The cell membrane’s primary purpose is to contain the contents of the cell and provide structural integrity to the entire unit. Additionally, the cell membrane must allow resources, such as water and oxygen, to permeate the membrane while excluding harmful objects from entering the cell. The cell membrane is made up of a phospholipid bilayer. Additionally, the cell membrane serves as the attachment site for some cell components.Know More
Cell membranes are common to most forms of life. Prokaryotes, fungi, plants and animals all have membrane-bound cells. Additionally, some cells, like those of plants, have another type of barrier, called the cell wall. Most other life forms lack cell walls.
Cell membranes permit substances to enter or exit the cell through the process of diffusion. The cell membrane’s bilayer is constructed of paired molecules that have both water-repellant and water-soluble ends. When lined up to form a cell membrane, the water-soluble ends face outward, while the water-repellent sides face each other.
Proteins also help provide the structure of the cell membrane. Some of these proteins sit on the outside of the cell membrane and work as receptor cells. These cells exist only to detect the presence of various chemicals, which will cause the cell to react accordingly, when they are detected.Learn more in Cells
Unlike the cell membrane, the cell wall is not common to all types of cells. A protective layer that surrounds the cell membrane, one of its main functions is to prevent over-expansion of a cell.Full Answer >
The discovery of the cellular membrane was made by Carl Naegeli and C. Cramer in 1855. Their discovery provided important insight into many unanswered questions within the field of biology.Full Answer >
If the cell membrane becomes totally impermeable, water and dissolved gases, most notably oxygen, would no longer be able to enter or leave the cell. The cell membrane is usually permeable to a number of substances, mostly small, nonpolar molecules. Other polar or charged particles are transported across the membrane by special embedded protein structures, and so would not be directly affected by a change in membrane permeability.Full Answer >
The cell membrane is a semipermeable lipid bilayer that surrounds the cytoplasm of all cells. In animal cells, it is the outermost layer of the cell. In plants, fungi and some bacteria, a cell wall surrounds the cell membrane to form the cell's outermost layer.Full Answer >