BIOCHEM 2EE3 Lecture Notes - Lecture 6: Nucleophile, Start Codon, Amine

25 views5 pages

peachmammoth673

21 Mar 2018

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Protein synthesis basics- how proteins work in transcription and translation. Transcription: dna (genetic information) is transcribe to rna, which is translated to protein bacterial transcription, 3 phases: phase 1: initiation. Phase 3: termination: key protein player in transcription is rna polymerase, rna designation tells us that the product will be rna based not dna-based, the dna sequence itself encodes for a number of key elements: Initial element to direct rna polymerase binding to the dna at the start of the sequence. The sequence of the gene itself: one gen encodes for one protein. Termination element that direct rna polymerase to stop transcribing the dna. Rna polymerase: structure function: rna polymerase is a holoenzyme containing 5 subunits ((cid:573), (cid:574), (cid:574)(cid:495), and ) 1 (cid:573) (cid:523)alpha(cid:524) (cid:574) (cid:523)beta(cid:524) (cid:574)" (cid:523)beta prime(cid:524) Chain initiation, interaction with regulatory protein and upstream promoter elements. This strand is not used by the rnap as the template for transcription for rna polymerase.

Related Questions

Which type of RNA is unique to eukaryotes?

		mRNA
		rRNA
		tRNA
		snRNA
		Its a trick, all cells have all four types of RNA.

1 points

QUESTION 2

The region of DNA to which RNA polymerase binds to initiate transcription is the:

		origin
		promoter
		enhancer
		none of the above are correct

1 points

QUESTION 3

Holoenzyme:

		is RNA polymerase core enzyme.
		is sigma factor.
		is core plus sigma factor.
		none of the above are correct.

1 points

QUESTION 4

Which of these is formed FIRST when RNA polymerase binds to a promoter?

		The closed promoter complex
		The open promoter complex
		A rho-independent terminator
		none of the above are correct.

1 points

QUESTION 5

A hairpin loop followed by a run of Us:

		is the sequence formed in the sense strand of a gene using a rho-independent terminator.
		is the sequence recognized by the rho protein.
		is the structure formed in RNA that causes rho-independent termination.
		is formed immediately after the open promoter complex is formed.

1 points

QUESTION 6

RNA polymerase:

		reads the template strand of the DNA in the 3' to 5' direction.
		synthesizes the RNA in the 5' to 3' direction.
		can begin transcription without a primer.
		all of the above are correct.

1 points

QUESTION 7

Which of the following statements is FALSE?

		Bacteria like E. coli have only one type of sigma factor.
		RNA polymerase has no proofreading activity.
		The promoter of a gene is upstream of the RNA-coding region.
		Bacterial transcriptional terminators are copied into RNA to cause termination.

1 points

QUESTION 8

If the template strand of a gene has the sequence 5' ATGCGAT 3', then:

		the RNA produced will have the sequence 5' AUGCGAU 3'.
		the RNA produced will have the sequence 5' UAGCGUA 3'.
		the RNA produced will have the sequence 5' AUCGCAU 3'.
		None of the above are correct.

1 points

QUESTION 9

The sense strand:

		is the lagging strand
		is also the template strand.
		always goes left to right.
		none of the above are correct.

1 points

QUESTION 10

Which of these is transcribed but not translated?

		mRNA
		tRNA
		rRNA
		all of the above
		tRNA and rRNA are transcribed but not translated.

please help i am a bit confused

5. Alpha amanitin is a drug that binds RNA polymerase andprevents it from functioning in the cell (this is the compound thatis found in poison mushrooms). The reason people die when theyconsume alpha amanitin is:

a) Alpha amanitin prevents gene expression from occurring in thecell

b) DNA replication is directly inhibited by alpha amantin

c) Alpha amanitin binds tightly to the messenger RNAs that aremade in the cell, preventing translation

d) Alpha amanitin binds to nuclear pores preventing thetransport of messenger RNA into the cytoplasm

6. In order for transcriptional initiation to begin in E. colithe following elements are needed:

a) an origin and RNA polymerase

b) initiator protein and a promoter

c) the sigma subunit of RNA polymerase and an RNA template

d) RNA polymerase and a promoter

e) helicase and primase

Questions 7 and 8. You are studying two species of closelyrelated snakes, one species lives in sandy desert area and has paletan skin and the species lives in a volcanic rock area and has darkbrown skin. You a sequence the DNA from each type of snake anddiscover a gene encoding a protein that transports pigment into theskin cells. The pigment transporter protein is responsible for skincolor. When you analyze the DNA coding sequence of the pigmenttransporter from each snake you find these two DNA sequences (hashmarks have been added to indicate the reading frame):

pale tan snake: GCG/TTG/GAC/TGC/ACC (DNA template strand)CGC/AAC/CTG/ACG/TGG (complementary strand) dark brown snake:ACG/TTG/GAC/TGC/ACC (DNA template strand) TGC/AAC/CTG/ACG/TGG(complementary strand)

7. From these sequences you conclude:

a) that the amino acid sequence of the pigment transporters forthe two proteins are almost identical

b) that the amino acid sequence of the pigment transporters forthe two proteins are very dissimilar

c) that the amino acid sequence of the pigment transporters forthe two proteins are identical

