All High School Biology Resources
Example Questions
Example Question #2 : Understanding Transcription Processes
Which of the following processes creates messenger RNA from a DNA?
Replication
Translation
Transcription
Respiration
Transcription
The process of forming messenger RNA from a strand of DNA is called transcription. Replication is the creation of new DNA from the original DNA strands. Translation is the creation of a protein chain from the messenger RNA strand using transfer RNA.
Example Question #3 : Rna
All of the following statements about RNA are true EXCEPT __________.
adenine always pairs with uracil and cytosine always pairs with guanine in RNA
adenine always pairs with thymine and cytosine always pairs with guanine in RNA
RNA contains the carbohydrate ribose
RNA is most frequently a single-stranded molecule
RNA and DNA both have a sugar-phosphate backbone in their molecular structure
adenine always pairs with thymine and cytosine always pairs with guanine in RNA
It is important to remember the base-pairing rules when discussing both DNA and RNA because they are the rules by which all of transcription and translation occur. In RNA, uracil takes the place of thymine, creating an A-D pair instead of an A-T pair. The structure of RNA is a single strand of alternating ribose and phosphate groups with nitrogenous bases attached to the ribose. One way that DNA and RNA differ is that DNA contains deoxyribose sugar while RNA contains the ribose sugar.
Example Question #1 : Rna
Protein synthesis is the process by which proteins are made in cells. The proper order and location of the two main parts of protein synthesis are __________.
1) Translation in the nucleus 2) Transcription in the endoplasmic reticulum
1) Translation at the ribosome 2) Transcription in the nucleus
1) Transcription in the nucleus 2) Translation at the ribosome
1) Transcription at the ribosome 2)Translation in the nucleus
1) Transcription in the cytoplasm 2) Translation in the nucleus
1) Transcription in the nucleus 2) Translation at the ribosome
Transcription must occur first because it is the process that copies the genetic code from the DNA, and it must occur in the nucleus because DNA is too large a molecule to leave the nucleus. Next comes translation, which is the reading of the "photocopied" code (mRNA) after it leaves the nucleus and connects with a ribosome. After this, the mRNA binds with ribosomes and is translated to create proteins.
Example Question #11 : Transcription
The tRNA holds the _________ which is the complimentary code of the __________ on the mRNA.
protein . . . amino acid
transcription . . . translation
anticodon . . . codon
polypeptide . . . nucleic acid
codon . . . anticodon
anticodon . . . codon
RNA is the key molecule involved in protein synthesis. During translation, the mRNA binds to a ribosome carrying a sequence of codons. The tRNA then binds to the ribosome/mRNA complex with the matching anticodon. The anticodon contains the three complimentary nucleotides to the codon.
Example Question #431 : High School Biology
Prokaryotic transcription __________.
involves tRNA
occurs in the nucleus
is the same as eukaryotic transcription
occurs on ribosomes
occurs in the cytoplasm
occurs in the cytoplasm
Prokaryotes do not have nuclei. It is translation, not transcription, that occurs on ribosomes. tRNA is the type of RNA that brings amino acids to the ribosome; again, translation is the process of protein synthesis from amino acids. There are many differences between eukaryotic and prokaryotic transcription! These differences are monumental in differentiating between eukaryotes and prokaryoes. For example, in eukaryotes, transcription occurs in the nucleus and involves mRNA processing—adding a 5' cap, adding a 3' poly-A tail, and splicing out introns; none of these things are true for prokaryotes.
Example Question #13 : Transcription
mRNA gets translated by the ribosome in sets of __________ nucleotides.
two
four
six
three
one
three
The genetic code is based on codons, which are sets of three nucleotides. mRNA is read in the triplet code; each codon specifies for an amino acid. The genetic code is redundant (one amino acid may be coded for by multiple codons), but each codon only codes for one amino acid, or the stop codon.
Example Question #14 : Transcription
Which of these processes does not play a role in transcription regulation?
Chromatin remodeling complexes
Repressors
DNA binding motifs and the associated proteins
Ubiquitin
Alternative splicing
Ubiquitin
Ubuiqitin is a protein synthesized to tag worn out or defective proteins for recycling. Since this would only eliminate proteins that have already been synthesized, it would be more of a translational regulation process.
The other choices are common transcription regulators. Chromatin remodeling complexes are proteins that interact with the histones in chromatin. They are able to expand or condense the amount of coiling around histones and therefore allow greater or lesser access by transcription machinery to the DNA; thus, when the DNA is more tightly bound, it is less accessible and transcription is regulated. Our genes are broken into coding and non-coding sequences called exons and introns respectively. Alternative splicing is a process that alters the mRNA transcription product by selecting different combinations of exons to be joined together. This is an important process and allows the body to produce many more proteins than it normally would from the same quantity of genes. DNA binding motifs and their associated proteins are called transcription factors when interacting and they regulate transcription. They regulate by blocking a genes' promoter region (reduces the expression of that sequence) or they bond to the promoter to help the transcription machinery recognize that sequence and assemble itself (increases expression). Last, repressor proteins bond to promoter regions of genes they regulate. Often times the product of that gene is responsible for activating and inactivating that repressor. For example, a large quantity of a gene product can make it more likely for the repressor and that gene product (protein) to meet and join. This activity generally turns repressors on and transcription of that gene is reduced or stopped.
Example Question #14 : Transcription
Which of the following types of RNA forms ribosomes?
rRNA
tRNA
miRNA
mRNA
snRNA
rRNA
rRNA forms ribosomes.
tRNA is transport RNA, it joins amino acids to ribosomes to assemble a protein molecule
SnRNA is small nuclear RNA, it splices pre-mRNA to form mRNA
miRNA is microRNA, which regulates gene transcription and translation
mRNA is messenger RNA, carries the genetic code for controlling the protein formed.
Example Question #1 : Understanding Rna Backbone
What is the difference in the structure of the sugars used in RNA and DNA?
The sugar in RNA has a hydroxyl on the 3' carbon, while DNA does not
The sugar in DNA has a hydroxyl on the 2' carbon, while RNA does not
The sugar in DNA has a hydroxyl on the 3' carbon, while RNA does not
The sugar in RNA has a hydroxyl group on the 2' carbon, while DNA does not
The sugar in RNA has a hydroxyl group on the 2' carbon, while DNA does not
The full names of the sugars used in nucleic acid structures are ribose (for RNA) and deoxyribose (for DNA). Both sugars have five carbon atoms arranged in a ring. In ribose, the carbon in the 2' position is bound to a hydroxyl group (-OH). In deoxyribose, however, the 2' carbon is bound to a simple hydrogen atom.
Example Question #12 : Rna
DNA and RNA have similar structures but some differences, and are used for different functions within the cell.
The backbone of RNA is different from the backbone of DNA due to the presence of __________.
phosphodiester bonds
hydrogen bonds
ribose structure
uracil
peptide bonds
ribose structure
DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) have backbones that are identical, except that the five-carbon sugar in RNA (ribose) has one oxygen that the sugar in DNA (deoxyribose) lacks.
Hydrogen bonding is no different between the two molecules, and primarily serves to bind nitrogenous bases rather than regions of the backbone.
Peptide bonds are not formed in DNA or RNA. Rather, these bonds are used to connect the amino acid monomers in a protein molecule.
Uracil is found in RNA and not in DNA, but does not impact the backbone.
Phosphodiester bonds are used to bind adjacent nucleotides together in both DNA and RNA.