Which of the following best describes the cell membrane?
Which of the following best describes the cell membrane?
The correct answer is (C) A flexible lipid double layer. The cell membrane is often referred to as a “fluid mosaic,” a flexible structure…
Which answer best describes the primary function of the cell membrane?
The cell membrane has numerous functions, but its primary role is to keep organelles contained within the cell. The cell membrane’s primary function is to move waste out of the cell.
What is the main purpose of the cell membrane?
Cell membranes protect and organize cells. All cells have an outer plasma membrane that regulates not only what enters the cell, but also how much of any given substance comes in.
Which best describes the general structure of the plasma cell membrane?
It is composed of phospholipid bilayer structure with embedded proteins. The membrane proteins help in transportation of water, ions and solute across the membrane and thus provide semi permeability to the membrane. Thus, the correct answer is option B.
Which example involves a cell membrane?
The right answer is B. The membrane plays an important role in communication (signal transmission) within the body. In the nervous system, neurons communicate with each other and with effector cells (such as muscle cells) through specialized contacts called synapses.
Which best describes the role of the mitochondrion?
Known as the “powerhouses of the cell,” mitochondria produce the energy necessary for the cell’s survival and functioning. In addition to producing energy, mitochondria store calcium for cell signaling, generate heat, and are involved in cell growth and death.
What is the function of the Golgi apparatus?
The Golgi apparatus, or Golgi complex, functions as a factory in which proteins received from the ER are further processed and sorted for transport to their eventual destinations: lysosomes, the plasma membrane, or secretion. In addition, as noted earlier, glycolipids and sphingomyelin are synthesized within the Golgi.
What are 3 functions of the cell membrane?
Biological membranes have three primary functions: (1) they keep toxic substances out of the cell; (2) they contain receptors and channels that allow specific molecules, such as ions, nutrients, wastes, and metabolic products, that mediate cellular and extracellular activities to pass between organelles and between the …
What are the two functions of the cell membrane?
The cell membrane, therefore, has two functions: first, to be a barrier keeping the constituents of the cell in and unwanted substances out and, second, to be a gate allowing transport into the cell of essential nutrients and movement from the cell of waste products.
Which model best describes the observations and functions of the plasma membrane?
In 1972, S.J. Singer and Garth L. Nicolson proposed a new model that provides microscopic observations and better explains plasma membrane function. The explanation, the fluid mosaic model, has evolved somewhat over time, but it still best accounts for plasma membrane structure and function as we now understand them.
What is the description of cell membrane?
The cell membrane, also called the plasma membrane, is found in all cells and separates the interior of the cell from the outside environment. The cell membrane consists of a lipid bilayer that is semipermeable. The cell membrane regulates the transport of materials entering and exiting the cell.
Which best describes the permeability of a membrane?
Answer: the answer is D: The ability to allow materials to cross a membrane.
What is the role of the cell membrane?
The cell membrane contains genetic information of the cell The cell membrane provides support and protection for the cell The cell membrane is where protein molecules are manufactured in the cell The cell membrane regulates the movement of materials in and out of the cell.
How does the plasma membrane mediate cellular processes?
The plasma membrane mediates cellular processes by regulating the materials that enter and exit the cell. The plasma membrane carries markers that allow cells to recognize one another and can transmit signals to other cells via receptors. plasma membrane: The semipermeable barrier that surrounds the cytoplasm of a cell.
Why does the plasma membrane have to be flexible?
Plasma membranes must be very flexible in order to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries.
How is the cell membrane an impermeable barrier?
The cell membrane is an impermeable barrier that prevents water from entering the cell. The cell membrane allows solutes to enter the cell, which causes the cell to shrink. The cell membrane allows water to enter and leave the cell. The cell membrane removes solutes from the environment.
Which is the best model of the cell membrane?
4. Fluid Mosaic Model: The fluid mosaic model of cell membrane was proposed in 1972 by S.J. Singer and G.L. Nicolson. According to this model, the cell membranes have been visualised as mosaics of lipids and proteins.
The cell membrane contains genetic information of the cell The cell membrane provides support and protection for the cell The cell membrane is where protein molecules are manufactured in the cell The cell membrane regulates the movement of materials in and out of the cell.
How is the fluid mosaic model of the cell membrane described?
The fluid mosaic model of the cell membrane is how scientists describe what the cell membrane looks and functions like, because it is made up of a bunch of different molecules that are distributed across the membrane.
Who was the first to create a membrane model?
This conclusion led James Danielli and Hugh Davson in 1935 to suggest bimolecular leaflet model of cell membrane. Danielli and Davson model was the first attempt to describe membrane structure in terms of molecules and to relate the structure to biological and chemical properties.