Biology

Chapter 10 Assignment – The Structure and Function of DNA Name:Fabio R Bravo
1. A cell containing a single chromosome is placed in a medium containing radioactive phosphate, making any new DNA strands formed by DNA replication radioactive. The cell replicates its DNA and divides. Then the daughter cells (still in the radioactive medium) replicate their DNA and divide, resulting in four cells. Sketch the DNA molecules in all four cells, showing a normal (nonradioactive DNA strand as a solid line and a radioactive DNA strand as a dashed line) (4 pts).

2. Explain how and organism’s genotype determines its phenotype (2 pts).

A: By transcribing the codes, which is very unique. The phenotype, the organism’s physical traits, arises from the actions of a wide variety of proteins. Finally the DNA specifies the synthesis of proteins.

3. What is this molecule? Label the following parts of the molecule: pentose, phosphate group, nitrogenous base (1 pts). A: The yellow circle is a Phosphate group, the right side of the blue figure are sugars (deoxyribose), on the lower part of the green figure we have Thymine (T) and above Nitrogenous base (can be A, G, C, or T). The Nucleotide is the overall picture.
4. Describe the process of transcription. Include the following terms in your description: RNA polymerase, initiation, elongation, and termination (4 pts).
A: A RNA polymerase attaches at a specific region of DNA called the promoter, and begins transcription. RNA (a type of nucleic acid consisting of nucleotide monomers, with a rise sugar, a phosphate group, and the nitrogenous base adenine, cytosine, guanine and uracil. Polymerase (A technique used to obtain many copies of a DNA molecule or many copies of part of a DNA molecule.) Initiation (The start transcribing signal is a nucleotide sequence called a promoter, which is located in the DNA at the beginning of the gene. Elongation (RNA grows longer. The RNA strand peels away from its