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What is histology?

   Started at:

Membranes

You gotta have skin.
All you really need is skin.
´Cause skin is the thing
that keeps your insides in.
      Allan Sherman
  • All cellular membranes are based on the lipid bilayers
  • Cell membranes are dynamic, fluid structures
  • Membranes serve to separate incompatible processes
  • Enzymes are often imbedded into membranes so that membranes are sites for specific biochemical reactions
  • Proteins associated with the membrane are either stuck on it (peripheral) or stuck into it (integral)
  • Membrane proteins may act as transport molecules, receptors, adhesion molecules, recognition sites, etc
  • Coetzee et al p12-14
  • Stevens & Lowe p10-14
  • Wheater's Functional Histology p4-7 (3e Ed) of p6-9 (4e Ed)

Cytoplasm

 
  • Consists of an aqueous gel and contains the organelles
  • Rich in enzyme systems
  • Coetzee et al p11
  • Stevens & Lowe p14

Nucleus

 
  • Bounded by a double nuclear membrane
  • Contains the genetic material (DNA) as chromatin
  • Contains the nucleolus which manufactures ribosomes and rRNA
  • Moves substances in and out through nuclear pores
  • Coetzee et al p29-39
  • Stevens & Lowe p15-17

Endoplasmic reticulum

 
  • Proteins for export are synthesized in the GER
  • SER is responsible for lipid synthesis and detoxification
  • Coetzee et al p15-16 & 19
  • Wheater's Functional Histology p12-15
  • Stevens & Lowe p19-20

Ribosomes

 
  • Particle composed of RNA and protein
  • Essential for protein synthesis
  • Ribosomal subunits and associated proteins are synthesized in the nucleolus
  • Contain 3 RNA-binding sites: 1 for mRNA and 2 for tRNA
  • Maybe associated with ER or freely suspended in cytoplasm as polyribosomes
  • Coetzee et al p14-15
Quiz 2:3  
  Objective: answer 5 questions correctly.
  • Membranes
    Are stuck into proteins
    Are based on lipid bilayers
    Transport proteins
    Are imbedded into proteins

  • Cytoplasm
    Contains virii
    Contains bacteria
    Containes organelles
    Contains peripheral associated membrane proteins

  • The nucleus
    Export GER
    Is responsible for detoxification
    Moves substances through the cell membrane
    Contains DNA

  • Endoplasmic reticulum
    Do lipid synthesis and detoxification
    Move substances through nuclear pores
    Consists of an aqueous gel

  • Ribosomes are synthesized in
    The Golgi-apparatus
    The nucleus
    The nucleolus
    The cytoplasm
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© julie 202 marius loots