Cell Structure, Function, and Properties

Vocabulary flashcards covering fundamental terms related to cell structures, their functions, properties, and representative bacteria.

Cell

Fundamental structural and functional unit of all living organisms.

Genetic Information (DNA)

Hereditary material that can be replicated and passed to the next generation.

Anabolism

Metabolic pathway that builds complex molecules and stores energy.

Catabolism

Metabolic pathway that breaks down molecules and releases energy.

Prokaryotic Cell

Unicellular organism lacking a nucleus and membrane-bound organelles.

Peptidoglycan

Polymer forming the bacterial cell wall that provides shape and protection.

Capsule

Polysaccharide layer outside some bacteria that offers extra protection.

Flagella

Long protein filaments (flagellin) enabling bacterial motility.

Pili

Short protein appendages (pilin) used for attachment and DNA transfer.

Binary Fission

Asexual reproduction where a prokaryote divides into two identical cells.

Gram-Positive Bacteria

Bacteria with a thick peptidoglycan wall that stain purple with crystal violet.

Gram-Negative Bacteria

Bacteria with a thin peptidoglycan wall and outer LPS layer that stain pink/red.

Lipopolysaccharide (LPS)

Molecule forming the outer membrane of Gram-negative bacteria, contributing to pathogenicity.

Crystal Violet Retention

Ability of Gram-positive bacteria to keep the primary stain, turning them purple.

Staphylococcus aureus

Gram-positive bacterium causing skin infections and food poisoning.

Streptococcus pneumoniae

Gram-positive bacterium responsible for pneumonia and sinusitis.

Escherichia coli (E. coli)

Gram-negative bacterium common in UTIs and food poisoning.

Salmonella enterica

Gram-negative bacterium causing typhoid fever and foodborne illness.

Eukaryotic Cell

Cell containing a nucleus and membrane-bound organelles.

Cell/Plasma Membrane

Phospholipid bilayer controlling substance entry, exit, and signaling.

Cytoplasm

Semi-fluid cytosol where metabolic reactions and organelle support occur.

Cytoskeleton

Network of protein filaments providing shape, transport, and movement.

Microtubules

Largest cytoskeletal filaments of tubulin that guide organelle movement and form spindle fibers.

Intermediate Filaments

Durable fibers providing mechanical strength and organelle stabilization.

Microfilaments

Actin rods involved in cell cortex support, cytokinesis, and muscle contraction.

Nucleus

Double-membrane organelle storing DNA and regulating gene expression.

Nuclear Envelope

Double membrane surrounding the nucleus, pierced by selective pores.

Nucleolus

Dense nuclear region where ribosomal RNA and subunits are produced.

Rough Endoplasmic Reticulum

ER studded with ribosomes; synthesizes, folds, and transports proteins.

Smooth Endoplasmic Reticulum

ER lacking ribosomes; synthesizes lipids, steroids, and detoxifies toxins.

Golgi Body

Stack of cisternae that modifies, sorts, and packages proteins and lipids.

Ribosome

rRNA-protein complex translating mRNA into polypeptides.

Mitochondrion

Double-membrane organelle generating ATP and regulating apoptosis.

Cristae

Infoldings of the mitochondrial inner membrane increasing surface area for ATP production.

Cellulose Cell Wall

Rigid plant structure providing support and protection outside the plasma membrane.

Chloroplast

Plant organelle where photosynthesis occurs, containing chlorophyll, DNA, and ribosomes.

Plasmodesmata

Microscopic channels allowing cytoplasmic exchange between adjacent plant cells.

Large Central Vacuole

Plant sac storing materials and maintaining turgor pressure; surrounded by tonoplast.

Tonoplast

Membrane enveloping the large central vacuole in plant cells.

Centriole

Paired cylindrical structures organizing the mitotic spindle and microtubules.

Lysosome

Enzyme-filled vesicle that digests macromolecules, debris, and pathogens.

Small Temporary Vacuole

Short-lived animal-cell vesicle for storage, transport, and osmotic balance.

Mitosis

Asexual eukaryotic division producing two genetically identical daughter cells.

Meiosis

Eukaryotic division forming four genetically diverse gametes for sexual reproduction.