1. The phrase Darwin used to describe his broad theory of evolution is ''descent with modification.
2. All of life is related through common ancestry, accounting for the Unity.
The TYR, TRP2, and TRP1 genes are located next to each other on a single chromosome and are organized into an operon is most likely to be accurate.
The option a is correct.
Explanation:
The genes for the Tyrosinase, TRP2 and TRP1 are located on the same chromosome and are operons. These are operons because they are controlled by same transcription factors on mRNA.
Tyrosinase enzyme is important for the synthesis of melanin, eye pigments and hair colour. The synthesis of all these is completed in three distinct reactions catalysed by TRP1, TRP2 and Tyr genes. These work as operon and the protein product is almost 40% similar of the three genes.
The amount of melanin production depends on tyrosinase enzyme activity of all the three genes.
The genetic regulation is done by operons.
Answer:
As the diagram is not given, hence let's generally describe the movement of molecules along the cell membrane.
Molecules can either pass through the cell without using energy through the process of passive transport. An example includes molecules of oxygen.
Molecules which are large and un-polar cannot move through the cell membrane easily. These molecules will require energy to move through the cell membrane. These molecules might move in with the help of the carrier or facilitated proteins. Examples include molecules of glucose.