endocytosis
Membrane engulfs outside
Endocytosis is the process by which a cell takes in material from outside by engulfing it with its membrane.
The cell membrane folds inward, surrounds the substance, and pinches off to form a small internal sac called a vesicle.
Cells use endocytosis to absorb nutrients, capture pathogens, and regulate surface receptors.
The opposite process—releasing material—is exocytosis.
Small fluid-filled sac
- membraneThin tissue sheet
- invaginationInfolding of tissue layers
- fissionNuclear breakup releasing energy
- receptor-mediatedInitiated through surface binding
engulfment · internalization · uptake · actin · cytoskeleton · microtubule · phospholipid
Digestive organelle in cells
- cytoplasmGel surrounding the nucleus
- sortingArranging into sequence
- traffickingIllegal transport for profit
- degradationDecline in condition
Engulfing immune cell
- neutrophilMulti-lobed immune cell
- engulfmentComplete surrounding and absorption
- pathogenDisease-causing microorganism
- bacteriaNucleus-free single-celled organisms
immunity · innate · antigen · inflammation · monocyte · particle · microbe · debris
Molecule that binds centrally
- receptor-mediatedInitiated through surface binding
- signalMessage-conveying cue
- bindingLegally or morally required
- specificityExactness of detail
LDL · insulin · cholesterol · iron · selective · affinity · downregulation
Vesicular release from cells
- secretionSubstance released by glands
- transporterOne who conveys cargo
- intracellularWithin cell membranes
- cargoTransported goods
macromolecule · nutrient · protein · import · export · bidirectional
Substance absorbed by solvent
- dissolvedDispersed into solvent
- nonselectiveWithout preference or distinction
- constitutiveForming essential structure
- samplingExtracting subset for study
vesicle
Small fluid-filled sac
- membraneThin tissue sheet
- invaginationInfolding of tissue layers
- fissionNuclear breakup releasing energy
receptor-mediated · engulfment · internalization · uptake · actin · cytoskeleton · microtubule · phospholipid
lysosome
Digestive organelle in cells
- cytoplasmGel surrounding the nucleus
- sortingArranging into sequence
- traffickingIllegal transport for profit
macrophage
Engulfing immune cell
- neutrophilMulti-lobed immune cell
- engulfmentComplete surrounding and absorption
- pathogenDisease-causing microorganism
bacteria · immunity · innate · antigen · inflammation · monocyte · particle · microbe · debris
ligand
Molecule that binds centrally
- receptor-mediatedInitiated through surface binding
- signalMessage-conveying cue
- bindingLegally or morally required
specificity · LDL · insulin · cholesterol · iron · selective · affinity · downregulation
exocytosis
Vesicular release from cells
- secretionSubstance released by glands
- transporterOne who conveys cargo
- intracellularWithin cell membranes
cargo · macromolecule · nutrient · protein · import · export · bidirectional
solute
Substance absorbed by solvent
- dissolvedDispersed into solvent
- nonselectiveWithout preference or distinction
- constitutiveForming essential structure