Parts of a Cell | Learn about the parts of plant and animals cells

Parts of a Cell Cells are the basic units of life. Some organisms, like bacteria, are made from one cell, while others, like humans, are made up of trillions. Today, we are going to talk about the parts of a cell and the difference between plant cells and animal cells. Let's start off with some of the basics. The word cell is derived from the Latin word cellula, which means small room or compartment. Each cell is made up of different parts called organelles, each with its own specialized functions. Think of it this way. All of the organelles in a cell act a lot like the different parts of a castle, all with a specific role and function that help protect the key. One important thing to note, plant and animal cells are not exactly the same, which we will get to in a moment. First, let's discuss parts of a cell and what they do. The plasma membrane or cell membrane is on the outside of the cell. It is like a flexible wall that keeps all of the organelles safe inside the cell. Basically, the plasma membrane is like a castle wall with guards ready to defend its occupants. It determines what enters and exits the cell and protects it against invaders. Inside the cell, all of the organelles float around in a gel-like substance called cytoplasm. The cytoplasm is like the courtyard or inner grounds of a castle. This is where all of the important events take place and all the organelles interact with each other. The nucleus runs the cell, kind of like a brain. In our castle analogy, it is the castle's main stronghold or keep. It contains the cell's genetic blueprint or DNA. The nucleolus is inside the Ribosomes are the skilled craftspeople of the castle. They assemble proteins crucial to cell functions, just like artisans or builders create the tools and structures inside a castle. The endoplasmic reticulum or ER is a collection of tubes. Inside the tubes, proteins and fats are packed and transported. The rough ER works with the ribosomes and the smooth ER works with the Golgi apparatus and nucleus to help a cell function properly. Think of it like an intricate network of hallways and workshops running throughout a castle. The Golgi apparatus collects simple molecules together to make them more complex. It acts as the castle post office. It packages the complex molecules and stores them or sends them out of the cell. The Golgi apparatus also builds lysosomes. Lysosomes help rid a cell of waste materials, working a lot like our digestive system does. Consider them to be a castle's very efficient cleanup crew. Do you know what the powerhouses of a cell are? The mitochondria. Mitochondria act as a castle's forge. They make the energy necessary for a cell's operations, just like a castle forge produces heat and tools to support life within the castle. Then there are vacuoles, which serve as nutrient storage, just like a castle pantry. Now that we have outlined our basic cell models, let's talk about the differences between an animal cell and a plant cell. Plant cells have a rigid cell wall located just outside the plasma membrane. This causes them to look rectangular in shape. The cell wall helps plants stand upright without bones. It is like an extra strong castle wall. Plants also have chloroplasts, which convert water and sunlight into energy through photosynthesis. They are the castle garden. Plant cells only have one large vacuole. It stores water and sap inside and will grow or shrink depending on how much water a plant has stored. Here is an interesting fact. When a plant lacks water, its vacuole will shrink, which causes the plant to droop. Animal cells have some differences too. They have cilia or flagellum on the outside of the cell that helps them to move. Cilia look like tiny hairs and move together to propel the cell along, like small rapidly moving guards patrolling the castle walls. On the other hand, a flagellum is a single long projection that whips itself around to move the cell forward, similar to a few powerful guards patrolling a castle's outer borders. Animal cells can have either one, but not both. Now it's time for you to create your own cell model. Use a paper plate or piece of cardboard with colored pencils or markers to draw all of the organelles in a plant cell. Here's a reminder of all the parts. After you are done, check out our DIY plant cell model video to check your work. Thanks for learning with us. Hope you had fun learning with us. Visit us at learnbright.org for thousands of free resources and turnkey solutions for teachers and homeschoolers.