Cellular Organelles and Membrane Transport

These flashcards cover cellular organelles and membrane transport concepts, including structures and functions, emphasizing key terms and definitions.

Nucleus

Stores genetic information (DNA) and is the site of RNA synthesis.

Rough Endoplasmic Reticulum (Rough ER)

Membrane studded with ribosomes; site of membrane-bound and secreted protein synthesis.

Smooth Endoplasmic Reticulum (Smooth ER)

Folded, tubelike structure involved in detoxification, calcium storage, and lipid synthesis.

Golgi Complex

Membrane-bound structure that folds and chemically modifies synthesized proteins.

Ribosomes

Composed of rRNA and protein; involved in protein synthesis and can be bound or free.

Mitochondria

Double membrane organelles that are sites of oxidative phosphorylation and Krebs Cycle.

Chloroplast

Double membrane organelles; site of photosynthesis; includes thylakoid and stroma.

Lysosome

Membrane-enclosed sacs containing hydrolytic enzymes for intracellular digestion and apoptosis.

Vacuole

Membrane-bound sac for storage and release of macromolecules and cellular waste.

Plasma Membrane

Composed of phospholipids, membrane proteins, glycolipids/glycoproteins, and cholesterol.

Simple Diffusion

Passive transport of small, nonpolar molecules down their concentration gradient without the need for transport proteins.

Facilitated Diffusion

Passive transport of small molecules requiring transport proteins down their concentration gradient.

Active Transport

Requires energy input to transport molecules against their concentration gradient using carrier proteins.

Endocytosis

Import of materials into the cell through processes like phagocytosis and pinocytosis.

Exocytosis

Export of materials out of the cell, often involving the rough ER and Golgi complex.

Osmosis

Movement of water across a semipermeable membrane from a hypotonic to hypertonic solution.

Hypertonic Solution

Solution with high solute concentration and low free water concentration.

Isotonic Solution

Solution with equal solute and free water concentrations relative to another solution.

Hypotonic Solution

Solution with low solute concentration and high free water concentration.