Chapter 16: The Molecular Basis of Inheritance
Explain the structure of DNA and nucleotides. Include a model of your explanation.
DNA is made up of a sugar-phosphate backbone (a 5 carbon sugar called Deoxyribose and a phosphate group) and a nitrogenous base (Adenine, Thymine, Guanine, Cytosine). This is then attached to another nitrogenous base (which is complementary to it) and sugar-phosphate backbone by a hydrogen bond. This creates the ladder-like rungs of the double helix.
Develop a model which explains the major steps to replication, specifically a replication bubble.
Compare and contrast the difference between replication, transcription, and translation. Replication in DNA occurs in the nucleus. It is the process of copying a double-stranded DNA molecule using a template DNA strand and DNA polymerase that produces new DNA. Transcription occurs in the nucleus and is the synthesis of mRNA from a DNA template using RNA polymerase. Translation is the synthesis of proteins from mRNA that occurs in the cytoplasm.
Develop a model and explain how DNA is packaged into a chromosome.
In plant and animal cells, DNA is packaged into structures called chromosomes. A single strand of DNA is wrapped many times around various proteins (histones), to form structures called nucleosomes. These nucleosomes coil up tightly to create chromatin loops. The chromatin loops then wrap around each other to make a full chromosome. Each chromosome has two short arms (p arms), two longer arms (q arms), and a centromere that holds it together at the center.
Chapter 17: From Gene to Protein
Compare and contrast the key terms gene expression, transcription, and translation.
Gene expression is the process by which DNA directs protein synthesis which occurs in two stages: transcription and translation. Transcription is the synthesis of RNA that occurs in the nucleus using information in DNA that produces messenger RNA (mRNA). Translation is the synthesis of a polypeptide that occurs in the cytoplasm or ribosomes using information in the mRNA.
Develop a model and explain the process of transcription and translation.
Transcription is the synthesis of RNA that occurs in the nucleus using information in DNA that produces messenger RNA (mRNA).
Translation is the synthesis of a polypeptide that occurs in the cytoplasm or ribosomes using information in the mRNA. It occurs in three stages: Initiation, Elongation and Termination.
Explain how eukaryotic cells modify RNA after transcription and why it is necessary. An example of a post-transcriptional modification is splicing. Splicing is the removal of non-coding regions (introns) of RNA in order to join the coding regions (exons). This process uses spliceosomes, which consist of a variety of proteins and several small nucleus ribonucleoproteins (snRNPs) that recognize the spice sites. Splicing is required in eukaryotes to generate mature coding RNAs out of previous RNAs still containing Introns, which need to be removed to produce the correct protein.
Develop a model which explains how point and frameshift mutations can impact a protein.