Practical 1 - fish Flashcards
Why is nuclear DNA advantageous for evolutionary studies?
It evolves more slowly than non-nuclear genes
Role of SDS in SDS-PAGE
Confers a negative charge to the proteins so that they will migrate through the gel according to their mass rather than their native charge and SDS coated proteins move away from the negative charge towards the positive charge
Why do bands vary in thickness?
Protein variables, depends on how you load the protein, issues in extraction
What happens if there is too much protein in the fish muscle sample?
It won’t bet broken down properly by the buffer due to the SA:V
What happens if the sample of fish is too big?
The sample might also include other macromolecules such as carbs and lipids which can interfere with the lysis buffer and make the bands less clear
What can you add to improve sharpness of bands?
DTT
How can you make a sample better?
Centrifuge it to get rid of non-proteins
How to make background noise disappear?
Destain for longer
Why plot a pre-stained ladder on log paper?
Act as a reference to calculate the length of each band
What are the components of sarcomeres?
Actin and myosin filaments
What do variations in muscles reflect?
Muscles adapted to different niches, environments or physiological stresses
Fish superclass
Gnathostoma (jawed vertebrates inc all tetrapods)
What are hyperotreti (hagfish)?
Craniates (animals with skulls) but are not vertebrates as they have no backbone
What are hyperoartia (lampreys)?
very primitate vertebrates with no jaw
What are chondrichthyes?
Cartilaginous fish
