How can the genetic code with just letters carry the instructions for just 20 amino acids?

Color blindness is a recessive trait. the gene for color blindness is on the x chromosome. the family tree below shows the trait of color blindness. the only unknown is the mother in the first generation

Which of these is a provisioning service people get from the ocean

Land conservation is a worldwide priority. there are several methods to prevent the loss of land due to a variety of reasons. which method is not a way to conserve land? a) sea walls b) rainwater harvesting c) limits on clear cuts of forests d) cut and burn methods of clearing land