Components of human cells

What is plasma membrane and its function?

A flexible, protective barrier made of a phospholipid bilayer and proteins.

Regulates what enters/exits the cell to maintain a stable internal environment. Essential to the life of the cell

What is cytoplasm and its function?

A gel-like, water-based fluid that fills the inside of the cell.

Supports and suspends the cell's organelles and provides the necessary medium for vital chemical reactions to occur.

What is the nucleus and its function?

A large, spherical body located near the center of the cell that houses the genetic material (DNA).

Acts as the cell’s "control center" by regulating cellular activities and storing the instructions needed for the cell to function, grow, and reproduce.

What is the nuclear membrane and its function?

A double-layered, porous membrane that surrounds the nucleus.

Protects the nucleus, allowing in only specific

materials

What is the nucleolus and its function?

A dark, dense, membrane-free structure located inside the nucleus; cells typically contain one to four.

Responsible for producing RNA and ribosomes.

What is mitochondria and its function?

Elongated, rod shaped structures that contain their own DNA; known as the “power plant” of the cell

It converts nutrients into energy, producing adenosine triphosphate (ATP) to power cellular processes.

What are ribosomes and their function?

Small, dense granules made of RNA found either floating in the cytoplasm or attached to the endoplasmic reticulum.

The site of protein synthesis, creating proteins for both internal use within the cell and for export outside the cell.

What is cilia and its function?

Short, hair-like projections extending from the cell membrane, made of microtubules.

Aid in the movement of substances or fluids across the surface of the cell.

What is flagella and its function?

Long, hair-like projections extending from the cell membrane, made of microtubules.

Provide movement for the entire cell using a whip-like, propeller motion.

What is endoplasmic reticulum and its function?

A complex network of interconnected, fluid-filled sacs and channels that links the cell membrane to the nuclear membrane. It exists in two forms: Rough ER (RER), which has ribosomes attached, and Smooth ER (SER), which does not.

Serves as a transport system for materials throughout the cell.

• RER: Synthesizes and transports proteins.

• SER: Synthesizes lipids, including steroids.

What is the golgi apparatus and its function?

A stack of four to six flattened, fluid-filled membranous sacs typically found near the nucleus and connected to the endoplasmic reticulum.

Known as the “packaging and shipping plant” of the cell; it modifies, packages, and secretes materials for external use and forms lysosomes for use within the cell.

What are lysosomes and what is their function?

Membrane-bound sacs created by the Golgi apparatus.

The cell’s "recycling center"; they contain digestive enzymes that break down waste materials, damaged cell components, and foreign substances entering the cell.

What is the cytoskeleton and what is the function?

Made of of protein microfilaments and microtubules.

Acts as the cell’s "skeleton," maintaining the cell's shape and structure. It also anchors organelles in place and provides a transport system to move them throughout the cell.

What are centrioles and their function?

A pair of rod-shaped structures made of microtubules, located near the nucleus.

Participate in cell reproduction through the distribution of DNA to new cells