Cell Structure and Function: Microscopes, Prokaryotes, and Eukaryotes

A vocabulary-style flashcard deck reviewing cell structure, microscopy, prokaryotic features, and eukaryotic organelle functions.

Magnification

The increase in a cell's displayed size compared to its actual size.

Resolution

The measure of clarity of an image, defined as the ability to show two nearby objects as separate.

Scanning Electron Microscope (SEM)

A microscope that uses electrons scanning across the surface of a cell to visualize the texture and exterior shape of the cell.

Transmission Electron Microscope (TEM)

A microscope that passes electrons through a thin slice of a cell to show internal cellular details, such as organelles.

Cell Theory

A foundational biological theory established between the 1660s and mid-1800s stating that all living things are composed of cells and all cells come from other cells.

Surface-to-Volume Ratio

The ratio comparing a cell's outer membrane area to its internal volume; smaller cells have a larger surface-to-volume ratio, facilitating efficient exchange of materials.

Plasma Membrane

A selectively permeable phospholipid bilayer with embedded channel and membrane proteins that regulates the movement of substances into and out of the cell.

Prokaryotic Cells

Small, simple cells belonging to domains Bacteria and Archaea that lack a nucleus and membrane-bound organelles.

Nucleoid

The specific region within a prokaryotic cell where its DNA is located.

Prokaryotic Cell Wall

A protective, rigid structure outside the plasma membrane of prokaryotes that maintains cell shape and can be targeted by antibiotics such as penicillin.

Capsule

A jelly-like outer coating surrounding certain prokaryotic cells that helps the cell stick to surfaces.

Flagella

Long surface projections that help propel a prokaryotic or eukaryotic cell through its environment.

Fimbriae

Short attachment structures on the surface of prokaryotes that help the cell attach to other surfaces.

Eukaryotic Organelle Functional Groups

The 4 basic functional categories of eukaryotic organelles: genetic control (nucleus, ribosomes), manufacturing/distribution/breakdown (ER, Golgi, lysosomes, vacuoles, peroxisomes), energy processing (mitochondria, chloroplasts), and structural support/movement/communication (cytoskeleton, plasma membrane, cell wall).

Nucleus

The eukaryotic organelle that houses cellular DNA and contains genetic instructions for the cell.

Nuclear Envelope

A double phospholipid bilayer (inner and outer membrane) perforated with protein pores that encloses the nucleus and regulates transport.

Nuclear Localization Signal (NLS)

A molecular tag or ticket required for large, complex molecules (such as mRNA, ribosome subunits, and polymerases) to pass through nuclear pores.

Nucleolus

A dense region inside the nucleus where ribosomal RNA (rRNA) is synthesized and ribosome subunits are assembled.

Ribosome

A cellular structure composed of rRNA and proteins that carries out protein synthesis.

Free Ribosomes

Ribosomes suspended in the cytoplasm that manufacture proteins meant to function within the cytosol.

Bound Ribosomes

Ribosomes attached to the exterior of the endoplasmic reticulum that manufacture proteins designed to be inserted into membranes or exported from the cell.