Ch. 8 Microbial Genetics & Genetic Engineering ALL

What describes the origin of replication?

-located on the chromosome -AT-rich

A Nitrogen- containing molecule found in DNA and RNA that provides the basis for the genetic code is a nitrogenous ___________

Base

Point mutation that leads to a different amino acid being incorperated into a protein

missense mutation

The basic unit of DNA structure is the

nucleotide.

The ____________ is the site where the repressor binds to turn transcription of the structural genes off.

operator

A __________ is the physical expression of the genes present, and can change depending upon what genes are turned "on". A) plasmid B) chromosome C) phenotype D) genotype

phenotype

Which type of RNA composes ribosomal subunits together with protein?

rRNA

____ and proteins compose ribosome units.

rRNA

The pieces of DNA produced by restriction endonucleases are termed _____________ ___________

restriction fragments

During _______ DNA replication, the newly made double helices are composed of one strand from the parent template and one newly synthesized strand.

semiconservative

DNA fragments separate on an electrophoresis gel with the

smallest segments traveling furthest.

A change in DNA sequence arising from errors in replication that occur randomly is a/n

spontaneous mutation.

When a restriction enzyme makes a staggered cut across a strand of DNA, this is known as a

sticky ends

All of the following are true regarding eukaryotic chromosomes

the DNA is tightly coiled around histone proteins chromosomes vary in number from a few to hundreds. chromosomes can occur in pairs or singles

All of the following are true regarding eukaryotic chromosomes EXCEPT A) the DNA is tightly coiled around histone proteins. B) the chromosomes are located in the nucleoid. C) chromosomes vary in number from a few to hundreds. D) chromosomes can occur in pairs or singles.

the chromosomes are located in the nucleoid

.The lactose operon itself has three important features. Which of the following is NOT one of these features? A) the regulator B) the control locus C) the inducer D) the structural locus

the inducer

What is a method of vertical gene transmission?

Cell division

A _____________ is a discrete cellular structure composed of a neatly packaged DNA molecule.

Chromosome

The polymerase chain reaction is a method of

DNA amplification.

All of these statements are true about DNA replication

DNA ligase joins the small DNA fragments of the lagging strand. DNA polymerase is required to add new nucleotides to the growing ends of the DNA strands. RNA polymerase synthesizes the primers

Taq polymerase is a _________

DNA polymerase

What enzyme builds the new DNA strands in PCR?

DNA polymerase

Cellular genomes are composed of __________ whereas viral genomes may be either DNA or _____________

DNA;RNA

Regulatory RNAs

Determine gene expression in prokaryotes and eukaryotes

DNA strands are parallel, running in the same orientation. A) True B) False

F

Missense mutations are a type of frameshift mutation. A) True B) False

F

DNA strands are parallel, running in the same orientation

FALSE

Mutations are always harmful to cells.

FALSE

The protein's secondary structure is responsible for the order and type of amino acids in the protein chain. A) True B) False

FALSE

Translation is the first stage of gene expression.

FALSE

True or false: the chromosomal origin of replication is GC-rich to maintain its double-stranded structure under a wide range of conditions.

False

_______ ________ is a laboratory technique for separating DNA fragments according to length by employing electricity to force the DNA through a gel-like matrix

Gel Electrophoresis

The science of heredity is: -biology -reproduction -genetics

Genetics

Which term represents all of the genetic information within a cell? -Gene -Chromosome -Genome

Genome

The ________ is the genetic makeup of an organism that is ultimately responsible for an organism's expressed characteristics.

Genotype

What is used in the laboratory to separate strands of DNA?

Heat

Which one of the following would be the most likely to yield a recombinant cell after mating?

Hfr cell and F- cell

A sequence of DNA in a eukaryotic gene that does not code for proteins is called a(n)________

Intron

Primer RNA

Laid down in replication as a template for DNA sequence

The enzyme required to seal the sticky ends of DNA pieces after splicing is called ________

Ligase

__________ contains the codes for the sequence of amino acids in protein.

Messenger RNA

What amino acid sequence is encoded by the DNA template sequence 3'-TACCGCGCTCTACCG-'5

Methinonine-Alanine-Arginine-Aspartic acid- Glycine

A(n) _____________ is a permanent inheritable alteration in the DNA sequence of a cell.

Mutation

The major source of the genetic diversity among microorganisms upon which natural selection operates is:

Mutation

Chromosomes are located in the _________ of protozoal and fungal cells.

Nucleus

E.coli and other bacteria typically have _________ chromosome(s).

One

A(n) _________ in bacteria consists of regulatory gene, a control region, and structural genes.

Operon

The expressed characteristics resulting from the interaction of the particular genetic make up of an organsim and the environment is the ____________ of that organism.

Phenotype

During recombinant DNA technology, DNA is inserted into a vector. Identify a vector

Plasmid

A(n) _______ mutation involves any substitution of a single nucleotide that does not change the DNA reading frame.

Point

The ________ is the site in an operon where RNA polymerase binds to initiate transcription of the structural genes.

Promoter

What organic molecule is formed from chains of amino acids that are produced in translation?

Protein

In the central theme of molecular biology, DNA encodes _________ which encodes protein.

RNA

What enzyme cleaves specific locations on DNA and is used to splice genes in genetic engineering?

Restriction endonuclease

Two subunits of the ________ compose the site of protein synthesis.

