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Bio 250 - Exam Two Assessment with
Exact and certified Answers.
frameshift mutation - Correct Ans: ✔✔when an extra base is added to a DNA sequence, which can change the amino acid sequence and cause extra bases without amino acids.
silent mutation - Correct Ans: ✔✔when the base sequence changes but doesn't cause a change in the amino acid, for example CCA and CCC both code for glycine.
nonsense mutation - Correct Ans: ✔✔when the change in a base sequence causes a stop codon rather than an amino acid.
missense mutation - Correct Ans: ✔✔when the change in a base sequence causes one amino acid to change into a different one.
what might occur if lysosomes were not membrane bound? - Correct
Ans: ✔✔the enzymes within the lysosome could easily get out and affect the other organelles within the cell, and possibly destroy things that aren't supposed to be or don't need to be destroyed.
what might occur if the nucleus was not membrane bound? -
Correct Ans: ✔✔The DNA might not be protected as well if any type of protein or other organelle is able to enter the nucleus.
what might occur if the mitochondria was not membrane bound? -
Correct Ans: ✔✔the adenosine triphosphate (ATP) within the mitochondria could leave that organelle and be used for other energy purposes within the cell.
what might occur if the ER was not membrane bound? - Correct
Ans: ✔✔proteins could easily attach and detach from the ER and would make the job of protein translocators much simpler.
what might occur if the golgi apparatus was not membrane bound? -
Correct Ans: ✔✔proteins would much easilier be able to enter and leave the golgi to be sorted and then also it would be easier for the lysosome to take to proteins to their next destination.
You have isolated an organelle from a human cell and identified the following macromolecules: 18S rRNA and signal peptidase. What
organelle did you isolate? - Correct Ans: ✔✔The organelle isolated was the rough ER because 18s rRNA is found in ribosomes and ribosomes can be located along the ER, where signal peptidase can also be identified within the ER.
Which of the following choices reflects the appropriate order of locations through which a protein destined for the plasma
membrane travels? - Correct Ans: ✔✔(d) ER -> Golgi -> plasma membrane
What chronological sequence of events occurs in the Central Dogma
of Life? - Correct Ans: ✔✔DNA - RNA - protein
- transport across membrane
How are DNA and RNA different? - Correct Ans: ✔✔In RNA one of the bases is uracil and in DNA that base is thymine.The sugar present in RNA structure is ribose and in DNA in deoxyribose. There are different types of RNA that perform different function ie. mRNA, tRNA and rRNA.
How are DNA and RNA similar - Correct Ans: ✔✔both form hydrogen bonds. Both of them are nucleotides. They bothinclude a phosphate backbone in their structure.
What will be the RNA sequence for the following DNA if the top strand is the template strand?
5' - AGGTCCACTGGGC - 3'
3' - TCCAGGTGACCCG - 5' - Correct Ans: ✔✔3' UCCAGGUGACCCG 5'
How is the process of transcription in eukaryotes similar to
prokaryotes? - Correct Ans: ✔✔Both prokaryotes and eukaryotes have the same three steps for transcription; initiation, elongation, and termination.
How is the process of transcription in eukaryotes different from
prokaryotes? - Correct Ans: ✔✔Eukaryotes have a CTD tail which when phosphorylated causes a pause between the initiation and elongation steps of transcription.
This phosphorylation of the CTD tail is needed for the transcription to continue in eukaryotes, while prokaryotes have a sigma factor that's removed to continue transcription.
where are these located?
ribosome-binding site
initiator codon
stop codon
untranslated 3′ region
untranslated 5′ region
protein-coding region - Correct Ans: ✔✔
What RNA sequence will be made from the following template DNA sequence?
5' - ATGCCAGGATACCGAGC - 3' - Correct Ans: ✔✔3' UACGGUCCUAUGGCUCG 5'
In complete sentences explain how DNA replication and transcription
are different. - Correct Ans: ✔✔When DNA replicates the strand splits in two, creating two new strands that each have half of the original strand along with half of a new strand. DNA transcription is the process of a strand of DNA being translated into RNA, including the change of thymine to uracil.
Explain three ways that the process of eukaryotic transcription is
different from the process of prokaryotic transcription. - Correct
a. Nucleus
b. Endoplasmic reticulum
c. Cytosol
d. Outer cell membrane - Correct Ans: ✔✔cytosol
A protein has one SSS at the N-terminus that directs it to the nucleus. Where will the protein be localized if there is a nonsense mutation in the middle of this protein?
a. Nucleus
b. Endoplasmic reticulum
c. Cytosol
d. Outer cell membrane - Correct Ans: ✔✔nucleus
substitution mutation - Correct Ans: ✔✔when one base changes into a different one, for example an A changing to a G.
Plasma membrane proteins are inserted into the membrane in the __________________. The address information for protein sorting in a eukaryotic cell is contained in the __________________ of the proteins. Proteins enter the nucleus in their __________________ form. Proteins that remain in the cytosol do not contain a __________________. Proteins are transported into the Golgi apparatus via __________________. The proteins transported into the endoplasmic reticulum by __________________ are in their __________________ form.
amino acid sequence. Golgi apparatus sorting signal
endoplasmic reticulum. plasma membrane transport vesicles
folded protein translocators unfolded - Correct Ans: ✔✔Plasma membrane proteins are inserted into the membrane in the __endoplasmicreticulum____. The address information for protein sorting in a eukaryotic cell iscontained in the amino acid sequence of the proteins.· Proteins enter the nucleus in their _____folded____ form.· Proteins that remain in the cytosol do not contain a sorting signal____.· Proteins are transported into the Golgi apparatus via transport vesicles.· The proteins transported into the endoplasmic reticulum by protein translocators_are in their unfolded form.
