---
title: "Protists: The Eukaryotes That Are Not Plants, Animals or Fungi"
description: "Most eukaryotic diversity sits outside the three familiar kingdoms, in lineages that photosynthesise, hunt, or do both depending on the light. Their organelles record a history of one cell taking up a"
canonical: https://lightmysky.com/learn/science/protists-the-eukaryotes-that-are-not-plants-animals-or-fungi-mt_CHb8H727nW
source: https://lightmysky.com/learn/science/protists-the-eukaryotes-that-are-not-plants-animals-or-fungi-mt_CHb8H727nW.md
retrieved: 2026-09-12
---

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# Protists: The Eukaryotes That Are Not Plants, Animals or Fungi

Most eukaryotic diversity sits outside the three familiar kingdoms, in lineages that photosynthesise, hunt, or do both depending on the light. Their organelles record a history of one cell taking up another, which is why they are the evidence for endosymbiosis rather than an afterthought to it.

Subject: Science · Area: Organisms & Life Processes · Ages 18 to 19
Page: https://lightmysky.com/learn/science/protists-the-eukaryotes-that-are-not-plants-animals-or-fungi-mt_CHb8H727nW

## Ready when they can

- Explain the endosymbiotic origin of mitochondria and plastids and state the evidence for each
- Describe two contrasting protist lifestyles and the cell structures each depends on
- Say why the word protist describes a grade of organisation rather than a natural group

## Lesson: The eukaryotes outside the big three

All life sorts into Archaea, Bacteria, and Eukarya, and eukaryotes arose about 2 billion years ago. One cell swallowed another and kept it as the mitochondrion, and later some cells swallowed sunlight users that became chloroplasts.

Both partners still betray their past: they carry their own DNA, wear two membranes, and divide on their own like free bacteria. All eukaryotes keep mitochondria or their traces, while only some lines keep plastids, which is why mitochondria joined first.

**Example.** Some protists hunt and engulf food, others trap sunlight with chloroplasts, and some switch with the light. Hunters lean on gear that catches food, while sunlight users lean on their captured chloroplasts.

**Tip.** Protist names a level of organisation, not one family, since its members branch from many points of the tree. Never treat it as a single branch.

**Recap.** Swallowed cells became powerhouses and plastids, and protists show that mixed history across many branches.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Single-Celled Organisms](https://lightmysky.com/learn/science/single-celled-organisms-mt_g9RcQOhU5d)
- [Prokaryotic and Eukaryotic Cells](https://lightmysky.com/learn/science/prokaryotic-and-eukaryotic-cells-mt_vlL4GinuH6)

## Opens up

- [Fungi: Hyphae, Spores and Digestion Outside the Body](https://lightmysky.com/learn/science/fungi-hyphae-spores-and-digestion-outside-the-body-mt_qfp2nuk1IH)