Thanks guys for the help!
@Thushan, but wouldn't each twin accumulate different mutations? Like maybe in their early stages two twins would be identical, but overtime would they not accumulate different mutations, and doesn't environmental factors affect their phenotypes?
Also wouldn't epigenetics cause some genes to be switched on and off over time?
Mutations: Not bad thinking, but no. Sure, they twins will accumulate heaps of mutations, but these generally don't affect all cells. Only mutations in the zygote are passed onto all cells. So, unless mutations are accrued in the zygote (they're normally not) the twins will have identical genomes.
It's important to note that not every cell has exactly the same genome. They will be very slightly different because individual cells can accrue mutations and therefore will pass on those mutations to any daughter cells. Just because one cell gets a mutation, however, doesn't mean that all cells in the body get it. Naturally, mutations earlier on in development are more likely to be spread around the body because more cells are descended from that cell in which the mutation has occurred.
Epigenetics: their epigenetics would be nearly identical because twins tend to grow up in the same environments and because they're descended from the same mother, grown up in the same womb and so on. Sequencing of genomes also entirely ignores epigenetics. When you sequence something, you don't get any sense of gene expression etc.*
Environment: yes, environmental factors will change phenotypes. That's why identical twins never look the same. As far as sequencing though, why would this matter? Environmental factors don't change their genomes...
*for the real pedants, yes I realise that epigenomes are heritable but VCE...
hey
do we need to know the active and passive transport in plasma membrane?
Like how the passive transport respectively goes against its concentration gradient?
and why the plasma membrane is semi-permeable?
Yes