Cell Structure & Function Flashcards

This set of vocabulary flashcards covers cell history, the cell theory, different types of microscopes, and the various structures and organelles found in prokaryotic and eukaryotic cells.

Robert Hooke

Coined the term “cell” in 1667 after viewing thin sections of cork tissue under a magnifying glass.

Anton von Leeuwenhoek

Invented the first light microscope in the late 1600's and discovered “animalcules” (protists) in pond water.

Cell Theory

Developed from the mid 1700's to early 1900's stating: 1. All organisms are comprised of cells; 2. The cell is the basic unit of life; 3. All cells arise from preexisting ones.

Light Microscopes

Tools that use glass lenses and light with limited magnification ranging from $40\times$ to $1000\times$.

Electron Microscopes

Invented in the early 1900's, these use magnetic lenses and electron beams to reach magnifications greater than $300,000\times$.

TEM (Transmission Electron Microscope)

A type of microscope used specifically to view thin sections of individual cells.

SEM (Scanning Electron Microscope)

A type of microscope used specifically to view the external surface of individual cells.

Prokaryotic cell size

Typically ranges between $1-10\text{μm}$.

Eukaryotic cell size

Typically ranges between $10-100\text{μm}$.

Nucleoid region

The area in the cytoplasm of a prokaryotic cell where the unbound DNA sits.

Peptidoglycan

The material that composes the cell wall of prokaryotic cells for protection.

Pili (fimbriae)

Hair-like extensions attached to the capsule of prokaryotic cells used for attachment.

Envelope

A double membrane covering found on specific organelles like the nucleus, mitochondrion, and chloroplast.

Cell Wall

Provides shape and support; made of cellulose in algae and plants, or chitin in slime molds and fungi.

Cell (Plasma) Membrane

A phospholipid bilayer ($7.5-10\text{nm}$ thick) that regulates movement in and out of all cells.

Integral proteins

Components of the cell membrane used for transport.

Peripheral proteins

Components of the cell membrane used for receiving chemical signals.

Cholesterol

A component that holds the cell membrane together while promoting flexibility.

Nucleolus

A structure located inside the nucleus that produces ribosomes.

Cytoskeleton

A protein matrix running through the cytoplasm found in all cells.

Microtubules

Hollow tubes of the protein tubulin used for separating DNA during cell division.

Microfilaments

Thin strips of the protein actin used for moving substances through the cytoplasm.

Intermediate fibers

Rope-like fibers of the protein keratin that protect a cell against stress and trauma.

Microtrabeculae

A dense network of fine, wispy proteins that anchors cell structures in the cytoplasm.

Contractile vacuoles

Sacs found only in protozoans used to store and expel excess water.

Central vacuoles

Large sacs in plant cells used for water and starch storage, taking up $50-90\text{\%}$ of the cell's space.

Mitochondrion

The “powerhouse” of the cell where cellular respiration converts glucose into $ATP$.

Cristae

The folds of the inner membrane within a mitochondrion.

Chloroplast

The site of photosynthesis in plant and algal cells, converting light energy into glucose.

Stroma

The energy-rich fluid found inside the chloroplast.

Thylakoid disks

Membranous disks within the chloroplast covered by light-trapping pigments.

Granum

A stack of thylakoid disks.