8. Since the skin color is different in each snake, you concludefrom the sequence data above that:

a) the genetic code in the skin cells in each of these snakes isdifferent

b) the DNA sequence encoding the entire gene for pigmenttransporters in these two snakes is different

c) that one of the codons in the gene for the pigmenttransporter in these two snakes is different

9. You are analyzing eukaryotic cells that have been exposed tothe radioactive uracil. In most cells the radioactive uracil isinitially localized in the nucleus and then moves from the nucleusto the cytoplasm. However, you observe that in some cells theradioactive molecules stay in the nucleus and never arrive in thecytoplasm. This is most likely a defect in:

a) the transcription of the DNA

b) the processing of the mRNA

c) the translation of the RNA

d) the labeling of the RNA

e) the replication of the DNA

10. Which of the following is true of both eukaryotic andbacterial transcription? (select all that are true)
a) Transcription factors must bind the promoter before RNApolymerase initiates transcription

b) Messenger RNAs must be spliced before translation begins inorder to produce the appropriate gene product

c) During transcription only one DNA strand is used as atemplate to make the messenger RNA

d) Termination of transcription occurs when the RNA polymerasetranscribes a hairpin structure in the RNA followed by a string ofU

erinporpoise384

Which of the two major categories of the chemical reactions in photosynthesis is oxygen the INDIRECT product?

Glycolysis

Oxidative phosphorylation

Both light and dark

Light independent phase (LIP)

Light dependent phase (LDP)

You have a stomach flu characterized by vomiting. Which of the following systems is most responsible for the food in your stomach going the wrong way, e.g. vomiting? (Disregard this question and answer choice B)

Cardiac Muscle in the large intestine as discussed in class.

Smooth muscle in the gastrointestinal tract

Smooth muscle in the blood vessels

Skeletal muscle in the intestine

Proteins are made from which of the following smaller sub units?

Nucleotides

Amino acids that cannot enter the blood stream and go to cells

Monosaccharides

Fatty acids

Amino acids which can form new protein

Carbohydrates are digested in the gastrointestinal system into which of the following substances that is the smallest structure?

Polysaccharides that are produced by glucagon

Monosaccharides that are produced by insulin

Monosaccharides

Polysaccharide

Which of the following biomolecules has the longest digestion time? In other words, how long does it take for the biomolecule to be catabolized?

DNA

Lipid

Carbohydrate

Protein

You are sunburned after a long day at the beach. Which one is not an example of UV damage to your skin cells?

A mutation can occur in your ovaries

A mutation can occur in skin cell DNA that can lead to errors in transcription.

Errors can occur during DNA replication.

UV light can cause mutations in DNA of skins cells.

Thymine bases in your skin DNA bond with each other instead of across the double helix

This region, the ______________ (a) tells RNA polymerase where to bind to DNA while this region, the ______________ (b) tells RNA where to start transcription.

(a) promoter, (b) open reading frame

(a) start codon, (b) methionine

(a) promoter, (b) start site

(a) start site, (b) promoter

The genetic code is used to translate ______________ into ______________.

lipids, nucleotides

nucleotides,carbohydrates

nucleotides, lipids

nucleotides, amino acids

nucleosides, amino acids

Transcription of a gene has just completed. What are the next steps (in the correct order) to complete expression of that gene?

RNA polymerase makes a copy of DNA into mRNA.

mRNA is translated in the nucleus and ribosomal RNA moves into the cytoplasm.

Gene expression is completed after transcription.

mRNA moves into the cytoplasm and with tRNA they interact to form protein

Translation machinery moves into the nucleus and mRNA is translated into protein.

How is it that a mutation in DNA stored inside the nucleus of a cell can cause a disease affecting multiple organs?

This remains an unanswered question in science that scientists are still trying to figure out.

The mutated DNA is expressed in multiple cells through the process of transcription and translation, and the altered protein causes the disease wherever the DNA was expressed.

The mutated DNA is expressed in one cell and the altered protein travels to multiple organs to cause disease.

The mutated DNA is expressed and the mRNA takes the mutated information to other cells where the altered protein is made to cause disease in that organ.

The advantage of sickle cell anemia is which of the following?

It decreases the amount of oxygen in the blood cells so that mosquitoes carrying malaria will live

It decreases the amount of oxygen in the blood cells so that mosquitoe's blood form will die.

It allows the blood vessels to decrease the amount of blood going to the toes and feet.

There is none.

Which of the following is a purpose of cell division?

Cell reproduction

Growth

Repair

All of these

BIOCHEM 2EE3 Lecture Notes - Lecture 6: Nucleophile, Start Codon, Amine

Document Summary

Get access

Related Documents

BIOCHEM 2EE3 Lecture 5: Biochem Module 5 - TRANSLATION AND TRANSRIPTION

BIOCHEM 2EE3 Lecture Notes - Lecture 6: Amine, Prokaryotic Large Ribosomal Subunit, Adenine

BIOCHEM 2EE3 Lecture Notes - Lecture 6: World Federation Of Trade Unions, Intron, Thermodynamic Cycle

Related Questions