Cell Biology Answers

what are the procedure to test for the presence of starch

The haemoglobin molecule is designed to transport oxygen around the body. With reference to the different levels of organisation of polypeptides explain how this molecule achieves its function.

Animal cells are surrounded by a cell plasma membrane which apart from protecting the cell contents also moderates what enters and leaves its internal environment.

Describe and explain clearly how the cell transports the following substances across the membrane :

i) water

ii) sodium and potassium ions

iii) glucose

iv) enzymes to be used by other cells in the body

You purify plasmid from E.coli and obtain 100µl of DNA at 0.75mg/ml. You want to amplify the insert contained in the plasmid by PCR. You need to add 50pg of plasmid DNA to your PCR reaction.



-How much of the original solution do you need to add?



- Is this practical given the minimum volume you can accurately pipette is 1µl? Draw up a dilution scheme using 1ml tubes that is.



- Your PCR reaction volume is 25µl and we want to keep the template 10% or below the total volume.

What are the physical forces responsible for the movement of an uncharged particle and a charged particle across a biological membrane.

c) What is the physical effect of partial dehydrogenation?

Why oogonial cells degenerate?