DNA replication
What is DNA replication? What is its purpose?
Copying of genetic molecules for the next cells and generations
What is transcription in the context of molecular biology?
Making RNA from DNA
What is translation in the context of molecular biology?
The process of reading information from an RNA molecule and converting it into a protein
What is the importance of regulating gene expression?
To respond to environmental stimuli/external factors
How many base variations are there for the Start and Stop codons?
Four. One for the Start (AUG) and 3 for the Stop codons (UAA, UAG, UGA).
This enzyme is responsible for unwinding the DNA double helix.
Helicase
Describe the 3 key differences between RNA and DNA
1) Ribose vs deoxyribose backbone
2) Uracil vs thymine
3) Single strand vs double stranded
Describe the two types of protein secondary structures
Alpha helix and beta sheets
Transcription, translation, and post-translation
What is the length of an RNA (in bases) that code for 9 amino acids?
9 x 3 = 27 RNA bases
This enzyme synthesizes the RNA primer.
Primase
Why does RNA have more structural variations compared to DNA?
Single-stranded, can fold into different configurations
How many different types of (core) RNA are there? Name all of them.
Ribosomal RNA, messenger RNA, transfer RNA
Give an example of gene regulation at the translation (RNA->protein) level
Modify mRNA structure and stability
Here is an RNA sequence: 5'-AUG GCU AAA UUU GGC UAG-3'
What is the corresponding amino acid sequence?
Met-Ala-Lys-Phe-Gly-Stop
This enzyme adds nucleotides to the growing DNA strand in the 5' to 3' direction.
DNA polymerase
What is the length of a typical 16S ribosomal RNA?
1600 base pairs
Name 2 types of bonds in protein building. Which one is stronger than the other?
Hydrogen and disulfide bond. Disulfide bonds are stronger
After a protein is formed, a regulation step occurs in which the cysteine amino acids and its sulfide bonds are blocked. Would this lead to increased or decreased stability of the protein?
Decreased
How many different mutation types are there? Explain each of them.
Four: Silent, missense, nonsense, readthrough
DNA ligase
Describe the idea for the RNA World Hypothesis for the origin of life
RNA can simultaneously be the genetic material and workhorse (protein-like)
What is the typical number of genes present in a prokaryotic cell?
3000 genes
A cell is suddenly exposed to large quantities of glucose, and it now needs to make the enzymes to utilize this nutrient. Describe how the gene expression is regulated, step-by-step.
Glucose or its related products bind to activators, which bind upstream of the gene. Or, they bind to repressors and move the repressors.
Here are 3 RNA sequences:
1) 5'-AUG GGC UAA UUU UGA-3'
2) 5'-AUG GCU AUG UUU UGA-3'
3) 5'-AUG CCG UUU AGA GCA UGA-3'
Which of these code for a functional protein?
1) Met-Gly-Stop-Phe-Stop
2) Met-Ala-Met-Phe-Stop
3) Met-Pro-Phe-Arg-Ala-Stop