production of steroids, storage and production of glycogen, and insertion of membrane proteins. The first part of this presentation will focus on rough endoplasmic reticulum which gets its name from the presence of ribosomes on its surface. The text reading for this discussion is Alberts et al, Molecular Biology of the Cell, third edition, Garland Publishing, 1994, pp 577-588 (Chapter 12) and pp 599-616. All of the figures in these web pages are linked to a page listing the citation from which the figure was taken. Click on the figure to learn the citation. If there is no link, the figure came from our own collection
Rough endoplasmic reticulum bears the ribosomes during protein synthesis. The newly synthesized proteins are sequestered in sacs, called cisternae . The system then sends the proteins via small vesicles to the Golgi Complex , or, in the case of membrane proteins, it inserts them into the membrane. As shown in this diagram, rough endoplasmic reticulum may either be vesicular or tubular. Or it may consist of stacks of flattened cisternae (like sheets) that may have bridging areas connecting the individual sheets. The Ribosomes sit on the outer surfaces of the sacs (or cisternae). They resemble small beads sitting in rosettes or in a linear pattern.

Rough endoplasmic reticulum forms a branched reticulum that expands as the cell becomes more active in protein synthesis. Sometimes the reticulum branches out. Other times, the cisternae dilate and form large sacs that fill the cell. This photograph, taken from your text, shows the reticulum delineated by immunolabeling for newly synthesized protein (labeled fluorescent blue in this photo).

Answer 2

Ribosomes are responsible for assembling the proteins of the cell. Ribosomal subunits are synthesized by the nucleolus (ribosomes are composed of a small and large subunit) but they attach to the endoplasmic reticulum or ER. There are two kinds of ER. Rough ER is attached to the ribosomes; smooth ER is not. The ER (both rough and smooth) function to transport materials within the cell. There are tons of websites you can go to..i typed in cell biology and got this one..good luck
http://biology.clc.uc.edu/courses/bio104/cells.htm

Answer 3

Ribosomes are small organelles in the cell were proteins are put together and endoplasmic reticulum (ER) is network of tubules and vesicles that pack and move proteins inside the cell.
Think of Ribosomes and ER as a sausage factory: Ribosomes are were all the ingredients in a sausage are put together and ER is were the sausages are packaged and send out for sale.