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Introduction: For large polar molecules and ions, there are special protein called transport protein through which they cross the lipid bilayer. Some transport proteins form pores. Others are gated that close in response to a stimulus. Active transport is a transport where protein pumps a solute across a cell membrane against the solutes concentration gradient which requires energy. Passive transport does not need energy for transport to occur. Facilitated diffusion is a type of passive transport in which solute follows its concentration gradient across a membrane by moving through a transport protein. Osmosis is an example of passive transport, a membrane-crossing mechanism that requires no energy input.
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- Facilitated transport differs from diffusion in that facilitated diffusiona. involves the passive use of a carrier protein.b. involves the active use of a carrier protein.c. moves a molecule from a low to a high concentration.d. involves the use of ATP molecules.arrow_forwardWhich of these statements about carrier-mediated facilitated diffusion is true? a. It uses cellular ATP. b. It is used for cellular uptake of blood glucose. c. It is a form of active transport. d. None of these are true.arrow_forwardActive transport of a substance across a membrane requiresa. a gradient b. the expenditure of ATP c. water d. diffusionarrow_forward
- You find a membrane protein that moves molecules across a membrane. What type of transport could that protein be involved in?arrow_forwardWhen cellular transport through the plasma membrane must be provided with energy in form of ATP to power the transport process, what is this called? A. Selective permeability B. Passive transport C. Active transport D. Diffusionarrow_forwardFacilitated diffusion differs from active transport in thatfacilitated diffusiona. expends no ATP.b. moves molecules from an area of higher concentration toone of lower concentration.c. does not require a carrier protein for transport.d. moves molecules in vesicles across a semipermeablemembrane.arrow_forward
- A transport protein requires ATP to pump sodium ions across a membrane. This is a case of_______ . a. passive transport c. osmosis b. active transport d. facilitated diffusionarrow_forwardWhich of these junctions allows solutes and water to pass directly from one cell to another, without interacting with the ECM? a. Adherens junctions b. Gap junctions c. Con junctions d. Tight junctionsarrow_forwardWhich of the following processes requires protein carriers to move materials up their concentration gradient? ____ a. active transport ____ b. osmosis ____ c. endocytosis ____ d. facilitated diffusionarrow_forward
- The cytoplasmic connections from cell to cell are known as: A middle lamella B plasmodesmata C cell membrane system D endoplasmic reticulumarrow_forwardWhich of the following is incorrect regarding facilitated diffusion?a. It is a passive process.b. It allows the movement of molecules from areas of lowconcentration to areas of high concentration.c. It may use either channel or carrier proteins.d. It allows the rapid transport of glucose across the membrane.arrow_forwardOne substance flows down its concentration gradient, and the energy is harnessed to move another substance up its gradient in the same direction. This best describes a. primary active transport. b. endocytosis. c. symport secondary active transport. d. antiport secondary active transport.arrow_forward
- Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning