Microscopy, Prok Vs Euk (Lecture 3) Flashcards
Concepts of electron microscopy
- Higher resolution than light microscopy since electrons have short wavelengths compared to visible light
- Requires specimen to be fixed
- Specimens are stained with heavy metal, which electrons can’t pass through (gold)
About Transition electron microscopy (TEM)
- Thin sections made using a microtome
- Images appear black with white background
- Light regions are where electrons passed through the sample and hit the camera
- Dark regions represent areas where electrons did not pass through to hit the camera
About Scanning electron microscopy (SEM)
- No sectioning needed, just coat sample with heavy metal (usually gold)
- The 3D contours of the surface are visualized by scanning an electron beam across the specimen
Types of Prokaryotes?
- Bacteria
- Archaea
Types of Eukaryotes?
- Animals
- Plants
- Fungi
- Protists
What cells are bigger? Prok or euk?
Eukaryotes
What are the 5 elements common to all living cells?
- Genetic information paradigm: DNA -> RNA -> Protein
- Plasma membrane
- Cytoplasm
- Ribosomes
- Cytoskeleton
What is the process of Genetic information paradigm? (DNA, RNA , protein)
DNA (Deoxyribonucleic acid) transcribes RNA polymerase and becomes RNA (Ribonucleic acid) which then gets translated through ribosomes where protein is created
What are Prokaryotes organization of DNA?
- DNA is found in the Nucleoid
- Single, circular chromosome and often several circular plasmids
What are Eukaryotes organization of DNA?
- DNA housed in nucleus
- One or more linear chromosomes
Where are genes arranged?
Along chromosomes
Where does the Translation of mRNA into protein take place?
Cytoplasm
What is the plasma membrane structure?
- Phospholipid bilateral + thousands of protein, phospholipid molecule made up of a hydrophilic head and hydrophobic tail
What is Cytoplasm? (Juice)
- Consists of cytosine + organelles
- Cytosol is the aqueous liquid
~mostly water
~full of macromolecules + smaller molecules (ions, metabolites)
~metabolic activities
~signal transduction
About Ribosomes?
- A highly organized machine consisting of proteins and rRNA. It’s more like an enzyme than an organelle
- reads the sequence of mRNAs to coordinate their translation into proteins
- prokaryotic ribosomes are a bit ambler but do the same thing
