Introduction to Membrane Transport definitions Flashcards

Movement of molecules across a cell membrane, either passively without energy or actively with energy, through selective permeability, allowing specific molecules to pass while blocking others.

Semi-permeable barriers that selectively allow certain molecules to pass while blocking others, crucial for maintaining cellular homeostasis and facilitating specific transport processes.

A membrane that allows certain molecules to pass through while blocking others, based on size, charge, or solubility, ensuring selective permeability.

A membrane property allowing selective passage of certain molecules while blocking others, based on size, charge, or solubility.

Movement of molecules from an area of high concentration to an area of low concentration without the need for energy or transport proteins.

A positively charged ion that cannot freely cross the cell membrane due to its charge and size, requiring specific transport proteins to move across biological membranes.

A diatomic molecule essential for respiration, small and nonpolar, easily diffuses across cell membranes without the need for transport proteins.

A double-layered structure of phospholipids forming the core of cell membranes, with hydrophobic tails inward and hydrophilic heads outward, regulating molecule passage selectively.

Amphipathic molecules with hydrophilic heads and hydrophobic tails, forming the bilayer of cell membranes, crucial for selective permeability and membrane fluidity.

Repels water and does not mix with it, often due to nonpolar characteristics, making it unable to interact with polar molecules like water.

Attracted to water, these molecules or substances can form hydrogen bonds with water, allowing them to dissolve or interact easily in aqueous environments.

Molecules with uneven distribution of charges, resulting in partial positive and negative regions, making them hydrophilic and less likely to pass through the hydrophobic lipid bilayer of cell membranes.

A small, nonpolar gas molecule that easily diffuses through cell membranes without the need for transport proteins.

The process by which cells engulf external substances, forming vesicles to internalize them, often for nutrient uptake or defense.

A process where a cell engulfs large particles or microorganisms by extending its membrane around them, forming a vesicle that is then internalized.