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CCT: Cell Organelles Lesson

Cell Organelles

Organelles are specialized structures that perform a specific job within the cell. Watch the video below for an overview of the organelles discussed in this lesson.

Cell Organelles

Cell organelles vary in size and have a structure that best enables them to perform their tasks.

Select each keyword below to learn about cell structure.

We Have a Special Relationship!

relationship image between chloroplasts and mitochondria

There is a special relationship between mitochondria and chloroplast.

Both have the following:

  1. have circular DNA similar in size and genetic code to bacteria
  2. reproduce in a manner similar to bacteria; if they are removed from the cell, the cell cannot generate more of these organelles
  3. contain their own ribosomes similar to bacteria

The Endosymbiotic Theory

Take a look at the picture that illustrates this.

Endosymbiotic Theory, description of diagram below

 

See description of diagram Links to an external site.

Lynn Margulis in 1967 proposed that these organelles arose as part of a cooperation between a larger cell and either a cyanobacterium (in the case of chloroplasts) or another free-living bacterium (in the case of mitochondria). Scientists think that the larger cell engulfed the bacterium, providing it with nutrients and shelter, and the bacterium either provided photosynthesis and/or cellular respiration to the larger cell.

 

Cell Organelles Challenge and Before You Go

Practice Time! Use the knowledge you learned from the lesson to complete the practice activities below.

 

The following key points are from the explore section of the lesson. You must know the following information before moving to the next lesson. This is just a summary of the key points.

 

  1. What are some examples of organelles?
    • Nucleus, endoplasmic reticulum, golgi body, ribosome, cell wall, mitochondria, and chloroplast
  2. What are three organelles found in plant cells, but not in most animal cells?
    • Chloroplast, cell wall, and vacuole
  3. What is the Endosymbiotic Theory?
    • Proposed by Lynn Margulis that states that organelles evolved from a relationship between a larger cell and either a chloroplast or mitochondria

IMAGES CREATED BY GAVS (FREEPIK)