Microscopy and Cell structure Flashcards
Define the limit of resolution
The minimum distance two objects can be distinguished at
What is limit of resolution proportional to?
Wavelength
What is the theoretical limit of resolution for a light microscope?
0.2 micrometres
What is the theoretical limit of resolution for an electron microscope?
0.002nm
What feature of the phospholipid bi layer structure makes it selective, and in what way?
Phospholipid molecules are ampipathic - Hydrophillic phosphate groups on outside, hydrophobic lipids on inside. This means they are relatively impermeable to most water soluble molecules.
What feature of phospholipid bilayer allows it to mediate the majority of its functions?
Protein molecules dissolved within the membrane
What is the structure of the golgi?
Saucer shaped stacks of cisternae
How do vesicles get to golgi, and where do they fuse?
Bud off from Rough Endoplasmic reticulum and fuse with the convex cis face of the golgi body
What feature of golgi bodies allows proteins to move through it?
Its polarity
In which direction do protein migrate through golgi?
From convex cis phase to the the concave trans face of the stack
What are the four function of the golgi?
Modify, sort, concentrate and package proteins synthesised on rough endoplasmic reticulum
What two destinations do vesicles budding from the golgi have?
Either lysosome assembly or secretion
What is the glycocalyx, and what is their function?
The cell “coat made up of oligosaccharide and polysaccharide side chains on the outiside of the plasma membrane Give the cell specificity
What are the 7 functions of the plasma membrane of a cell?
Selective permeability Transport of materials along the cell surface Endocytosis Intracellular recognitio Exocytosis Signal transduction Intercellular adhesion
What are the major functions of the nucleus?
1) Stores the cells DNA 2) It coordinates the cell’s activities, metaolism, growth, protein synthesis an mitosis