Bacterial Structure

Contributor: Felicia Sabur. Lesson ID: 11647

Did you know you have peptidoglycan and phospholipid-lipopolysaccharide on your body? They are part of the bacteria that you harbor! Learn more about the makeup of these tiny but complex creatures!


Life Science

learning style
Kinesthetic, Visual
personality style
Grade Level
High School (9-12)
Lesson Type
Dig Deeper

Lesson Plan - Get It!

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Bacteria seem like such tiny, simple creatures. However, they are like tiny mobile cities that can bring down the strongest among us!

There are many parts that make up a bacterium cell.

In this lesson, you will learn about nine of their parts. Write all of your vocabulary words in the Lesson 7 Vocabulary section of your Viruses and Bacteria Unit Workbook. If you didn't print out this resource in Lesson One, please download and print it from Downloadable Resources in the right-hand sidebar.

Before moving on, if you missed, or need to review, the previous six lessons in this Viruses and Bacteria series, find them under Related Lessons in the right-hand sidebar.

Bacteria cells are a type of prokaryote cell. A prokaryote is a unicellular organism that is missing a distinct nucleus with a membrane. They have a nucleoid, but there is no membrane that surrounds the DNA material.

  • The nucleoid (meaning nucleus-like) is an irregularly-shaped area within the cell of a prokaryote that contains the genetic material.
  • Ribosomes are the protein builders, or the protein synthesizers, of the cell. They connect one amino acid at a time to build long chains of amino acids.
  • Plasmid is a small, circular, double-stranded DNA molecule that is separate from a cell's nucleoid and it can replicate itself independently of it.
  • Cytoplasm is the thick jelly-like fluid that fills a cell.
  • The plasma membrane is a double layer of lipids and proteins that forms the boundary of the cytoplasm of a cell and regulates the passage of molecules in and out of the cytoplasm.
  • The cell wall is the ridged outermost layer of the cell.
  • The capsule is found in some bacterial cells and is an additional layer of protection.
  • Flagellum is a tail-like structure that is used for mobility.
  • The pili are hair-like structures on the cell wall that allow the bacteria to adhere to other substances or bacteria.

The picture below show a bacterium with all of its parts labeled:

average prokaryote cell

Image by Mariana Ruiz Villarreal, via Wikimedia Commons, has been released into the public domain.

The following video covers the different parts of the bacterial cell. Fill out and label parts of the cell on the blank cell picture as you watch the video for Lesson Seven in your Viruses and Bacteria Unit Workbook.

bacteria cell video by ColleyBiology:

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Discuss with your teacher or parent which part of the cell allows bacteria to group themselves together.

The pili are very important because they allow bacteria to adhere themselves together in various formations. These formations are very helpful to doctors and researchers when they are trying to identify a bacterium.

  • Can you list the three main shapes and organizations by groups from the previous Related Lesson on bacterial classification?

In the Got It? section, you will be making a 3D model of a bacterium. You will also put together a short lesson and teach your parent or teacher about all nine parts of a bacterium.

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