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Last updated: 11th May 2023

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Eukaryota

Keywords

Eukaryote, Eukaryota, multi-celled organism, nucleus, common ancestor, chimeric protobacterium.

Introduction

Eukaryota are multi-celled organisms. Anything that is a living organism that is more than one cell in size is considered a eukaryote. So this means that a plant is a eukaryote. A sheep is a eukaryote. A fish is a eukaryote. You are a eukaryote.

What's the Difference?

The eukaryote has a different makeup to the likes of bacteria and archaea, in the fact that each cell in the organism has a nucleus in them. So, your DNA has a nucleus which holds your genetic information. This is because you are a eukaryote. That being said, bacteria and archaea both hold DNA, but do it in a different way.

All eukaryotes carry a common ancestor. If you track far enough back in time - we're talking thousands of years ago - then you'll find that you all share a similar ancestor.

Here is a YouTube video from Sci-ology on the Eukaryotic Cell:

Interesting fact: the human genome shares 50% genetic information with a banana. It is mainly the proteins, rather than the DNA though.

How Eukaryotes Reproduce

Typically, a eukaryote can replicate the same as a bacteria or archaea does. But it is usually by a different process. For example, the cells in our body replicate by a process called mitosis. This is where there is a single that duplicates everything within it, and through a process called cytokinesis then splits in half with the organelles inside. Other processes include meiosis, which happens sometimes in eukaryotes, but only for a few specific cell types. This is mainly how bacteria reproduce, as it clones the cell.

Origin Story

No, this isn't like the origin story for Wolverine or anything like it, but eukaryotes do originate from a source of chimeric protobacterium. So in essence, although eukaryotes have multiple cells, and carry organelles within them, they were first bacterium.

The first known sign of eukaryotic organisms happened around 2 billion years ago. So, while the dinosaurs were around 65 million years ago, these fossils show that it was about 1.5 billion years ago that they existed.


Too Long; Didn't Read

Eukaryota are multi-cell organisms that include animals, plants and humans. The makeup of a eukaryote is similar, but different to bacteria, in that there are more than one cell in an organism, they have different organelles in each cell to a bacteria, and other factors include that they take longer to reproduce new cells. Eukaryota have evolved from protobacterium, an ancient form of bacteria.

Suitability

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Related Pages

Domains iconArchaea

Domains iconBacteria

Famous Scientists iconCarl Woese

DNA iconHuman Cells

Resources

These are the following resources that I recommend to use. You don't have to use them, but I have found them to be useful when presenting this lesson.

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