Biology

• Cell Theory


  States all living organisms are composed of cells, the basic unit of life, and cells arise from preexisting cells.
• Magnification formula


  Calculation: image size divided by actual size, with units 1000 micrometres equaling 1 mm.
• Light microscope


  Instrument using light to magnify specimens, suitable for viewing living samples with lower resolution compared to electron microscopes.
• Electron microscope


  Instrument using electrons to magnify specimens, offering higher resolution and magnification but requiring more training and sample preparation.
• Sample staining


  Technique using stains like methylene blue to visualize colorless cell molecules, with fluorescent stains aiding in structure visualization. Also includes fluorescent anf immunofluorescent staining.
• Cryogenic


  Technique involving freezing protein solutions for electron microscopy, allowing 3D image creation at the moment of freezing for structural research.
• Freeze fracture


  Method to produce cell surface images by rapid freezing and fracturing, revealing 3D structures and insights into cell surfaces.
• Prokaryotic cell


  Simple structure, no nucleus or organelles, 70s ribosomes
• Eukaryotic cell


  Compartmentalised, larger, grouped into Protista, Plants, Fungi, Animals
• Nucleus


  Double membrane, contains genetic material, porous
• Rough ER


  Flattened sacs with attached ribosomes, synthesizes proteins
• Smooth ER


  Tubular membranes, synthesizes lipids, phospholipids, steroids
• Golgi Apparatus


  Stacked cisternae, processes and distributes polypeptides
• Mitochondria


  Double membrane, produces ATP by respiration
• Chloroplast


  Double membrane, produces organic compounds by photosynthesis
• Lysosome


  Single membrane, contains digestive enzymes
• Vacuoles


  Single membrane, store fluid, can digest or expel water
• Microtubules


  Move chromosomes, form points for other microtubules
• Cytoskeleton


  Protein fibers, maintain cell shape and help with movement
• Cilia


  Short, numerous, used for locomotion and creating currents
• Flagella


  Longer, fewer, used for locomotion
• Metabolism


  Chemical processes in living organisms to maintain life
• Excretion


  Process of eliminating waste products from the body
• Reproduction


  Process of producing offspring
• Homeostasis


  Maintenance of stable internal conditions in an organism
• Growth


  Process of increasing in physical size
• Nutrition


  Process of obtaining and using food for energy and growth
• Response to stimuli


  Reaction to external or internal changes in the environment
• Striated muscle cell


  Long, multinucleated, specialized for muscle contraction
• Aseptate fungal hyphae


  Long, multinucleated structures in fungi
• Red blood cells


  No nucleus, lifespan of ~120 days, involved in oxygen transport
• Phloem cell


  Breaks down organelles during development, adjacent cells maintain function
• Endosymbiotic theory


  Explains eukaryotic cell origin through engulfment of smaller cells
• Multicellularity


  Allows longer lifespans, larger and more complex organisms
• Paramecium


  Feeds by endocytosis, alters pH for enzyme activity
• Stem cells


  Undifferentiated cells with self-renewal potential
• Vesicles


  Fluid-filled sacs for material transport in and out of cells
• Striated


  Muscle fibers with visible stripes caused by differing tissue types.
• Cardiac


  Heart muscle tissue with atypical features like myofibrils and branched structure.
• Actin


  Protein component of muscle filaments.