Table of Contents
- 1 What can you compare a endoplasmic reticulum to?
- 2 What is the ER in a cell like?
- 3 What’s an analogy for a cell?
- 4 What can the mitochondria be compared to?
- 5 How does the ER and cell membrane work together?
- 6 How do ER Golgi and vesicles work together?
- 7 How big is the ER in a cell?
- 8 What makes the ER different from other reticulums?
What can you compare a endoplasmic reticulum to?
The endoplasmic reticulum is like the highway system because the cell uses the endoplasmic reticulum to move material throughout the cell like people use highways to move throughout the country.
What is the ER in a cell like?
endoplasmic reticulum (ER), in biology, a continuous membrane system that forms a series of flattened sacs within the cytoplasm of eukaryotic cells and serves multiple functions, being important particularly in the synthesis, folding, modification, and transport of proteins .
How are the ER and Golgi apparatus related?
The endoplasmic reticulum takes the proteins that are made by the ribosomes and folds them into sacs that are called cisternae. It then transports these folded proteins to the Golgi apparatus. Molecules leave the ER in what are called transition vesicles (sacs) and enter the Golgi apparatus.
What role does the ER play in a cell?
The ER is the largest organelle in the cell and is a major site of protein synthesis and transport, protein folding, lipid and steroid synthesis, carbohydrate metabolism and calcium storage [1–7].
What’s an analogy for a cell?
| Cell Organelles | City Analogies |
|---|---|
| Cell Wall | City Wall |
| Cytoplasm | Lawns |
| Endoplasmic Reticulum | Highway or road system |
| Ribosomes | Lumber or brick yard |
What can the mitochondria be compared to?
Usually, mitochondria are compared to power plants. They are the power plants of the cell because they generate most of the cell’s ATP energy, adenosine triphophsate. Mitochondria are also used for signaling, cellular differentiation, cell growth and cell death.
Where is the ER located in a cell?
The endoplasmic reticulum (ER) is a network of membrane-enclosed tubules and sacs (cisternae) that extends from the nuclear membrane throughout the cytoplasm (Figure 9.1). The entire endoplasmic reticulum is enclosed by a continuous membrane and is the largest organelle of most eukaryotic cells.
How do the ER and cell membrane work together?
Membranes and their constituent proteins are assembled in the ER. This organelle contains the enzymes involved in lipid synthesis, and as lipids are manufactured in the ER, they are inserted into the organelle’s own membranes. This happens in part because the lipids are too hydrophobic to dissolve into the cytoplasm.
How does the ER and cell membrane work together?
After proteins are synthesized, a portion of the rough endoplasmic reticulum pinches off and separates to form a protein-filled vesicle. From there the vesicles carry the protein to another organelle where it will be used within the cell or to the plasma membrane for secretion.
How do ER Golgi and vesicles work together?
The Golgi complex works closely with the rough ER. When a protein is made in the ER, something called a transition vesicle is made. This vesicle or sac floats through the cytoplasm to the Golgi apparatus and is absorbed. From there, the vesicle moves to the cell membrane and the molecules are released out of the cell.
Why is the smooth ER important?
The smooth ER is involved in the synthesis of lipids, including cholesterol and phospholipids, which are used in the production of new cellular membrane. In certain cell types, smooth ER plays an important role in the synthesis of steroid hormones from cholesterol.
How does ER help in synthesis of membranes in a cell?
How big is the ER in a cell?
The table shows that the membrane area allocation is dominated by the ER (as much as 60%) followed by the Golgi and mitochondria. The cell plasma membrane in these mammalian cells tends to be a small fraction of less than 10%. In terms of volume, the ER can comprise >10% of the cellular volume as shown in Table 2.
What makes the ER different from other reticulums?
The ER can be classified in two functionally distinct forms: smooth endoplasmic reticulum (SER) and rough endoplasmic reticulum (RER). The morphological distinction between the two is the presence of protein-synthesizing particles, called ribosomes, attached to the outer surface of the RER.
Why is the ER important to the cell?
The ER is also noted for producing most of the lipids that make up the cell’s membranes. Finally, the ER is the main calcium deposit site in the cell, thus functioning as the crossroads for various intracellular signaling pathways. Serving as the equivalent of a corporate mailroom, the ER activity and thus size depends on the state of the cell.
Why are ribosomes important to the function of the ER?
While attached to the ER, ribosomes make proteins that the cell needs and also ones to be exported from the cell for work elsewhere in the body.