Cells are too small to be seen without major magnification. To see the organelles, you need to magnify further.

All living things are made up of a bunch of cells. What is pretty each, when it comes to humans, is that there are more bacterial cells in or on you than there you have actual human forms. Each cell is made up of much smaller units that each perform a different job. These smaller parts are called organelles. Organelles can be thought of as organs of the cells they are in. Each organelle is vital to complete all the tasks for the body itself. Each cell is surrounded by a protective shield that is made from protein and lipids (fats) called the plasma membrane. This membrane decides what can go into and come out of the cell itself. There is a control center of the cell called a nucleus that has all the instructions for carrying out every activity within the entire unit.

This is a small compact organelle called the mitochondria that helps the cell make usable energy from food. Everything in the cell is covered in a jelly-like substance called cytoplasm this helps things move around and be used by other parts. The body of the cell is held up by an organelle called endoplasmic reticulum and it allows things to be transported to neighboring cells. These worksheets will help you learn more about all the organelles. We start by exploring the main structures that function to keep the basic units of life thriving. The investigate how they interact and the movement of substances within the plasma membrane. We identify features that are distinct to both plant and animal forms of these structures. We also look at the history behind how we learned all of this.

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Printable Cell Organelles Worksheets

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What Are They?

Organelles are tiny structures inside the cells of organisms. In the same way that each organ in the body does a specific job, each organelle has its own distinct way of contributing to the overall health of the unit.

What Are They? Questions

The cells of plants and animals also have organelles that are specific to them, because each for needs to perform some very different kinds of functions. When you make your own food, you need some more ingredients for your recipe.

The Main Parts

A nucleus functions like a "brain," directing the actions of all the other organelles. Most cells only have one nucleus.

QUESTIONS: The Main Parts

The endoplasmic reticulum is a core organelle that plays a role in producing, processing, and transporting proteins and lipids.

Specialized Organelles

Chloroplasts contain a green pigment called chlorophyll. In the first step of photosynthesis, the chloroplasts capture sunlight when molecules of chlorophyll absorb energy.

QUESTIONS: Specialized Organelles

Storage granules are another kind of specialized organelle in cells that produce a lot of material that needs to be released from the cell.

The Nucleus

The most important function that the nucleus performs is to store deoxyribonucleic acid, more commonly known as DNA.

QUESTIONS: The Nucleus

What is the name of the process when the nucleus makes RNA?


The number of mitochondria in a cell vary, depending on what kind of cell it is. Simple bodies require less energy and contain only one or two mitochondria.

QUESTIONS: Mitochondria

The structure of mitochondria is as follows. The organelle is protected by a smooth outer membrane. The shape of this membrane varies.


The ribosome is made up of two main parts (subunits) that join together in order for the ribosome to make a new protein.

QUESTIONS: Ribosomes

Messages containing these specific instructions are transmitted to the cell by messenger RNA.

Endoplasmic Reticulum

The ER is a continuous membrane system, and the space within the ER is called the lumen. The ER extends from the cell membrane through the cytoplasm and is continually connected to the nuclear envelope.

QUESTIONS: Endoplasmic Reticulum

The smooth endoplasmic reticulum is a transitional area for transport vesicles and plays a role in the creation of carbohydrates and lipids.


Only plants and photosynthetic organisms contain chloroplasts.

QUESTIONS: Chloroplasts

While chloroplasts are generally oval-shaped, their shape can vary. They vary in size as well, sometimes taking up most of the space inside of a cell.

The Discovery

Scientists have been aware of the existence of organelles as far back as the 1600s.

QUESTIONS: The Discovery

But it wasn't until the invention of the transmission electron microscope in 1933 that scientists were able to observe and study cells more closely.


Vacuoles are fluid-filled sacs separated from the cytoplasm by a single membrane called the tonoplast.


Vacuoles are also used by the cell for storage. They keep important minerals, water, nutrients, ions, waste products, smaller molecules, enzymes, and plant pigments separate from the cytoplasm.