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Cell or Plasma Membranes
Every cell has a cell membrane (plasma membrane) that separates the interior of the cell from the outside environment. One of the most important functions of this biological membrane is to protect the cell from outside threats by controlling the movement of substances in and out of the cell.
1,116 Questions
Three components of the plasma membrane other than phospholipids?
- Cholesterol - helps maintain membrane fluidity and stability.
- Proteins - fulfill various functions such as transport, signaling, and structural support.
- Carbohydrates - act as recognition sites and play a role in cell-cell interactions.
How do you cure Smooth Endoplasmic Reticulum in ovary?
The smooth endoplasmatic reticulum is a part of cells, not a disease. The cells of your ovary all have one, and they need it to function.
Why is The plasma membrane is much more permeable to K than to Na?
Even when both those atoms are encapsulated with water, potassium is smaller than sodium.
What is hydrophobic in cell membrane?
Only partially permeable (semipermeable), to allow certain, relatively small molecules such as simple sugars, oxygen and lipids in and out of the cell, but at the same time keeping larger macromolecules out.
Which molecules difuse through the lipid portion of the plasma membrane?
Only nonpolar (hydrophobic) molecules can pass through the bi-lipid membrane. For example, hormones are nonpolar, and they can pass through the membrane.
Water crosses plasma membranes through specialized channels?
Water crosses plasma membranes through specialized channels called diffusion and concentrated gradient.
In a plasma membrane how do tails of the phospholipid molecules line up?
they are sandwiched between two layers of heads
No. It is produced by the liver and stored in the gall bladder. It is released when you eat a fatty meal.
When does diffusion occur across a cell membrane?
Diffusion across a cell membrane occurs when concentrations of a substance are higher either inside or outside the cell.
What is plasma responsible for?
Plasma is responsible for burning other cells in the system of each the plant and animal ones.
When a cell is very thin what possible disadvantages might there be to such a cell shape?
Reduced volume of cytoplasm to carry out normal cellular functions.
What is a relatively thin and flexible wall secreted first by a cell?
It is called the cell plate. After it turns into primary cell wall
Besides supporting and protecting a cell the cell membrane Blank what enters and leaves the cell?
The membrane regulates what comes in and out of the cell.
What is the function of proteins and carbonhydrates that are embedded in a cell membrane?
they help control what enters and leaves the cell.
Cholesterol molecules and protein molecules help stabilize the cell membranes. Cholesterol prevents lower temperatures from inhibiting the fluidity of the membrane and prevents higher temperatures from increasing fluidity. Cholesterol is only found in animal cells.
Why is the plasma membrane called the selectively permeable membrane?
Let trans-membrane transport of molecules be either passive, or facilitated, or active: the plasma [bi-lipid layer] membrane has the power to exclude molecules It selects from passage through the Membrane into the Cell's interior.
... a receptor protein.
What indicates how easy it is for a substance to cross the plasma membrane?
Whether it's charged or not, hydrophilic, hydrophobic and its size.
What is the name of cell that contains 23 chromosomes and is only found in males?
I assume you are referring to humans. The cell is a sperm, or spermatozoan.
What molecules diffuses through the lipid portion of the plasma membrane?
Any hydrophobic ones. eg. steroids
