14C Active Transport across Membranes

These flashcards cover key vocabulary and concepts related to active transport mechanisms including primary and secondary active transport, relevant proteins, and their physiological significance.

Active Transport

The process of moving molecules across a membrane against their concentration gradient, requiring energy from ATP.

Primary Active Transport

Transport directly fueled by the hydrolysis of ATP.

P-type ATPase

A type of ATPase that gets phosphorylated during transport and is primarily responsible for maintaining ion gradients.

ABC Transporters

A large family of transport proteins that utilize ATP to transport various substances, including drugs and lipids.

Conformational Change

A structural change in a protein that enables it to perform its function, often driven by ATP.

Sarcoplasmic Reticulum

An organelle that stores calcium ions in muscle cells.

Calcium Gradient

The difference in calcium ion concentration inside and outside the cell, important for muscle contraction.

Phosphorylation

The addition of a phosphate group to a molecule, often leading to a change in protein function.

De-Phosphorylation

The removal of a phosphate group from a molecule, which can reverse the action of phosphorylation.

Na+/K+ ATPase

An enzyme that pumps sodium out of the cell and potassium into the cell against their concentration gradients.

Gastric H+/K+ ATPase

An enzyme that exchanges hydrogen ions for potassium ions in the stomach lining, regulating stomach acidity.

Digitalis

A drug that inhibits the Na+/K+ pump, increasing intracellular calcium and helping diagnose heart conditions.

Ouabain

A cardenolide that inhibits the Na+/K+ ATPase, affecting heart function.

E1 State

The conformation of the Na+/K+ pump that is open to the cytoplasm.

E2 State

The conformation of the Na+/K+ pump that is open to the outside of the cell.

Secondary Active Transport

Transport that is driven by the energy of another molecule moving down its concentration gradient.

Symporter

A type of cotransporter that moves two molecules in the same direction across a membrane.

Antiporter

A type of cotransporter that moves two molecules in opposite directions across a membrane.

Cystic Fibrosis

A genetic disorder caused by defects in an ABC Cl- ion transporter, leading to mucus build-up in the lungs.

Proton Pump Inhibitors

Medications that block the gastric proton pump to reduce stomach acid production.

Glucose/Na+ Symporter

A secondary active transport mechanism in the intestine that utilizes the Na+ gradient to absorb glucose.

Flippase

A type of P-type ATPase that helps transport lipids across membranes.

Ion Gradients

Differences in ion concentrations across membranes, crucial for the function of cells and transport mechanisms.

Amino Acids Transport

The process of moving amino acids across membranes, often facilitated by specific transporters.

Bile Salts Transport

The movement of bile salts through membranes via transport proteins to aid in digestion.

Multi-drug Resistance

A phenomenon where certain ABC transporters expel a variety of drugs, making infections harder to treat.