A plant cell is defined as a cell which has a nucleus and organelles bounded by a thick and rigid cell wall. Within this rigid cell wall, there are chloroplast organelles containing chlorophyll. Chlorophyll converts sunlight into energy and gives plant cells their green color.
Evolution of the Plant Cell
Now in order to truly understand plant cells, let’s go back a very long time ago to when Earth was just formed. Millions of years pass and cells evolve. These first cells didn’t have a nucleus and were very simple structures, but they were alive. We call these cells prokaryotes, which still exist today.
More millions of years go by and one day a prokaryotic cell engulfed another and they learned to survive together and replicant. The cell that was engulfed became the nucleus and began contributing to its host. This evolution created a whole new group of cells known as eukaryotic cells, which have a nucleus contained within its membrane.
Eventually, eukaryotic cells had formed a rigid cell wall and the ability to turn sunlight into energy. These cells became known as plant cells. You can still see them working today in the leaves on our trees or the vegetables on your table.
Plant Cell Diagram
Shown below is a plant cell model. Notice the nucleus and all the organelles are all contained within the rigid cell membrane. Remember this is just a cartoon illustration. These organelles look much different when looking at a cell under a microscope. Also, start memorizing each organelle name and what they look like. This will help out a bunch, once we start looking at each organelle individually.
Plant Cell Organelles
Listed below is a summary of plant cell organelles and their primary function within the cell. Click on each link to learn more about each organelle and what they look like.
- Cell Membrane – Protects the cell and regulates molecules entering and leaving the cell
- Cell Wall – Main protection barrier of plant cells
- Cytoplasm – Helps hold the cell’s organelles in place
- Cytoskeleton – Provides structural support for the cell
- Chloroplast – Converts sunlight to energy by a process called photosynthesis
- Nucleus – Stores the DNA and coordinates the cell’s activities, basically, it is the brain
- Ribosomes – Build protein for the cell to use
- Lysosomes – Break down waste into simple compounds for other organelles to use
- Mitochondria – Convert oxygen and nutrients into energy
- Endoplasmic Reticulum – Manufactures and transports chemical compounds to and from the nucleus
- Golgi Apparatus – Modifies proteins and fats built in the cell and prepares them for storage or transports them outside the cell
- Peroxisomes – Digest toxic materials in the cell
- Vacuole – Stores waste products and maintains the PH level of the cell
- Plasmodesmata – Enables transport of material and communication to adjacent cells
- Vesicle – Transports materials within the cell and help store enzymes