Answer:
Hershey and Chase demonstrated that genetic material is contained in the DNA molecule. By using bacteriophages they observed that DNA, but not proteins, contains the genetic material. These researchers tagged DNA with radioactive phosphorus and then separated bacteria and protein phages by centrifugation, observing that bacterial pellet was radioactive
A single gene disorder is one that's known to be caused by a single gene. Multiple gene disorders, however, can be caused by multiple gene combinations and other factors. Dominant genes are always expressed in the offspring, while recessive genes are only expressed if the offspring recieves the recessive gene from both parents. Sex-linked genetic disorders occur most often in men, and are caused by a single-gene disorder gene being on the X chromosome but not the Y, so that the offspring needs only one recessive gene to have the trait/disorder.
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The type of fertilization that one would expect to find in this specie is EXTERNAL FERTILIZATION. External fertilization is the type of fertilization in which the male sperm fertilize the female eggs out of the female's body. This type of fertilization usually occur in aquatic environment.