Tiny, single-celled organisms that are considered one of the three main domains of life, along with bacteria and eukaryotes. Many of these are known as extremophiles because they thrive in extreme environments like hot springs or salty water.

Extremely tiny, single-celled living things that can be found everywhere. They are so small that you need a microscope to see them. Most of these are helpful, playing roles in digestion, soil formation, and medicine production. However, some can cause infections and diseases.

A thin, flexible layer that surrounds all cells, separating the inside of the cell from its environment. It's like a gatekeeper, controlling what goes in and out of the cell, and is made of a lipid bilayer, which is semi-permeable.

A fundamental structure in cell membranes, forming a barrier that separates the cell's interior from its external environment.

These are like the fats and oils in our food, but they're also found in our bodies. They're important for storing energy, building cell parts, and helping with other important jobs. Think of them as the waxy, oily, or fatty substances that help our bodies work.

A rigid outer layer that provides support and protection to plant, bacterial, fungal, and some algal cells.

The jelly-like substance inside a cell that holds all the cell's parts (organelles) in place and helps them function.

Short for deoxyribonucleic acid, is like a set of instructions that tells your body how to grow and work.

A type of cell that has a nucleus, a central compartment where its DNA is stored. Think of it like a room in a house where important papers (the DNA) are kept safe and organized. All plants, animals, and fungi are made of these types of cells.

A tiny building block that makes up fungi, a group of living things that includes mushrooms and molds.

A set of instructions that tells a living thing how to grow and develop. It's found inside every cell and carries information that determines traits like eye color or whether an animal is a dog or a cat. The main type of this material is called DNA, which stands for deoxyribonucleic acid. Fill in the blank: ________

Tiny organs inside a cell, each with its own membrane that separates it from the rest of the cell's contents. Fill in the blank: ________

An organism is made up of many cells, unlike single-celled organisms. Fill in the blank: ________

The cell's control center. It's a membrane-bound organelle that contains the cell's genetic material, which is DNA, and it directs many of the cell's activities. What is it?

A tiny building block of a plant; eukaryotic cell, meaning it has a nucleus inside a membrane. These cells have a few extra parts compared to animal cells, including a rigid outer layer called a cell wall, a large storage space called a vacuole, and special parts called chloroplasts where photosynthesis happens. Fill in the blank: ________

The word means “before nucleus.” These are called this because they don't have a nucleus or other membrane-bound organelles. Fill in the blank: ________

A tiny living thing, a eukaryote, that's not an animal, plant, or fungus. Fill in the blank: ________

Tiny cell parts that act like protein factories within cells. Fill in the blank: ________

Of organisms, such as protozoans and certain algae, consisting of a single cell. Fill in the blank: ________

Fission (splitting) into two organisms approximately equal in size. Fill in the blank: ________

An animal or plant, especially one that is so small that you cannot see it without using a microscope. Fill in the blank: ________

A thin, flexible layer that acts as a boundary, separating different spaces or compartments within a cell or organism.