Cell Transport

Front

What is facilitated diffusion?

Back

Facilitated diffusion is a process by which substances move across a cell membrane with the help of transport proteins, without the use of energy. It is commonly used for molecules like glucose.

Front

Define osmosis.

Back

Osmosis is the diffusion of water across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Front

What are molecular pumps?

Back

Molecular pumps are membrane proteins that use energy (usually from ATP) to transport ions or molecules against their concentration gradient.

Front

What happens to a cell in a hypertonic solution?

Back

In a hypertonic solution, a cell will shrink as water moves out of the cell to balance the solute concentration outside.

Front

What is exocytosis?

Back

Exocytosis is the process by which a cell expels materials, such as neurotransmitters, by vesicles fusing with the plasma membrane.

Front

What is simple diffusion?

Back

Simple diffusion is the movement of small or nonpolar molecules across the cell membrane without the need for energy or transport proteins.

Front

Explain the term 'semi-permeable membrane'.

Back

A semi-permeable membrane is a barrier that allows certain substances to pass through while blocking others, often based on size or charge.

Front

What is the role of transport proteins in cell transport?

Back

Transport proteins facilitate the movement of substances across the cell membrane, either by providing a passageway for molecules or by actively transporting them.

Front

Define hypertonic, hypotonic, and isotonic solutions.

Back

Hypertonic: Higher solute concentration outside the cell; causes cell to shrink. Hypotonic: Lower solute concentration outside the cell; causes cell to swell. Isotonic: Equal solute concentration inside and outside the cell; no net movement of water.

Front

What is the difference between active and passive transport?

Back

Active transport requires energy to move substances against their concentration gradient, while passive transport does not require energy and moves substances along their gradient.