Brush border | Centrioles |
Centrosomes | Cilia |
Cylindrical structures involved in organizing microtubules and cell division. | A dense layer of microvilli on the surface of certain cells, increasing surface area for absorption. |
Hair-like projections on the surface of some cells that move fluids or particles. | The region near the nucleus that contains centrioles and helps organize the cytoskeleton. |
Cytoplasm | Cytoskeleton |
Cytosol | Extracellular fluid |
A network of protein filaments that provide structure, shape, and movement to cells. | The gel-like substance within a cell that contains organelles and cytosol. |
Fluid found outside of cells, including interstitial fluid and plasma. | The fluid portion of the cytoplasm, excluding organelles. |
Flagella | G protein |
Glycocalyx | Glycolipid |
A signaling molecule that helps transmit signals from receptors to intracellular pathways. | Long, whip-like structures used by some cells (e.g., sperm) for movement. |
A lipid with a carbohydrate attached, playing a role in cell recognition. | A sugar-rich coating on the surface of cells that provides protection and cell recognition. |
Glycoprotein | Golgi complex |
Interstitial fluid | Intracellular fluid |
An organelle that modifies, sorts, and packages proteins and lipids for transport. | A protein with a carbohydrate chain attached, important for cell signaling. |
The fluid inside a cell, primarily composed of cytosol. | The fluid surrounding cells within tissues. |
Lysosome | Macrophage |
Microvilli | Mitochondria |
A type of immune cell that engulfs and digests pathogens, debris, and dead cells. | An organelle filled with digestive enzymes that break down waste and cellular debris. |
Organelles responsible for ATP production through cellular respiration. | Tiny finger-like projections on some cells that increase surface area for absorption. |
Nucleus | Nuclear pore |
Nuclear envelope | Peroxisome |
Openings in the nuclear envelope that allow substances to move between the nucleus and cytoplasm. | The control center of the cell that contains DNA and directs cellular activities. |
An organelle involved in breaking down fatty acids and detoxifying harmful substances. | A double membrane that surrounds the nucleus and separates it from the cytoplasm. |
Plasma membrane | Receptor protein |
Ribosomes | Rough endoplasmic reticulum |
A membrane protein that binds to specific molecules (ligands) and triggers a response. | The outer boundary of a cell that controls what enters and exits. |
A membrane network covered in ribosomes that produces and processes proteins. | Small structures responsible for protein synthesis, either free-floating or attached to the rough ER. |
Smooth endoplasmic reticulum | Vesicle |
Antiport | Aquaporin |
A small, membrane-bound sac that transports substances within the cell. | A membrane network involved in lipid synthesis, detoxification, and calcium storage. |
A membrane protein that forms water channels, allowing rapid water transport across cell membranes. | A type of membrane transport in which two substances move in opposite directions across a membrane. |
Carrier protein | Carrier-mediated transport |
Cotransport | Endocytosis |
A form of membrane transport that relies on specific proteins to move substances. | A membrane protein that binds to and transports substances across the cell membrane. |
The process of a cell engulfing material by wrapping its membrane around it. | The simultaneous transport of two substances across a membrane by a single protein. |
Exocytosis | Facilitated diffusion |
Hydrostatic pressure | Hypertonic |
The passive transport of substances across a membrane using transport proteins. | The process of expelling materials from a cell via vesicles that fuse with the plasma membrane. |
A solution with a higher solute concentration than the inside of a cell, causing water to leave the cell. | The pressure exerted by a fluid in a confined space, such as blood pressure. |
Hypotonic | Integral protein |
Isotonic | Leak channel |
A membrane protein embedded within the lipid bilayer, often spanning the entire membrane. | A solution with a lower solute concentration than the inside of a cell, causing water to enter the cell. |
A membrane protein channel that allows ions to move freely down their concentration gradient. | A solution with the same solute concentration as the inside of a cell, maintaining equilibrium. |
Ligand-gated channel | Osmolarity |
Osmosis | Osmotic pressure |
A measure of solute concentration in a solution. | A membrane protein channel that opens or closes in response to a specific chemical signal. |
The force exerted by water moving across a membrane due to osmosis. | The movement of water across a selectively permeable membrane from a lower solute concentration to a higher one. |
Peripheral protein | Phagocytosis |
Pinocytosis | Primary active transport |
A type of endocytosis in which a cell engulfs large particles or microorganisms. | A protein located on the surface of the cell membrane, not embedded within it. |
Transport that requires ATP to move substances against their concentration gradient. | A type of endocytosis in which a cell takes in fluid and small dissolved substances. |
Receptor-mediated endocytosis | Secondary active transport |
Selectively permeable | Simple diffusion |
Transport that relies on an ion gradient created by primary active transport to move substances. | A selective form of endocytosis where receptors on the membrane help capture specific molecules. |
The passive movement of molecules across a membrane without the use of transport proteins. | A membrane that allows some substances to pass while blocking others. |
Sodium-potassium pump | Symport |
Tonicity | Transmembrane protein |
A type of cotransport in which two substances move in the same direction across a membrane. | A transport protein that moves sodium out of the cell and potassium into the cell using ATP. |
A protein that spans the entire cell membrane and is involved in transport or signaling. | The ability of a solution to affect the water balance in a cell. |
Uniport | Voltage-gated channel |
W3 | W4 |
A membrane channel that opens or closes in response to changes in electrical charge. | A type of transport in which a single substance moves in one direction across a membrane. |
D4 | D3 |