CELL

Transport mechanisms

Means by which substances from the blood enter the cell

Diffusion

Passive process of random movement in net movement driven by kinetic energy

Facilitated diffusion

Assists a specific substance using carrier proteins, moving higher to lower concentration

Channel-mediated facilitated diffusion

Solute movement down its concentration gradient through ion channels

Secondary Active Transport

Establishes an ion concentration gradient using energy stored in ionic concentration gradient

Exocytosis

Release of content outside the cell requiring ATP, for proteins and water-soluble substances

Active transport

Transport against concentration gradient requiring ATP and specific carrier proteins

Primary Active transport

Derived from hydrolysis of ATP, "pumps" substances against concentration gradient

Secondary active transport

Uses energy stored in an ionic concentration gradient, indirectly utilizing ATP

Phagocytosis

Engulfing large solid particles by phagocytes like macrophages and neutrophils

Exocytosis

Release of substances into the extracellular fluid by secretory cells and nerve cells

Osmosis

Net movement of solvent through a selectively permeable membrane from higher to lower concentration

Peroxisome

Organelle that breaks down hydrogen peroxide and degrades lipids and amino acids

Nucleus

Control center of the cell enclosed by a nuclear envelope, containing chromatin and nucleolus

Plasma membrane

Outer boundary of the cell controlling entry and exit, composed of phospholipids and cholesterol

Ribosome

Site of protein synthesis, either free in the cytoplasm or attached to the rough endoplasmic reticulum

Golgi apparatus

Modifies, packages, and distributes proteins and lipids for secretion in flattened membrane sacs

Lysosome

Contains digestive enzymes for breaking down cellular waste and foreign materials

Mitochondria

Organelle responsible for ATP synthesis when oxygen is available, with inner membrane cristae

Vesicular transport

Mechanism involving endocytosis and exocytosis for cellular material movement