Every living organism on earth is made up of cells.
Some have only one cell, while others are multicellular.
Cells are incredible complex and they are considered to be the “building blocks” that make life.
Cells are self-sufficient, which means they can take care of themselves with all of the functions that they need to live and reproduce.
Different cells have different jobs, depending upon what they are needed for. The cells in our muscles help us move, while the cells in our nerve endings help us to feel things.
The world of cells is very fascinating because cells make up everything that is living; from the cells in your dog to the cells in the trees and even yourself.
Cells work together like little factories, to keep the organism functioning and healthy.
Cell Sizes
Not all cells are the same size or shape. Cells have a range of sizes and the largest one is the size of the “.”
period dot at the end of a sentence to the smallest cell that you need a high-powered microscope to see.
There are a few exceptions to this statement because science considers an egg yolk to be a cell, and it’s pretty big when you compare it to all of the others.
Cell Types
There are thousands and thousands of different cell types all over the earth.
Each living creature has cells that are unique, but overall we can divide cells up into two categories: eukaryotic cells, which have a nuclei and are bound by a membrane; and prokaryotic cells that have a nuclei and aren’t bound by a membrane.
Eukaryotic cells are divided into two other groups: animal cells and plant cells.
We are all considered to be part of the animal cell group, and things like the trees and flowers that you see are part of the plant cell group.
Inside the Cell
The parts of a cell are dependent upon its job.
Cells have organelles inside and each organelle has a specific function.
The word organelle simply means “small organ”, so you could think of organelles in the same way that you think of your own organs such as your lungs and heart.
Each organelle works together to keep the cell healthy. Organelles help in bringing food in and getting rid of waste as well as when the cell needs to repair itself and reproduce.
Organelles are like little miniature factories, all working together. If one organelle stops functioning, the entire cell and all other organelles will die.
Here are some of the main components that a majority of cells have:
- Membrane: Kind of like a skin that is on the outside of the cell. It allows some materials to come in and keeps other materials out.
- Mitochondria: This is the source of energy for a cell.
- Nucleus: This is called the cell’s “brains” and it contains all of the chromosomes that tell the rest of the cell the instructions that it needs to functions.
- Ribosomes: These are the little factories that make all of the different substances such as proteins that the cell requires to function.
- Lysosomes: This is the waste removal part of the cell. They get rid of all materials that are unwanted so that the cell stays healthy.
- Cytoplasm: This is the material that the cell is filled up with and other components float around in. It’s made mostly of water.
Facts about Cell Structure
- The Latin word “cellula” is the source of our word for “cell.” It translates into “small compartment.”
- Cells that are the same kind that are grouped together are called tissues and systems.
- The motor neurons are the longest cells in the human body and can be up to 4.5 feet long. They run from the big toe to your lower spinal cord.
- Different cells in the body live for different lengths of time. Some cells can live for weeks while other cells live only a few days.
- When some cells detect that they are sick or damaged, they will deliberately allow themselves to die so that the sickness or damage isn’t spread to the next generation of cells.
- 95% of the cells in our bodies are bacteria.
Interesting Facts about Biology
- In 30 seconds, the human brain can produce as much data and information as the Hubble Space Telescope produced in its entire lifetime.
- If you compared your brain storage capacity to computer storage, your brain would have over 4 terabytes of storage and could fit around 1 million songs.
- Our human bodies have 12 systems: the cardiovascular system, the digestive system, the endocrine system, the immune system, the integumentary system, the lymphatic system, the muscular system, the nervous system, the reproductive system, the respiratory system, the skeletal system, and the urinary system.
- Our bodies use our immune system involving microphages and antibodies to fight off a majority of infection.
- Each of our five senses has its own specialized receptors and sensory organs.
- Our five senses include a lot of things that we take for granted. These include: vision, hearing, smelling, tasting, touching, our balance, temperature, special awareness, and pain.
Cell Structure Quiz
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