Topic 1.2:  Ultrastructure of Cells

Essential Idea: Eukaryotes have a much more complex cell structure than prokaryotes.
At SHS, Topic 1.2 is taught in the following class unit(s):

Statements & Objectives:

1.2.U1  Prokaryotes have a simple cell structure without compartmentalization.
  • Outline the major differences between prokaryotic and eukaryotic cells.
  • List the functions of the following structures of a prokaryotic cell:  cell membrane, nucleoid, plasmid, cytoplasm, ribosome, cell wall, pili, capsule, and flagella.
  • Define extracellular.
  • Contrast the size of eukaryotic and prokaryotic ribosomes.
1.2.U2  Eukaryotes have a compartmentalized cell structure.
  • State the meaning and advantages of eukaryotic cells being  “compartmentalized.”
1.2.U3  Prokaryotes divide by binary fission.
  • Define asexual reproduction.
  • Outline the four steps of binary fission.​
1.2.U4  Electron microscopes have a much higher resolution than light microscopes.
  • Define resolution.
  • Compare the maximum resolutions of a light microscope with those of an electron microscope.
  • List three example structures that are visible with electron microscopes but not with a light microscope.​
1.2.A1  Structure and function of organelles within exocrine gland cells of the pancreas.
  • State the function of an exocrine gland cell.
  • Describe the function of the following structures in an exocrine gland cell:  plasma membrane, nucleus, mitochondria, Golgi apparatus, lysosomes, vesicles and endoplasmic reticulum.
1.2.A2  Structure and function of organelles within palisade mesophyll cells of the leaf.
  • State the function of a palisade mesophyll cell.
  • Describe the function of the following structures in a palisade mesophyll cell:  cell wall, plasma membrane, chloroplasts, vacuole, nucleus, and mitochondria.​
1.2.S1  Drawings of the ultrastructure of prokaryotic cells based on electron micrographs.
  • Explain why the ultrastructure of prokaryotic cells must be based on electron micrographs.
  • Draw the ultrastructure of E.coli, including the cell wall, pili, flagella, plasma membrane, cytoplasm, 70s ribosomes, and nucleoid with naked DNA.​
1.2.S2  Drawings of the ultrastructure of eukaryotic cells based on electron micrographs.
  • Recognize features and identify structures in micrographs of eukaryotic cells (inclusive of the plasma membrane, cytoplasm, free 80s ribosomes, nucleus, rough endoplasmic reticulum, Golgi apparatus, lysosome, mitochondria, chloroplast, vacuoles, vesicles, centrioles, microtubules, cilia, flagella and cell wall).
  • Given a micrograph, draw and label the ultrastructure of a eukaryotic cell.​​
1.2.S3  Interpretations of electron micrographs to identify organelles and deduce the function of specialized cells.
  • Explain why cells with different functions will have different structures.
  • Identify ultrastructures visible in a micrograph of a eukaryotic cell.
  • Given a micrograph of a cell, deduce the function of the cell based on the structures present.​​
1.2.NOS  Developments in scientific research follows improvements in apparatus- the invention of the electron microscopes led to greater understanding of cell structure.
  • With reference to a specific example, explain how an improvement in apparatus allowed for greater understanding of cell structure.

In the News:
"When we try to pick out anything by itself, we find it hitched to everything else in the Universe."  -  John Muir,   1911