Questions
An Hfr strain that is met + pro + bio + his + was mated with an F- strain that was met - pro - bio - his -.
An Hfr strain that is met + pro + bio + his + was mated with an F- strain that was met - pro - bio - his -. Mating was interrupted and the percentage of cells with each phenotype was determined by replica plating the cells on minimal media plates that lacked met, pro, bio or his. The data shown in Figure 1 were obtained. (Figure 1)
Using the data in Figure 1, label each line on the results graph below.
Drag the phenotype to the appropriate line on the graph.
In: Biology
Generally speaking, which of the following mutations would most severely affect the protein coded for by a gene?
Generally speaking, which of the following mutations would most severely affect the protein coded for by a gene?
- a base substitution at the beginning of the gene
- a base substitution at the end of the gene
- a frameshift deletion at the beginning of the gene
- a frameshift deletion at the end of the gene
In: Biology
Label the four mutated DNA segments shown below according to the type of point mutation each represents.
Label the four mutated DNA segments shown below according to the type of point mutation each represents. Use the codon table above to determine how each mutation would affect the amino acid coding for each segment.
Drag the labels to their appropriate locations to identify the type of point mutation shown.
In: Biology
If a segment of DNA were replicated without any errors, the replicated strand would have the following sequence of nucleotides:
5' - ACTACGTGA - 3'
Sort the following replicated DNA sequences by the type of point mutation each contains (frameshift, base substitution, or neither), as compared to the correct sequence shown above.
Sort the items into the appropriate name as frameshift mutation, base substitution mutation and or neither
5'-ACTCGTGA-3'
5'-ATTACGTGA-3'
5'-ACTACGTGT-3'
5'-ACTAAGTGA-3'
In: Biology
Drag each label into the appropriate bin depending on whether it applies to primary, secondary, tertiary, or quaternary structure
Drag each label into the appropriate bin depending on whether it applies to primary, secondary, tertiary, or quaternary structure
In: Biology
The DNA in a cell's nucleus encodes proteins that are eventually targeted to every membrane and compartment in the cell, as well as proteins that are targeted for secretion from the cell.
For example, consider these two proteins:
1. Phosphofructokinase (PFK) is an enzyme that functions in the cytoplasm during
glycolysis.
2. Insulin, a protein that regulates blood sugar levels, is secreted from specialized
pancreatic cells.
Assume that you can track the cellular locations of these two proteins from the time that translation is complete until the proteins reach their final destinations.
For each protein, identify its targeting pathway: the sequence of cellular locations in which the protein is found from when translation is complete until it reaches its final (functional) destination. (Note that if an organelle is listed in a pathway, the location implied is inside the organelle, not in the membrane that surrounds the organelle.)
Options:
Cytoplasm only, ER --> cytoplasm, ER --> Golgi --> outside cell, cytoplasm --> ER --> outside cell, Golgi --> ER --> outside cell, cytoplasm --> Golgi --> outside cell, nucleus --> cytoplasm, ER --> Golgi --> cytoplasm
Protein Targeting Pathway
PFK _______________
Insulin _______________
In: Biology
Based on the genetic code chart below, which of the following would be the result of this single base-pair substitution?
The diagram below shows an mRNA molecule that encodes a protein with 202 amino acids. The start and stop codons are highlighted, and a portion of the nucleotide sequence in the early part of the molecule is shown in detail. At position 35, a single base-pair substitution in the DNA has changed that would have been a uracil (U) in the mRNA to an adenine (A).
Based on the genetic code chart below, which of the following would be the result of this single base-pair substitution?
- A. a silent mutation (no change in the amino acid sequence of the protein)
- B. a frameshift mutation causing extensive change in the amino acid sequence of the protein
- C. a missense mutation causing a single amino acid change in the protein
- D. a frameshift mutation causing a single amino acid change in the protein
- E. a nonsense mutation resulting in early termination of translation
In: Biology
Ribosomes provide the scaffolding on which tRNAs interact with mRNA during translation of an mRNA sequence to a chain of amino acids.
In: Biology
A tRNA anticodon is 5' GAA 3'. Answer the following questions.
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Practice Problem 50 A tRNA anticodon is 5' GAA 3'. Answer the following questions. |
Part A Which one of the following codons is recognized by this tRNA? Which one of the following codons is recognized by this tRNA?
Part B The first base at the 5' end of the anticodon has relaxed base-pairing rules allowing some tRNAs to bind multiple codon sequences. This is called the third base "wobble" hypothesis. How many codons could a tRNA with the anticodon 5'-GAA-3' recognize?Enter your answer as a whole number.
Part C Which amino acid does this tRNA carry?
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In: Biology
Compare and contrast the properties of DNA polymerase and RNA polymerase.
Compare and contrast the properties of DNA polymerase and RNA polymerase.
Drag the appropriate items to their respective bins.
In: Biology
If all 5' and 3' splice sites were always used to process the pre-mRNA into mRNA, how many possible distinct mRNA sequences would result from this processing?
If all 5' and 3' splice sites were always used to process the pre-mRNA into mRNA, how many possible distinct mRNA sequences would result from this processing?
In: Biology
In this problem you will explore how to solve problems involving partial diploid lac operon bacterial strains.
In this problem you will explore how to solve problems involving partial diploid lac operon bacterial strains.
Bacterial strains that are "partially diploid" have two copies of the lac operon because they aquired a plasmid carrying just the lac operon region. One copy of the lac operon region is on the recipient's bacterial chromosome, and the other copy is on the P plasmid that was introduced into the cell by conjugation. Partial diploid genotypes are written with the P segment first and the recipient chromosome next.
You create a lac operon partial diploid with this genotype:
F' I+ P+ Oc Z- Y+ / I- P+ O+ Z+ Y-
To determine which genes are transcribed and under what conditions, you need to first consider each genotype separately, and then together.
Part A
For each region of the lac operon on the P plasmid, I+ P+ Oc Z- Y+, determine whether the region is wild type (that is, it produces a functional protein or it's a correct protein binding sequence) or whether the region is mutated.
- Select all that apply.
- The promoter sequence is correct/functional.
- The repressor protein is produced.
- The operator sequence is correct/functional.
- Beta-galactosidase is produced from the lacZ gene.
- Permease is produced from the lacY gene.
Part B
Use the information from Part A to determine how the operon is regulated for this genotype (I+ P+ Oc Z- Y+).
- Operon is inducible; permease is produced only in the presence of lactose.
- Operon is repressible; permease is only produced in the absence of lactose.
- Operon is constitutive; permease is produced even when lactose is absent.
- Operon is noninducible; permease is never produced, even when lactose is present.
In: Biology
For each region of the lac operon on the F' plasmid, I+ P+ Oc Z− Y+ , determine whether the region is wild type
For each region of the lac operon on the F' plasmid, I+ P+ Oc Z− Y+ , determine whether the region is wild type (that is, it produces a functional protein or it's a correct protein binding sequence) or whether the region is mutated. Select all that apply. Select all that apply. The promoter sequence is correct/functional. The repressor protein is produced. The operator sequence is correct/functional. Beta-galactosidase is produced from the lacZ gene. Permease is produced from the lacY gene.
In: Biology
Which of the following occurs as a result of an abundance of tryptophan in E. coli?
Which of the following occurs as a result of an abundance of tryptophan in E. coli?
A.The leader sequence is not transcribed.
B.The 5 trp genes (TrpA - TrpE) are not transcribed.
C.Stalling of the ribosome at trp codons in the leader sequence
D. The 5 trp genes (TrpA - TrpE) are transcribed, but not translated.
In: Biology