Bioengineering GIM Course

• What is the modern cel theory?

  • The Cell is the smallest unit in all living orgnisms
  • All living organisms are made of cells whether unicellular or multicellular
  • All cells come from pre-existing cells
• Cell Theory was proposed by Matthias Schleiden (1838) and Theodor Schwann (1839)
• What are Eukaryotes?

  Organisms with cells that have a nucleus and membrane-bound organelles.
• What are prokaryotes?

  Single-celled organisms without a nucleus or membrane-bound organelles.
• What are the 4 things all cells share?

  Cell membrane, cytoplasm, DNA, ribosomes
• What is a capsule? (Prokaryotic)

  Additional outer layering that protects the cell when it is engulfed by other organisms.
• What is a cell wall?

  A rigid layer that surrounds the cell membrane of plant cells and provides support and protection.
• What is a Pili? (Prokaryotic)

  Hair-like structures on the surfaceof the cell that is attached to other bacterial cells. Shorter pili called fimbriae hellp bacteria attach to surfaces
• How do prokarytic cells reproduce?

  Binary fission.

  During binary fission, the single DNA molecule replicates and the original cell is divided into two identical cells.
• What does a eukaryotic cell look like?

  Cytoskeleton, Endoplasmic reticulum, Gogi apparatus, Ribosomes, Mitochondria, Nucleus, Nucleolous, Lysosomes, Vacuoles
• Golgi Apparatus:

  • Made up of flat disc-shaped structures called cisternae
  • Absent in red blood cells of humans and sieve cells of plants
  • Arranged parallel and concentrically near the nucleus
  • Important site for the formation of glycoproteins and glycolipids
• Ribosomes:

  • Main site for protein synthesis
  • Composed of proteins and ribonucleic acids
• Mitochondria:

  • Also known as the "powerhouse of cells" for energy production
  • Consists of an outer membrane and an inner membrane with folds called cristae
  • Help in the regulation of cell metabolism
• Nucleus:

  • Nucleoplasm contains DNA and proteins
  • Nuclear envelope has two layers: outer and inner membrane, both permeable to ions, molecules, and RNA material
• Nucleolus:

  • Found within the nucleus for ribosome production
• Lysosomes:

  • Possess hydrolytic enzymes to digest protein, lipids, carbohydrates, and nucleic acids
• Vacuoles:

  • In animal cells, generally small and help sequester waste products
  • In plant cells, help maintain water balance
• Mitotic Phase is the stage where a cell divides
• Meiosis is the division of a single nucleus into two genetically identical daughter cells
• The division of the nucleus in mitosis involves the P-MAT process (Prophase, Metaphase, Anaphase, Telophase)
• Cytokinesis is the separation of the cytoplasm and the new nuclei into daughter cells
• Prophase:

  • Chromatids condense becoming chromosomes
  • Nucleolus disappears
  • Centrioles separate and start moving to opposite ends of the cell
  • Spindle begins to form
  • Centrioles move to opposite poles
  • The spindle is completely formed
• Metaphase:

  • Chromosomes are aligned in the middle of the cell at the metaphase plate
  • Centrioles move at polar ends and project spindle fibers to connect to each chromosome
• Anaphase:

  • The paired chromosomes (duplicated sister chromatids) separate
  • Separated chromatids move to separate poles
  • Partial division of the cytoplasm begins
• Telophase:

  • Chromosomes are at the poles
  • Chromosomes uncoil to turn back into chromatin
  • Nuclear envelope reforms
  • Spindle fibers disappear
• Cytokinesis:

  • Occurs at the end of mitosis
  • In animal cells, a cleavage furrow forms that separates the daughter cells
  • In plant cells, a cell plate separates the daughter cells
• Meiosis:

  • Type of cell division where a single cell divides twice and produces four daughter cells
  • Daughter cells contain half the amount of genetic material and are known as sex cells (gametes)
  • Daughter cells are haploid, consisting of half the number of chromosomes of the parent cell
• Cellular Respiration:

  • Series of metabolic processes within a cell
  • Biochemical energy is harvested from an organic substance (e.g. glucose) and stored in an energy-carrying biomolecule (e.g. ATP) for energy-requiring activities
• Stem Cells:

  • Have the potential to renew themselves and develop into many different cell types in the body during early life and growth
  • When a stem cell divides, the resulting daughter cells may be both stem cells, a stem cell and a more differentiated cell, or both more differentiated cells
  • The balance between these types of divisions to maintain stem cells at an appropriate level within a given tissue is not well known
• Stem Cells can:

  • Increase understanding of how diseases occur
  • Generate healthy cells to replace cells affected by disease (regenerative medicine)
  • Test new drugs for safety and effectiveness