A. He should add shells that are different colors, but the same size and type, to the tank and observe which shells the hermit crabs choose.
Durning an experiment you need to keep everything the same but only change the certain things based on your theory.
Such as how the student wanted to see if the color attracted the crab. If he had changed the size and type of the shell then the crab would have chosen the bigger one as they tend to grow into larger shells.
Brown eye-color is dominant while the blue-eye color is recessive. Therefore, the homozygous for brown color is BB and the homozygous for brown color is bb. Thus, the heterozygous will be Bb (brown color). Since James has blue colored eyes a child of Jenna (brown color) and bill (blue color) then it means Jenna is heterozygous (Bb). Jenna is described as being a carrier of the allele for blue eyes.
The bryophytes, which include liverworts, hornworts and mosses, reproduce both sexually and vegetatively. The gametophyte is the most commonly known phase of the plant. All are small plants found growing in moist locations and like ferns, have motile sperm with flagella and need water to facilitate sexual reproduction.
