Cell Transport and Energy Concepts Flashcards

A set of 25 vocabulary flashcards covering membrane transport mechanisms, thermodynamics, and energy processes in cells.

Active transport

A process in which a cell must expend energy to move a solute against its concentration gradient—that is, across a membrane toward the side where the solute is more concentrated.

Exocytosis

The process used by a cell to export bulky materials such as proteins or polysaccharides, where a transport vesicle buds from the Golgi apparatus, moves to the edge of the cell, fuses with the plasma membrane, and spills its contents outside.

Transport vesicle

A vesicle that buds from the Golgi apparatus, moves to the edge of the cell, fuses with the plasma membrane, and releases its contents outside while adding its membrane to the plasma membrane.

Endocytosis

A transport process through which a cell takes in large molecules or droplets of fluid.

Phagocytosis

Also known as 'cellular eating,' a process where a cell engulfs a particle by wrapping extensions called pseudopodia around it and packaging it within a membrane-enclosed sac called a vacuole.

Pseudopodia

Extensions that a cell wraps around a particle during phagocytosis to engulf it.

Vacuole

A membrane-enclosed sac within which a cell packages an engulfed particle during phagocytosis.

Receptor-mediated endocytosis

A process that enables a cell to acquire specific solutes when receptor proteins in specific regions of the membrane (lined by coat proteins) pick up particular molecules from the extracellular fluid as a coated pit pinches closed to form a vesicle.

Coated pit

A specific membrane region lined by coat proteins that pinches closed to form a vesicle during receptor-mediated endocytosis.

Energy

The capacity to cause change, especially to do work.

Kinetic energy

The energy of motion.

Thermal energy

A type of kinetic energy associated with the random movement of atoms or molecules.

Heat

Thermal energy in transfer from one object to another.

Potential energy

The second main form of energy; energy that matter possesses as a result of its location or structure.

Chemical energy

The potential energy available for release in a chemical reaction.

Thermodynamics

The study of energy transformations that occur in a collection of matter.

First law of thermodynamics

Also known as the law of energy conservation, it states that the energy in the universe is constant; energy can be transferred and transformed, but it cannot be created or destroyed.

Entropy

A quantity used by scientists as a measure of disorder, or randomness.

Second law of thermodynamics

The law stating that every energy conversion increases the entropy (disorder) of the universe.

Cellular respiration

The process in which oxygen is used in reactions that release energy from fuel molecules, where the chemical energy stored in organic molecules is used to produce ATP to perform work.

Exergonic reaction

A reaction that releases energy ('energy outward'), beginning with reactants whose covalent bonds contain more potential energy than those in the products.

Endergonic reactions

Reactions that require a net input of energy and yield products that are rich in potential energy ('energy inward').

Metabolism

The total of an organism's chemical reactions.

Metabolic pathway

A series of chemical reactions that either builds a complex molecule or breaks down a complex molecule into simpler compounds.

Energy coupling

The use of energy released from exergonic reactions to drive endergonic reactions.

Active transport

A process in which a cell must expend energy to move a solute against its concentration gradient, across a membrane toward the side where the solute is more concentrated.

Exocytosis

The process used by a cell to export bulky materials such as proteins or polysaccharides, where a transport vesicle buds from the Golgi apparatus, moves to the edge of the cell, fuses with the plasma membrane, and spills its contents outside.

Endocytosis

A transport process through which a cell takes in large molecules or droplets of fluid.

Phagocytosis

Also known as 'cellular eating,' a process where a cell engulfs a particle by wrapping extensions called pseudopodia around it and packaging it within a membrane-enclosed sac called a vacuole.

Pseudopodia

Cellular extensions that a cell wraps around a particle during phagocytosis to engulf it.

Vacuole

A membrane-enclosed sac in which a cell packages an engulfed particle during the process of phagocytosis.

Receptor-mediated endocytosis

A process that enables a cell to acquire specific solutes when receptor proteins in specific regions of the membrane pick up particular molecules from the extracellular fluid as a coated pit pinches closed to form a vesicle.

Coated pit

A specific region of the membrane lined by coat proteins that pinches closed to form a vesicle during receptor-mediated endocytosis.

Energy

The capacity to cause change, especially to do work.

Kinetic energy

The energy of motion.

Thermal energy

A type of kinetic energy associated with the random movement of atoms or molecules.

Heat

Thermal energy in transfer from one object to another.

Potential energy

The second main form of energy; energy that matter possesses as a result of its location or structure.

Chemical energy

The potential energy available for release in a chemical reaction.

Thermodynamics

The study of energy transformations that occur in a collection of matter.

First law of thermodynamics

Also known as the law of energy conservation; states that the energy in the universe is constant, meaning it can be transferred and transformed, but cannot be created or destroyed.

Entropy

A quantity used by scientists as a measure of disorder, or randomness.

Second law of thermodynamics

The law stating that every energy conversion increases the entropy (disorder) of the universe.

Cellular respiration

The process in which oxygen is used in reactions that release energy from fuel molecules, where chemical energy stored in organic molecules is used to produce ATP to perform work.

Diffusion

A transport phenomenon across a membrane resulting in equal concentrations of solute, which is a more disordered arrangement (higher entropy) than having uneven concentrations on opposite sides.

Exergonic reaction

A reaction that releases energy ('energy outward'), beginning with reactants whose covalent bonds contain more potential energy than those in the products.

Endergonic reactions

Reactions that require a net input of energy and yield products that are rich in potential energy ('energy inward').

Metabolism

The total of an organism's chemical reactions.

Metabolic pathway

A series of chemical reactions that either builds a complex molecule or breaks down a complex molecule into simpler compounds.

Energy coupling

The use of energy released from exergonic reactions to drive endergonic reactions.