Lecture 1 - The Cell Flashcards
What do you have to do to look at something at the cellular level?
- Preserve the tissue through fixation (Light/Electron)
- Embed and Section
- Stain
How to preserve the tissue for Light Microscopy
Formalin
How to preserve the tissue for Electron Microscopy
Glutaraldehyde + Osmium Tetroxide
How to embed for Light Microscopy
Paraffin (1-10um sections)
How to embed for EM
Resin (100nm sections)
How to stain for Light Microscopy
Hematoxylin and Eosin (H&E)
How to stain for EM
Osmium tetroxide
Hematoxylin stains _____ this color: ____
Acids, blue
Eosin stains _____ this color: _____
Bases, pink
What parts of the cell are acidic?
DNA
RNA
Ribosomes
What inside the cell would be considered basic?
Collagen
Proteins
Advantages of Light Microscopy?
Many special stains
Many special techniques
Determining acids and bases
Resolving power of LM
200nm
Resolving power of EM
50pm
What are plasma membranes made of?
Cholesterol
Phospholipids
Proteins
Carbohydrates
What is the purpose of the phos bilayer? (2)
- Allows lipid soluble molecules to freely diffuse across
2. Prevents water soluble molecules from freely diffusing across
What is the function of cholesterol?
-keeps the membrane fluid
What makes up the glycocalyx?
Carbohydrates
What is the function of the glycocalyx?
Identification for immune cells to recognize self from non-self
Distinguishing features of mitochondria?
- Elongated structure
- Inner/outer mitochondrial membrane –> cristae
- matrix granule
What organelles are involved w/ the synthesis of integral membrane and exported proteins?
- Rough ER
- Golgi
- Ribosomes
- Secretory Vessicles
If mRNA goes through free ribosomes, the mRNA is destined as _____
Cytosolic proteins
If mRNA goes to the ER, the mRNA is destined as ____
Membrane, secreted proteins
What color will a cell be stained that contains a lot of ribosomes?
Blue - Hematoxylin
RNA = acidic -> pics up basic stain
What face of the golgi do transport vessicles come in?
cis face
What face of the golgi do transport vessicles leave?
trans face
What stain do you use for lysosomes?
Toluidine Blue
Components of cytoskeleton
microfilaments - 7nm
intermediate filaments - 10-12nm
microtubules - 24nm
What makes up microfilaments?
Actin
What makes up microtubules?
Tubulin
What makes up intermediate filaments?
Keratin
Neurofilament protein
Lamin
Vimentin
Function of microfilaments? (4)
- Provide stiffness/structure/shape to membrane
- Responsible for protrusions, such as microvilli and phogocytic projections
- Provide motility for cells (macrophages/neutrophils/mast cells)
- Contraction of muscle cells
Actin attaches to the ____ end and releases from the _____ end.
+, -
What causes cellular dystrophy?
Mutation in dystrophin causes the connection between the actin cytoskleton and the plasma membrane to be lost
Microtubules attach at the ____ end and release at the _____ end.
+,+
What is the function of microtubules?
- Vessicle movement and organelle placement
- Mitotic spindle
- Cytoskeleton in cilia and flagella (movement)
What are centrosomes made of?
- Centrioles (microtubule triplets)
- Cloud of protein
Nucleate microtubules and anchor their (-) ends.
What does MTOC and what is it?
- Microtubule-organizing center
2. Centrosome
