Science Meiosis Mitosis study guide

Review Pg. 159 DNA is made of only four subunits, which are known as nucleotides. The four parts types of nucleotides adenine, thymine, guanine, and cytosine and they each have slightly different shape. Each of this contain three different types of materials a sugar, a phosphate, and a base. A and T pair together to form a DNA molecule and G and C together form a DNA molecule. The shape that Rosalind images were was a spiral shape.

DNA unites all organisms’ means that DNA is the main source in the cell and has the most important job, therefore uniting the cells. The DNA of all living organisms have the same structure and code. 80 percent would be the percentage of Guanine because Cytosine is 20 percent and 80 plus 20 equals 100. Pg. 164 Three types of mutations are insertion, deletion, and substitution. Mutations can lead to changes in the structure of an encoded protein or to a decrease or complete loss in its expression.

Because a change in the DNA sequence affects all copies of the encoded protein, mutations can be particularly damaging to a cell or organism. The type of mutation that causes sickle cell anemia is called substitution. In the recessive trait the sex cell will occur throughout the body. Pg. 167 1. In selective breeding you are relying on the natural random distributions of genes in the mating process. By rewarding some combinations and by discouraging others you can arrive at an organism with traits that are predictably more desirable than those of their ancestors.

In genetic engineering you are forcibly inserting genes into the procreation process to create a new organism. These genes may be from an animal of the same species, a different animal/plant, or (in theory) genes can be designed from scratch. The main difference is that with genetic engineering you can potentially arrive at a result much more quickly than with selective breeding, and you can create new organisms that would be virtually impossible to achieve through selective breeding. . Disease could be prevented by detecting people/plants/animals that are genetically prone to certain hereditary diseases, and preparing for the inevitable. Also, infectious diseases can be treated by implanting genes that code for antiviral proteins specific to each antigen. 3. The main advantage is that it illuminates cross species reactions and can be produced in greater quantities. 4. Do the fact of DNA fingerprinting that can be used to identify each individual.

