Prokaryotes and eukaryotes are organisms made up of two basic types of cells. You may also hear them called prokaryotic and eukaryotic cells. Prokaryotes evolved first in Earth’s history around 3.8 billion years ago. These cells are smaller and simpler than eukaryotic cells.
Characteristics of Prokaryotes
Prokaryotes are always unicellular. That means the entire organism is only one cell. While a plasma membrane surrounds the cell, there are no membrane-bound organelles inside the cell. Inside the cell is a nucleoid, where double-stranded circular DNA is stored, cytoplasm, and ribosomes. Other simple organelles assist with movement and the replication of DNA. Prokaryotes also have flagella, or tails, that they use to move around their environment and a cell wall for protection.
Characteristics of Eukaryotes
Unlike prokaryotes, most eukaryotes are multicellular, but there are some unicellular eukaryotes. Their cells are also larger and more complex than prokaryotic cells. Eukaryotic cells have a plasma membrane. They also have membrane-bound organelles, including the nucleus, mitochondria, vesicles, vacuoles, Golgi apparatus, chloroplasts, and lysosomes. Like prokaryotes, they also have ribosomes to make proteins. Some eukaryotic cells have a cell wall. For example, plants have eukaryotic cells with cell walls. However, some don’t. Humans have eukaryotic cells without cell walls.
Eukaryotes come from Prokaryotes
Scientists believe eukaryotic cells evolved from prokaryotic cells around 2.7 billion years ago. One theory argues that one prokaryote ingested another prokaryote, but the prokaryote stayed living and producing energy. Over millions of years, the ingested prokaryote became the mitochondria that make energy in eukaryotic cells today.
The evidence for this theory is simple. Mitochondria have different DNA than the rest of the cell, and they make their own proteins.
Prokaryotes and Eukaryotes
Prokaryotes make up the bacteria and archaea kingdoms. Eukaryotes make up the animal, plant, fungi, and protista kingdoms. There are considerably more prokaryotes than eukaryotes on Earth. For example, you have about 37 trillion eukaryotic cells in your body, but scientists estimate you have three times that many bacteria living on and in you right now.
If you want to help your students learn about the differences and similarities between prokaryotes and eukaryotes, you will want to both teach them the information and allow them to work with it.
Sorting Eukaryotes and Prokaryotes
Sorting activities are great review activities because they provide students with all of the information they need and only require them to organize it. This will help them organize the information on prokaryotes and eukaryotes in their own brains. Plus, our brains love to sort. It feels calming to bring organization to chaos.
You can get my prokaryote and eukaryote sorting activity at Teachers Pay Teachers. I have both a printable and a digital version so that you can meet the needs of all of your students.
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