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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
What types of cells found in plasma?
Red blood cells, white blood cells, and platelets are found in human blood.
Plasma membranes are a feature of?
Like all other cellular membranes, the plasma membrane consists of both lipids and proteins
Does Salmonella have a cell membrane?
Salmonella typhimurium does have a flagella, well actual multiple flagellums. A flagella is a whip like appendage on a cell to help it move and sense its surroundings.
What are the two chemicals that make up the cell membrane of a amoeba?
An amoeba is a single celled organisim which feeds by extending its body around and enveloping smalled organisms or materials, kind of like "the blob!" It is carbon based life so like most animals it is composed of a lipid membrane on the outside and DNA in its nucleus and all the other molecules that any other organic cell has in it. So to answer your question poorly, An amoeba is made up of organic, carbon based molecules.
Why would a substance not be able to pass through a membrane by diffusion?
Water cannot diffuse a plasma membrane because of the fact that the phosphate heads of the phospholipids are hydrophilic, the hydrocarbon tails of the phospholipids are hydrophobic, meaning they repel water. The bilayer phospholipid model of the plasma membrane shows that the phophates face outward on either side of the membrane and the lipid tails are in the middle of the bilayer.
What types of cells are surrounded by a cell membrane?
All cells are surrounded by a plasma membrane of some kind, but depending on the cell type they can also be surrounded by additional structures. Plant cells have a cell wall to maintain hydrostatic pressure and gram-positive bacteria have a thick coating of peptidoglycans surrounding their plasma membrane.
Why do all of the phases of mitosis happen at the same time in an onion root?
Different individual cells will have received slightly different amounts of vital nutrients at different times, therefore, mitosis will not occur at the same rate throughout the onion. Over time, cells will become more out-of-sync and end up mitozing at different times causing each cell to be at different stages of the mitotic cycle.
P.S. Is mitotic even a word - I've never heard it before. Sounds like a smug biology teacher made it up.
What statement best describes the role of the cell membrane?
The cell membrane controls what goes in an out of the cell.
How have bone cells adapted to their function?
It depends on what sort of bone cell you are talking about. Osteoblasts are specialized in so far as they form new bone only, osteoclasts digest bone for remodeling however cannot form new bone. However, there are other cells in bone, such as hemaotpoietic stem cells in the bone marrow that are only specialized in so far as they produce blood cells.
Which components is the most important in determining the fluidity of the cell membrane?
phospholipids and cholesterols
What is the difference between a plasma membrane and a Cell?
A plasma membrane is a structure that surrounds the cell and separates it from its environment, controlling the movement of substances in and out of the cell. A cell is the basic structural and functional unit of life, consisting of various organelles surrounded by the plasma membrane. Thus, a cell encompasses the plasma membrane within its boundaries.
How does the cytoplasm regulate?
No. The Endoplasmic Reticulum moves things throughout the cell, and the Cell Membrane controls what enters the cell, and what leaves. That means that the Cell Membrane is semi-permiable.
What functions to membrane proteins have?
The plasma membrane proteins have many functions. They pass on information through the membrane, they give the cell structural support and recognize different particles within the cell, and they are also transporters.
What part of the cell membrane make up the phospholipid bilayer?
Phosholipids are composed of a glycerol backbone, 2 fatty acids, and a phosphate group. Two fatty acid chains are attached to the first 2 carbon molecules of the glycerol chain. The 3rd carbon of the glycerol backbone is attached to a phosphate group.
What is the function of the carbohydrates that stick out if the plasma membrane?
The carbohydrates help identify chemical signals and define the characteristics of the cell.
What is a jelly like substance within the plasma membrane?
Cytoplasm is the jellylike material found within the cell membrane. This substance, which is made mostly of water, protects the organelles inside the cell, such as the Golgi body/apparatus, endoplasmic reticulum, and the nucleus.
What are enzymes inside of cells called?
Enzymes are proteins, which are comprised of chains of amino acids. All enzymes are proteins (but not all proteins are enzymes)
In a plasma membrane how do the tails of the phospholipid molecules lineup?
they are sandwiched between two layers of heads
What pumps in the cell membrane?
The sodium potassium pump is a form of active transport in which sodium and potassium end up switching places (one into the cell and one leaves the cell). The pump is located in the cell membrane.
How is plasma related to gases?
Plasma and gas are two of the four states of matter. The others are liquid and solid.
