Microbiology LearnSmart #6 (CH8)
Order the steps in excision repair.
1. Enzymes recognize a mismatch in the two DNA strands 2. Enzymes remove the nitrogenous base on one strand 3. DNA polymerase I synthesizes new DNA as needed 4. Ligase seals the phosphate backbone of the DNA
Order the following event in the processing of eukaryotic transcripts.
1. The genes is transcribed to mRNA 2. A series of adenosines is added to the mRNA 3. A spliceosome excises intron from the mRNA 4. The mRNA leaves the nucleus 5. The mRNA is translated into a protein
Which of the following are methods of gene transfer in bacteria?
conjugation, transformation, translation
In the bacterium Escherichia coli, where is the chromosome located?
cytoplasm
According to the rules of complementary base pairing, the nitrogenous base ___ forms hydrogen bonds with guanine.
cytosine
A ___ mutation results form an insertion or deletion of nucleotides, and always leads to an change in the "reading" of codons in mRNA.
frameshift
A ____ is a sequence of DNA nucleotides that codes for a group of related proteins.
gene
____ is the study of the inheritance of living things.
genetics
What term represents ALL of the genetic information within a cell?
genome
The ____ is the genetic makeup of an organism that is ultimately responsible for an organism's expressed characteristics.
genotype
_____ breaks the hydrogen bonds holding the two strands of DNA together, resulting in two separate strands
helicase
Select the enzymes that function in DNA replication.
helicase, ligase, DNA polymerase
Match the definition of horizontal and vertical gene transfer.
horizontal-transfer of DNA from a source other than the parent organisms vertical-transfer of DNA from parent organisms during reproduction
Order these organisms by the size of their genomes, smallest to largest.
viruses, bacteria, fungi, humans
Photoactivation to repair DNA requires?
visible light, DNA photolase
Which of the following are the three major types of RNA?
transfer, ribosomal, messenger
Which types of horizontal gene transfer do NOT require direct contact between the donor and the recipient cells?
transformation, transduction
During what process is mRNA converted into a protein
translation
Which sequence of DNA nucleotides is complementary to the DNA triplet 5'-ATG-3'?
3'-TAC-5'
A ___ mutation occurs when a gene that has undergone mutation reverses back to its original sequence.
Back
Genomes are composed of?
DNA
Which two enzymes are responsible for proofreading newly replicated DNA?
DNA polymerase III, DNA polymerase I
Cellular genomes are composed of ___ whereas viral genomes may be either DNA or ___.
DNA; RNA
RNA polymerase converts ____ into various types of ___.
DNA; RNA
In eukaryotic genes, introns are interspersed between coding regions called____, that will be translated into proteins.
Exons
Eukaryotic chromosomes are composed of DNA and RNA.
FALSE
An ___ is the specific sequence of 3 mRNA nucleotides that encodes a particular amino acid.
codon
Eukaryotic mRNA contains ___ which are noncoding regions that must be removed before translation occurs.
Introns
A ___ mutation involves any subsitiution of a single nucleotide that does not change the DNA reading frame.
Point
In the central theme of molecular biology, DNA encodes _____, which encodes protein.
RNA
How does DNA and RNA differ in bacteria and eukaryotes?
RNA is single stranded, in RNA uracil replaces thymine
A spliceosome is composed of?
RNA, protein
During transcription, RNA polymerase synthesizes ____ from an ___ template.
RNA; DNA
A ___ mutation alters the DNA sequence of a gene, but does NOT change the amino acid sequence of the protein that is encoded by the gene.
Silent
A bacterial cell described as ____ can accept aoluble DNA from surrounding environment.
competent
Which is the main event of translation termination?
a stop codon is reached and the peptide is released from the ribosome
Mutation can provide adaptive advantages for cells, such as?
acquired drug resistance
Which of the following nitrogenous bases are found in both DNA and RNA?
adenine
In DNA, the two strands of the helix are arranged in an ____ arrangement.
antiparallel
What events initiate translation?
assembly of ribosomal subunits, ribosome scans to find AUG on the mRNA transcript
Transposons are linked to which of the following bacteria?
intermicrobial transfer of drug resistance, replacement of damaged DNA, Phenotypic changes in colonies.
A sequence of DNA in a eukaryotic gene that does not code for protein is called an ___.
intron
Which of the following describe the origin of replication?
located on the chromosome, AT-rich
____ is a copy of the DNA template corresponding to a protein-encoding gene.
mRNA
An ___ is a permanent inheritable alteration in the DNA sequence of a cell.
mutation
Chromosomes are located in the ___ of protozoal and fungal cells.
nucleus
The expressed characteristics resulting from the interaction of the particular genetic makeup of an organism and the environment is the ___ of that organism.
phenotype
What are the 3 components of a DNA nucleotide?
phosphate, deoxyribose, nitrogenous base
which organic molecule is formed from chains of amino acids that are produced in translation?
protein
____ are formed from long chains of amino acids produced in translation
proteins
Which term refers to the transfer of genes from donor to recipient microorganisms?
recombination
DNA ___ must occur prior to cell division to ensure that each cell has a complete set of DNA chromosomes
replication
what is commonly shared between bacteria through the process of conjugation?
resistance plasmids, genes for virulence factors
rRNA composes ____ subunits together with protein.
ribosome
What is the function of mRNA?
serves as a transcript of a gene sequence of template DNA
Which type of mutations are caused by random errors in DNA replication?
spontaneous
The mRNA sequence AUG, specifying the first amino acid in protein sequences, is called the ____ codon.
start
___ genes code for proteins.
structural
Which of the following are differences between eukaryotic and bacterial protein synthesis?
the first amino acid is slightly different; transcription and translation are simultaneous in bacteria but not eukaryotes
Which are events of translation elongation?
the ribosome shifts from one codon on the mRNA to the next, a tRNA delivers the next amino acid in the sequence, amino acids are joined by peptide bonds
___ is the process of decoding DNA into messenger RNA.
transcription