chapter 11, 12, 13 Copyright © The McGraw-Hill Companies, Inc.. DNA Biology and
ID: 167231 • Letter: C
Question
chapter 11, 12, 13
Copyright © The McGraw-Hill Companies, Inc..
DNA Biology and Gene Regulation
1. Understand and explain DNA Replication and its semiconservative model.
2. Compare and contrast the structure of RNA with that of DNA.
3. List the three major types of RNA and describe their functions.
4. List the steps involved in gene expression and describe the part of the cell in which each step occurs: transcription and translation.
5. Explain what the genetic code is used for and explain why it is considered to be almost universal.
6. Describe how transcription copies the information from a gene into a messenger RNA molecule.
7. Describe how the process of translation converts the chemical language of nucleic acids into a protein and list the three phases of this process.
8. Explain the most common effects of mutations and the changes they induce.
9. Understand applications of the DNA technology.
10.Summarize the operation of the lac operon in prokaryotes.
11.List the level of control of gene expression in eukaryotes.
12.Distinguish between proto-oncogenes and tumor suppressor genes in regard to cancer.
Explanation / Answer
1. The replication of a DNA molecule begins when the two complementary DNA strands are separated. This is usually accomplished by special proteins that unwind the molecule and expose the nucleotide bases.New complimentary DNA strands are then synthesised by joining together deoxyribonucleotide triphosphates, one at a time, and with the removal of a diphosphate.The bases pair up as the new DNA strand is synthesised. At the end of the process the cell has made to identical copies of all the biological information contained in the original, parental, DNA molecule, but the two new daughter DNA molecules are "Half old" and "Half new". Half the original DNA molecule is saved or conserved in the daughter molecules. This is why the process is called semi-conservative.
2.
3.
4.Gene expression is the process by which the genetic code - the nucleotide sequence - of a gene is used to direct protein synthesis and produce the structures of the cell. Genes that code for amino acid sequences are known as 'structural genes'.
The process of gene expression involves two main stages:
Transcription: the production of messenger RNA (mRNA) by the enzyme RNA polymerase, and the processing of the resulting mRNA molecule.
Translation: the use of mRNA to direct protein synthesis, and the subsequent post-translational processing of the protein molecule.
Some genes are responsible for the production of other forms of RNA that play a role in translation, including transfer RNA (tRNA) and ribosomal RNA (rRNA).
DNA RNA Sugar Deoxyribose Ribose Bases Adenine, guanine, thymine , cytosin Adenine, guanine, uracil , cytosin Strands Double stranded with base pairing Single stranded Helix Yes NoRelated Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.