Cellular Biology Exam Help — Cell Structure, Function & Division

Cellular biology covers cell structure, organelle functions, membrane transport, cell signaling, cell division (mitosis and meiosis), and molecular biology. NurseQuizPrep specialists provide cellular biology exam prep with clinical nursing correlations.

Cell Structure & Organelle Functions

Plasma membrane (phospholipid bilayer, fluid mosaic model), nucleus (DNA, gene expression), mitochondria (ATP production), endoplasmic reticulum (rough — protein synthesis; smooth — lipid synthesis), Golgi apparatus (protein packaging), lysosomes (intracellular digestion), ribosomes (protein synthesis), cytoskeleton (structure and transport).

• Mitochondria: site of cellular respiration — produces ATP via ETC
• Ribosome: site of protein synthesis — 70S (prokaryote) vs 80S (eukaryote)
• Lysosomes: contain hydrolytic enzymes — digest cellular debris and pathogens

Membrane Transport & Cell Signaling

Passive transport (diffusion, facilitated diffusion, osmosis) vs. active transport (Na+/K+ ATPase pump), endocytosis and exocytosis, receptor-mediated signaling, and second messenger systems.

• Osmosis: water moves toward higher solute concentration
• Na+/K+ ATPase: 3 Na+ out, 2 K+ in per cycle — maintains membrane potential
• cAMP second messenger: activated by beta-agonists (e.g., albuterol → bronchodilation)

Cell Division: Mitosis & Meiosis

Phases of mitosis (PMAT: Prophase, Metaphase, Anaphase, Telophase) and meiosis (two division rounds). Cancer as a disease of cell cycle dysregulation. Apoptosis vs. necrosis.

• Mitosis: produces 2 identical diploid cells — somatic cell division
• Meiosis: produces 4 genetically unique haploid gametes — sex cell production
• Cancer: proto-oncogene → oncogene mutation; tumor suppressor gene loss (p53)