Answer: Faster-evolving gene sequences provide better data for comparisons among close relatives, whereas very slowly evolving sequences work best for distantly related tax.
Once the Earth was full of water (ocean) after volcanic activities the mainland became land ( sorry about my english i am hungarian and i am still learning the language )
The hemoglobin holoenzyme (active enzyme) is a complex of an iron ion and 4 subunits- 2 hemoglobin alpha and two hemoglobin beta. People with sickle cell disease have mutated beta hemoglobins. The mutation is a single nucleotide exchange, that changes the 6th amino acid of protein primary struture - a Glutamic acid into Valine. This one alteration changes the tree dimentional structure of hemoglobin beta so, that it forms lond fibres that disrupt the normal circular form of the red blood cells.
Okay First off what are the problems and what are the hardest ones?
Explanation:
Simple Diffusion across the Cell (Plasma) Membrane The structure of the lipid bilayer allows only small, non-polar substances such as oxygen and carbon dioxide to pass through the cell membrane, down their concentration gradient, by simple diffusion.
