2. We see an enormous diversity of eyes in Kingdom Animalia. Until recently it was postulated that eyes must have evolved at least 40 times independently. Explain how the discovery of Pax6 (and its homologs such as eyeless ) has overturned this idea in favor of genes for eye development being present in an ancestor to all bilateral organisms.

In dna, only the_ varies from one nucleotide to another. base phosphate sugar amino acid

Molecular models of two different substances are shown below. in the molecule on the left, the oxygen atom pulls on electrons more strongly than the hydrogen atoms. in the molecule on the right, the two oxygen atoms pull on the shared electrons with the same strength. water molecule, h,o oxygen molecule, oz when the two substances are put in the same container, they do not attract each other. why does this happen? a. they both contain oxygen. b. one is polar and one is nonpolar. c . they are both polar. d. they contain different elements.

The picture showed normal blood cells which are around and sickle cells which appear much longer people with sickle-cell suffer from the sickle cell anemia which is inherited diseaseit is caused by a change in gene responsible for production of hemo goblin this type of change is known as an