Molecular and Cellular

• What is one of the learning outcomes regarding cells?


  Cells vary enormously in appearance and function.
• What do all living cells have in common regarding their chemistry?


  All living cells have a similar basic chemistry.
• How do living cells replicate themselves?


  Living cells are self-replicating collections of catalysts.
• From what did all living cells apparently evolve?

  All living cells have apparently evolved from the same ancestral cell.
• What role do genes play in cells and organisms?


  Genes provide instructions for the form, function, and behaviour of cells and organisms.
• What are the oldest known fossils?

  Stromatolites.
• How are stromatolites formed?


  They are formed by the accumulation of sedimentary layers on bacterial mats.
• How far back do stromatolites date?


  They date back to 3.5 billion years ago.
• What was the state of life on Earth from 3.5 to 2.1 billion years ago?


  Prokaryotes were Earth's sole inhabitants during that time.
• What is the common ancestry of all cells linked to?

  All cells are linked to the 'Ancestral Prokaryote.'
• What is the Central Dogma of molecular biology?


  The sequence of nucleotides in a gene is transcribed into RNA, which is then translated into a protein.
• What must cells do to replicate themselves?


  Cells must replicate their genetic "info carrying" material.
• What do cells need to take up or synthesize to live and replicate?


  Cells need to take up and/or synthesize the nutrients they need to live and replicate.
• What are prokaryotic cells known for?


  They are the most diverse and numerous cells.
• Into how many domains are prokaryotic cells divided?


  Prokaryotic cells are divided into 2 domains: 'Bacteria' and 'Archaea.'
• What is a characteristic of prokaryotic organisms?


  They can colonize every habitat.
• What type of structures do prokaryotic cells have?


  Some prokaryotic cells have compartmentalization.
• What do prokaryotic cells share with eukaryotes?


  They contain many homologous processes to those found in eukaryotes.
• Where is most of the DNA located in eukaryotic cells?


  The nucleus contains most of the DNA.
• When do chromosomes become visible in a cell?


  Chromosomes become visible when a cell is about to divide.
• What is the role of the Endoplasmic Reticulum (ER) in eukaryotic cells?


  The ER produces many of the components of eukaryotic cells.
• What is the structure of the Golgi apparatus?


  The Golgi is composed of flattened, membrane-enclosed discs.
• What is the cytoskeleton?


  The cytoskeleton is a network of protein filaments that criss-crosses the cytoplasm of eukaryotic cells.
• What are the three types of microscopy techniques to explain basic concepts and uses for?


  • Conventional light microscopy
  • Fluorescence microscopy
  • Electron microscopy
• What is the maximum magnification of conventional light microscopy?


  Conventional light microscopy can magnify up to 1000x.
• What is the resolution limit of conventional light microscopy?


  It can resolve details as small as 0.2μm (200nm).
• What are the three things used for viewing cells in a light microscope?


  Bright light focused on the specimen, careful specimen preparation, and an appropriate set of lenses.
• What are the two systems used for viewing living cells?

  Phase-Contrast Optics and Interference-Contrast Optics.
• What is histology?


  Histology is the study of tissues.
• What is the purpose of fluorescence microscopy?


  Fluorescence microscopy uses fluorescent dyes to stain cells.
• How does fluorescence microscopy filter light?


  It passes light through two sets of filters to excite the fluorescent dye.
• What is GFP and its significance?


  GFP (Green Fluorescent Protein) comes from a jellyfish and is used for live cell imaging.
• What does super-resolution fluorescence microscopy achieve?


  It allows fluorescence microscopes to break the usual resolution limitation of 200nm.
• How does scanning electron microscopy work?


  It scans a specimen coated with a thin film of heavy metal using a beam of electrons.
• What is the resolution range of scanning electron microscopy?


  It can resolve between 3nm - 20nm.
• What is the purpose of transmission electron microscopy?


  It uses a beam of electrons to create high-resolution images of very thin specimens.
• What is the maximum magnification of transmission electron microscopy?


  It can achieve magnification up to a million-fold.
• What is the resolution limit of transmission electron microscopy?


  It can resolve as small as 1nm.