Compare the structures that make cells work
The nucleus holds most cellular DNA. The cytoplasm includes the cytosol and structures outside the nucleus. Select a cell type, then match each numbered marker to its role. Choose an organelle name to explore its record.
Compare the shared eukaryotic plan with features that distinguish plant cells.
Typical animal cell; organelle abundance and exact arrangement vary by cell type. Both schematics are simplified, magnified, and not to scale. Markers match the structure guide below.
Plasma membrane
A thin, flexible boundary that controls exchange with the surroundings.
Cytoplasm
The region between the plasma membrane and nucleus: cytosol plus organelles and other structures.
Nucleus and nuclear envelope
Most cellular DNA is inside this compartment, which has a double membrane and nuclear pores.
Nucleolus
A dense region inside the nucleus where ribosomal components are assembled.
Rough endoplasmic reticulum
Membrane sheets continuous with the nuclear envelope; bound ribosomes make many secreted and membrane proteins.
Smooth endoplasmic reticulum
A connected ER region without bound ribosomes; it supports lipid synthesis and other cell-specific jobs.
Golgi apparatus
Stacks of flattened membrane sacs that modify and sort many proteins and lipids.
Mitochondrion
A double-membrane organelle; folds of its inner membrane are called cristae.
Ribosomes
Molecular machines that build proteins; some are free in the cytosol and others bind the rough ER.
Transport vesicles
Small membrane-bound carriers that move selected cargo between compartments.
Lysosome
An acidic compartment that breaks down selected material for recycling; abundance varies by cell type.
Peroxisome
A compartment for specialized oxidation reactions, including some steps in lipid metabolism.
Cytoskeleton
Protein filaments and tubes that help organize shape, movement, and intracellular transport.
Centrosome
A common animal-cell microtubule-organizing center; it is not found in every eukaryotic cell type.