Gen bio.

• Types of cells


  • Prokaryotic Cells
  • Eukaryotic Cells
• Monera-archae bacteria are old (origin of life)
• Eukaryotic Cells


  • Animals
  • Plants
  • Fungi
  • Protists
• Rate of cell division for somatic cells is 0.5-1.5 hours for males and 74 hours for females during gestation-late fetal age
• Protein production is between 0.02 and 0.13% per hour in vivo in humans
• Transport of materials occurs through organelles and membrane
• Prokaryotic Cell


  • Plasma membrane
  • Cytoplasm
  • DNA
  • Nucleoid region
  • Ribosomes
• Types of Archaebacteria


  • Halophiles
  • Methanogens
  • Thermophiles
• Bacteria Shapes


  • Rods (Bacilli)
  • Spheres (Cocci)
  • Spirals
• Cell processes include reproduction, rate of cell division, protein production, and transport of materials
• Prokaryotic Cell Features


  • Cell Size: 1μm to about 5μm
  • Genetic Materials: Circular DNA
  • Ribosomes: 30S and 50S subunits form 70S sediments
  • Membrane-bounded organelles: not present
  • Reproduction: conjugation and budding
  • Rate of cell division: 4-20 minutes
  • Protein production: e.coli growing in rich medium, around 20 minutes acids per second per ribosome
  • Transport of materials: translocons/diffusion
• Eukaryotic Cell Features


  • Cell Size: 10μm to about 100μm
  • Genetic Materials: Chromosomes linear structure
  • Ribosomes: 40S and 60S subunits form 80S sediments
  • Membrane-bounded organelles: present
  • Reproduction: mitosis, meiosis
• We have to follow the doctor's prescription when taking antibiotics because the bacteria can immediately build an immune system so the antibiotic will not be effective anymore
• Cell Wall


  • Peptidoglycan: The outermost structure of many prokaryotic cells. Some species of bacteria or archaea may lack a cell wall altogether
• Capsule


  • Hydrated Polysaccharide found outside the cell wall of many bacteria, providing protection against antibacterial agents and preventing desiccation
• Nucleoid


  Also known as nuclear zone or nuclear region where the prokaryotic chromosome is folded and packed, usually not bound by a nuclear membrane
• Plasmids


  Small, independently replicating circular double stranded DNA molecules that confer additional traits to the bacteria such as resistance to antibiotics
• Flagella


  Thin, rigid, curved rods made up of flagellin protein, movement is proton driven
• Pili (singular Pilus)


  Thick tubular rod-like protein structures used to exchange genetic materials during reproduction (conjugation)
• Fimbriae


  Tiny bristle-like fibers emerging from the surface of bacterial cells used to attach to the host cell
• Inclusion bodies are particles of aggregated protein that store substances present in excess which can serve as reserve metabolic substrate
• Prokaryotic Ribosomes


  • Have a small subunit (30S) and a large subunit (50S), forming 70S sediments
• Eukaryotic Ribosomes


  • Have a small subunit (40S) and a large subunit (60S), forming 80S sediments
• Svedberg units are named in honor of the scientist Theodor Svedberg
• Theodor Svedberg won the 1926 Nobel Prize for Chemistry for his research on colloids and proteins using the ultracentrifuge
• Endoplasmic Reticulum


  • A series of interconnected membranous sacs and tubules that modifies proteins and synthesizes lipids
• Smooth ER


  • Few or no ribosomes
• Rough ER


  • Ribosomes are attached to cytoplasmic surfaces
• Rough ER Lumen


  • Hollow space where newly synthesized proteins are transferred and modified
• Golgi Apparatus


  • A series of flattened membranes where sorting, tagging, packaging, and distribution of lipids and proteins take place
• Vesicles


  • Transport smaller membrane-bound sacs that can fuse with either the plasma membrane or other membrane systems within the cell
• Peroxisomes


  • Small, round organelles enclosed by a single membrane that carry out oxidation reactions
• Glyoxysomes


  • Specialized peroxisomes in plants converting stored fats to sugar
• Special Parts in Animal & Plant Cells

  • Animal Only: Centrosome, Lysosomes
  • Plants Only: Cell Wall, Chloroplast, Central Vacuole
• Centrosome


  • Microtubule-organizing center near the nuclei of animal cells
• Lysosomes


  • Cell's garbage disposal, containing enzymes that aid in breakdown
• Cell Wall Structure


  • Main component: cellulose microfibrils
• Central Vacuole


  • Storage of water and molecules, regulates water concentration
• Chloroplast


  • Bounded by double membrane called the chloroplast envelope, involved in photosynthesis
• The unified cell theory states 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