Biology Lesson 3

• All life forms, except viruses, consist of cells
• Cell


  The basic functional unit of life
• Without metabolism life won't exist
• There are trillion of cells
• Humans doesn't die easily because there is a cellular reproduction
• Apoptosis


  Program cell death
• Apoptosis in fetus development

  1. Apoptosis eliminates cells that cause fingers to stick together

  2. Results in separate fingers in newborn baby
• Polydactyly is a condition in which a baby is born with one or more extra fingers
• Organ


  Different from organelles
• Organelles


  Little organs inside the cell, visible in the protoplasm
• Protoplasm


  The living, gel-like substance inside the cell
• Cytoplasm


  In eukaryotic cells, all the material inside the cell except the nucleus

  
• Cell was first discovered by Robert Hooke


  1674
• The cell theory states: 1) All living things are composed of cells and cell products, 2) A single cell is the smallest unit that exhibits all the characteristics of life, 3) All cells come only from preexisting cells
• Cork cell


  The cell structure first observed by Robert Hooke
• Cell division


  The process where new cells replace old ones, carried out by stem cells
• Prokaryotic cell


  Cells without a true nucleus
• Eukaryotic cell


  Cells with a true nucleus
• Differences between prokaryotes and eukaryotes

  • Prokaryotes: simple structure, no prominent nucleus, small size, cell wall has peptidoglycan, small ribosomes, unicellular, no organelles
  • Eukaryotes: complex structure, prominent nucleus, large size, cell wall has chitin or cellulose, large ribosomes, unicellular or multicellular, membrane-bounded organelles

  
• Similarities between prokaryotes and eukaryotes

  • Contains DNA
  • Contain ribosomes
  • Have cell membrane
  • Contain cytoplasm

  
• Bacillus/Bacilli


  Rod-shaped bacteria (singular/plural)
• Coccus/Cocci


  Round-shaped bacteria (singular/plural)
• Peptidoglycan


  Gel-like coat of bacteria that makes them resistant to antibiotics
• Golgi apparatus was made by Camilo Golgi
• Animals don't have cell walls, only plants do
• Mitochondria


  Powerhouse of the cell, where cellular respiration occurs
• Cristae


  Single folds in the mitochondria
• Crista


  Multiple folds in the mitochondria
• Mitochondria are more abundant in organs that require more energy, like muscles
• Golgi apparatus


  Modifies, checks, and packages cell products
• Golgi apparatus processing of proteins

  1. Receives proteins from ER

  2. Checks if components are sufficient

  3. Packages proteins in transport vesicles

  4. Delivers packaged proteins to cell membrane and other areas
• Transport vesicle


  Vesicles that detach from Golgi apparatus to deliver cell products
• Endoplasmic reticulum


  Manufacturing area of the cell
• Cisface


  Entrance of Golgi apparatus
• Transface


  Exit of Golgi apparatus where products are shipped out
• Golgi apparatus was named after its creator, Camilo Golgi
• Rough endoplasmic reticulum


  Manufactures proteins due to presence of ribosomes
• Smooth endoplasmic reticulum


  Manufactures cell products like carbohydrates and lipids, and detoxifies harmful materials
• Ribosomes


  Carry out protein synthesis, repair damaged tissues, act as catalysts, and communicate through proteins
• Central dogma of molecular biology

  Genetic information flows from DNA to RNA to protein, or RNA directly to protein