General Biology 1 Study Guide: Cell Theory, Cell Types, Organelles, and Plant Tissues

Vocabulary flashcards covering key terms from the notes on cell theory, cell types, organelles, and plant tissues.

Cell theory

Unified concept that all living things are composed of one or more cells, the cell is the basic unit of life, and new cells arise from existing cells.

Omnis cellula e cellula

Rudolf Virchow's assertion that all cells arise from pre-existing cells.

Prokaryotic cell

A cell lacking a nucleus or other membrane-bound organelles; DNA is in the nucleoid; usually unicellular; examples include Streptococcus and Escherichia coli.

Eukaryotic cell

A cell with a nucleus and membrane-bound organelles; includes protists, fungi, plants, and animals; can be unicellular or multicellular.

Nucleus

Control center of the cell that houses and protects the cell's DNA.

Nucleolus

Region inside the nucleus where ribosomes are assembled.

Ribosome

Organelle that synthesizes proteins by translating mRNA; may be free-floating or attached to rough ER.

Cytoplasm

Gel-like interior of the cell that holds organelles and is the site of many metabolic activities.

Cell membrane

Phospholipid bilayer that regulates the movement of substances into and out of the cell.

Rough Endoplasmic Reticulum

Rough ER with ribosomes; synthesizes and transports proteins.

Smooth Endoplasmic Reticulum

Smooth ER lacking ribosomes; synthesizes lipids and aids in transport of materials.

Golgi apparatus

Stack of membranes that processes, modifies, and packages proteins and lipids from the ER for secretion or delivery.

Mitochondrion

Organelle that generates ATP through cellular respiration; powerhouse of the cell.

Chloroplast

Organelle that carries out photosynthesis, converting light energy into chemical energy (glucose).

Lysosome

Organelle containing digestive enzymes that break down waste materials and old organelles.

Vacuole

Membrane-bound storage sac; large in plant cells; stores water, nutrients, and waste.

Nucleoid

Region in prokaryotic cells where DNA is located; not enclosed by a membrane.

Extremophile

Prokaryotes adapted to extreme environments; include halophiles, thermophiles, psychrophiles, and acidophiles.

Endomembrane system

Network of membranes (ER, Golgi, vesicles) involved in synthesis, modification, and transport of proteins and lipids.

Protist

Eukaryotic, often single-celled organisms; may be photosynthetic or heterotrophic; not plants, animals, or fungi.

Fungi

Eukaryotic decomposers; can be unicellular (yeast) or multicellular; heterotrophic.

Xylem

Complex permanent tissue that transports water and minerals; composed of vessels and tracheids.

Phloem

Complex permanent tissue that transports sugars and other metabolic products; includes sieve elements and companion cells.

Parenchyma

Simple permanent plant tissue with living cells; involved in photosynthesis, storage, and tissue repair.

Collenchyma

Simple permanent tissue with thickened but flexible cell walls providing support.

Sclerenchyma

Simple permanent tissue with thick, lignified walls providing rigid support; often dead at maturity.

Apical meristem

Primary growth region at the tips of shoots and roots; enables lengthwise growth.

Lateral meristem

Secondary growth region that thickens stems and roots; includes vascular cambium and cork cambium.

Vascular cambium

Lateral meristem that produces secondary xylem and phloem, increasing girth.

Cork cambium

Lateral meristem that produces cork and contributes to bark.

Meristem

Plant tissue consisting of actively dividing cells that enable growth.

Mitosis

Process of cell division that produces two genetically identical daughter cells; essential for growth and tissue repair.

Homeostasis

Maintenance of stable internal conditions in an organism.

Metabolism

All chemical reactions in a cell that provide energy and building blocks for growth.