top of page

Eukaryotic Cells

Every organism you have ever seen with the naked eye was made of eukaryotic cells.  Eukaryotic cells have internal membranes that create organelles with specific functions. 

  • Membrane-bound organelles (cell parts) include the: 

    • Nucleus​

    • Mitochondria

    • Endoplasmic Reticulum (ER)

    • Golgi Apparatus

    • Lysosome

    • Chloroplast

    • Vacuole

  • Eukaryotes and prokaryotes also have some similar organelles​:

    • Ribosomes​

    • Cell Membrane

    • Cell Wall (structurally different)

  • By compartmentalizing their different functions, eukaryotes can work more efficiently. 

    • For example, a lysosome can digest proteins while a ribosome is building other proteins. 

​

Organelles

Cells have specialized parts that do specific things.  The following are found in most eukaryotic cells.

  • Cell Membrane - control what goes in and out of the cell

    • Made of a phospholipid bilayer​ that doesn't mix with water

    • Embedded proteins allow substances to pass through

      • Channel Proteins -  thin tubes that allow ​small molecules to pass through but not large ones.

      • Transport Proteins - gates that allow larger molecules to pass through; can be active or passive.

  • Mitochondria​​ - makes ATP during cellular respiration (converts food energy into cellular energy)

  • Nucleus - holds and protects the DNA which codes for the proteins that make up the cell

  • Ribosomes - link amino acids to make proteins (actually polypeptides)

  • Endoplasmic Reticulum - internal membrane that houses the ribosomes making proteins; also makes lipids and breaks down toxins

  • Golgi Apparatus - combines polypeptides to make proteins and distributes them in/out of the cell

  • Lysosomes - small sacs of digestive enzymes used mostly to break down food in animals but also assist in breakdown of oils and toxins in plants and sometimes apoptosis - programmed cell death.

  • Cytoplasm - the fluid between all of the other organelles; allows for diffusion/transport within the cell

In plant cells only:​

  • Chloroplast - site of photosynthesis; process of converting light energy into cellular energy of food.

  • Vacuole - large sac used for water storage

  • Cell Wall - rigid structure outside of the cell membrane that gives support and helps cells maintain their shape.

    • Made of cellulose in plants​

    • Made of chitin in fungi

In animal cells only:​

  • Centrioles - assist in cell division

  • Cilia - small hair-like structures on the outside of some cells used for movement

    • "movement" can mean the cell moving through a liquid or liquid moving over the cell​

  • Flagella - long tail-like structure on the outside of some cells used for movement​

Plant Cell.png
bottom of page