Drosophila fruit flies are often used as model organisms in genetic research. In Drosophila, eye color is determined by genes on the sex chromosomes, and red eyes (W) are dominant to white eyes (w). Figure 1
shows an example of Drosophila sex chromosomes with alleles for eye color. Figure 2 is a pedigree showing
the inheritance of eye color in Drosophila over four generations. Figure 3 is a Punnett square depicting a cross
between two fruit flies.
A Based on Figure 1, describe a difference between a Y chromosome and an X chromosome.
B. In Figure 1, both the female and the male have one recessive allele, Predict whether the female and
male will express the same trait and justify your claim using evidence from Figure 1.
C. Based on Figure 2, describe the pattern in a pedigree for an X-linked recessive trait.
D. Based on Figure 3, explain why all male offspring are white-eyed and all female offspring are red-eyed.

We can plant more trees and plants.

Proteins are the workhorses of the cell, controlling virtually every reaction within as well as providing structure and serving as signals to other cells. proteins are long chains of  amino acids  , and the exact sequence of the amino acids determines the final structure and function of the protein. instructions for that sequence are encoded in  genes  . to make a particular protein, a messenger ribonucleic acid (mrna) copy is made from the gene (in the process called  transcription  ), and the mrna is transported to the  ribosome  . protein synthesis, also called  translation  , begins when the two ribosomal subunits link onto the mrna. this step, called initiation, is followed by elongation, in which successive amino acids are added to the growing chain, brought in by transfer rnas (trnas). in this step, the ribosome reads the  nucleotides  of mrna three by three, in units called  codons  , and matches each to three nucleotides on the trna, called the anticodon. finally, during termination, the ribosome unbinds from the mrna, and the  amino acid  chain goes on to be processed and folded to make the final, functional protein