Biology Chapter 4 - A Tour of the Cell Flashcards

Light Microscope: Utilizes visible light passing through specimens to magnify images of microorganisms and thin tissue slices.
Cell Theory: Asserts all living organisms are made of cells; all cells arise from existing cells.
Electron Microscope: Employs a focused beam of electrons, achieving resolutions that can identify structures as small as 2 nanometers.
Scanning Electron Microscope: Examines surface structures in detail, providing 3D-like images of cell surfaces.
Transmission Electron Microscope: Analyzes internal cellular structures through thin sections of specimens.

Plasma Membrane: A protective barrier surrounding all cells, regulating entry and exit of substances.
Chromosomes: Structures that contain genes composed of DNA, essential for genetic information.
Ribosomes: Molecular machines that synthesize proteins from messenger RNA.
Cytoplasm: The viscous fluid inside cells, where biochemical processes take place.
Nucleoid: Region in prokaryotic cells where DNA is localized and coiled.

Flagella: Whip-like structures that facilitate cellular movement.
Nucleus and Organelles: Grouped into functional categories for cellular manufacturing, breakdown of molecules, energy processing, and structural support.
Endoplasmic Reticulum (ER): Comprises two types; rough ER has ribosomes, while smooth ER does not, involved in various cell functions.

Mitochondria: The powerhouse of eukaryotic cells, converting food into ATP through cellular respiration.
ATP: The primary energy carrier in cells, fueling cellular activities.
Chloroplasts: Organelles in photosynthetic organisms, responsible for photosynthesis and energy capture.

Cytoskeleton: A network of protein fibers providing cell shape and support; includes microfilaments, intermediate filaments, and microtubules.
Microfilaments: Composed of actin, they support cell structure and stabilize the membrane.
Intermediate Filaments: Various proteins that anchor organelles and maintain cell integrity.
Microtubules: Hollow tubes controlling cell shape and playing vital roles in transport and division.

Extracellular Matrix (ECM): A network outside the cell that supports tissue structure and facilitates cell communication through glycoproteins.
Integrins: Membrane proteins connecting the ECM with the cytoskeleton, facilitating signaling.
Cell Junctions: Types include tight junctions (prevent leakage), anchoring junctions (hold cells together), and gap junctions (allow intercellular communication).

Cell Wall: A rigid structure made primarily of cellulose, distinguishing plant cells from animal cells and limiting rapid expansion.
Central Vacuole: Functions similarly to lysosomes but is larger in plant cells, storing nutrients and waste products.

Endosymbiosis: A biological phenomenon where two organisms live in close proximity to mutual benefit.
Plasmodesmata: Channels in plant cell walls allowing intercellular communication, analogous to gap junctions in animals.
Metazoan: A term for multicellular organisms representing complex biological systems with specialized functions.