Ribosome

Frameshift mutation nearly always results in a nonfunctional protein because every amino acid after the mutation is different from what was coded for in the original DNA. A) True B) False

T

Some mutations can be corrected using enzymes found in the cell. A) True B) False

T

The phenotype is the expression of the genotype. A) True B) False

T

Synthesizing amino acid sequences from messenger RNA is called

TRANSLATION

What is recombinant DNA technology?

The deliberate modification of genetic structure of an organism to create novel products or organisms

___________ is the process of decoding the messenger RNA into a polypeptide.

Translation

__________ are "jumping genes."

Transporons

All of the following are complementary nucleotide base pairs EXCEPT C-G A-U T-A U-C

U-C

Unlike DNA, RNA contains the nitrogenous base ________

Uracil

A genetic element such as a plasmid or a bacteriophage that is used to introduce genetic material into a cloning host during recombinant DNA experiments is called a:

Vector

Restriction endonucleases are enzymes which cut DNA at a specific palindromic sequence. They are produced

by bacteria to protect against viral infection.

In E. coli, Hfr cells

can pass main chromosome genes to a recipient cell.

Most amino acids are encoded by several different codons. This is referred to as the ----------of the genetic code

degeneracy

Gel electrophoresis separates DNA fragments using

electric current

In eukaryotic genes, introns are interspersed between coding regions called __________, that will be translated into protein.

exons

True or false: Gel electrophoresis patterns are the same in different individuals of the same species

false

Identify the purines

guanine/adenine

The matching nucleotide base pairs in DNA are bound to one another by __________ bonds.

hydrogen

What is the importance of PCR?

increases the amount of DNA in a sample

what is the complementary DNA sequence to the DNA template 3'-ATACTAAAATTT-5'?

5'-TATGATTTTAAA-3'

Name three steps associated with PCR

Denuturing(melting)DNA Annealing of primers Elongationm of target DNA

_______ are segments of DNA that contain information used to synthesize groups of related proteins.

Genes

__________ __________ is the enzyme that can convert RNA into DNA

Reverse Transcriptase

Codons of mRNA temporarily bond to anticodons of tRNA during translation.

TRUE

Hfr cells transfer genes to recipient cells in a particular order.

TRUE

In prokaryotes, translation of an mRNA molecule can begin before transcription of the mRNA molecule is completed.

TRUE

Organismal genetics observes the heredity of the whole organism. A) True B) False

TRUE

Palindromes are sequences of DNA that are identical when read from the 5' to 3' direction on one strand of DNA and from the 5' to 3' direction on the other strand.

TRUE

The process of transcription ______ results in the release of a completed RNA transcript

Termination

Codons are found in

mRNA

Which type of RNA is a copy of the DNA template corresponding to a protein-encoding gene?

mRNA

The spliceosome is comprised of

- RNA -Protein

A codon contains how many nucleotides?

3

Which template DNA sequence encodes the peptide sequence Phenylalanine-leucine-aspartic acid-valine?

3'-AAAAACCTACAT-5'

If a DNA molecule contains 15% adenine nucleotides, what percent of cytosine does it contain?

35%

Which of the following is an example of a palindrome?

5'-AAGCTT-3' 3'-TTCGAA-5'

This recognizes codones on the mRNA

Anticodone of tRNA

The genes of which microorganism(s) are arranged as operons?

Bacteria

What is used in the laboratory to renature DNA into its normal double stranded for?

Cooling

In the bacterium Escherichia coli, where is the chromosome located?

Cytoplasm

Transcription occurs in the ________ of bacteria and the _______ of yeast cells.

Cytoplasm; Nucleus

Genes code for all of the following EXCEPT A) structural components B) regulatory components C) RNA D) DNA

DNA

Genomes of cells are composed of ______________

DNA

During transcription, RNA polymerase synthesizes ________ from a(n) _________ template.

RNA; DNA

The primary intent of _______ DNA technology is to combine the genetic material from two organisms

Recombinant

What refers to the transfer of genes between donor and recipient microorganisms?

Recombination

Ribozymes

Remove introns in eukaryotes

DNA _________ must occur prior to cell division to ensure that each new cell has a complete set of DNA chromosome(s)

Replication

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

The mRNA squence AUG, specifying the first amino acid in protein sequences, is called the ________ codon

Start

_______ genes code for proteins

Structural

What is a cloning host?

The organism that receives and replicates a foreign piece of DNA inserted during a genetic engineering experiment

All DNA nucleotides contain:

The same sugar and phosphate, but different nitrogenous bases

Consider the polypeptide sequence encoded by the following DNA: TACAAAGAAATT If base number 6 is changed to G, how will this affect the polypeptide?

There will be no change in the polypeptide

All of these statements are true of plasmids

They may encode genes that enhance the pathogenicity of an organism They are small, circular molecules of DNA that can carry genes for heavy metal resistance. They can be transferred between bacteria during conjugation. They may contain antibiotic resistance genes.

________ and _________ of the foreign gene to make the protein product will occur if a cloning host receives the recombinant plasmid.

Transcription;Translation

Which type of horizontal gene transfer has been linked to the virulence of bacteria such as Clostridium, Streptococcus pyogenes, and Corynebacterium diphtheriae?

Transduction

tRNA carries ________ _________ to the ribosome during protein synthesis.

amino acids

Most plasmid vectors contain an _________ ________ gene as well as the gene of interest.

antibiotic resistance

The Ames test is used to identify potential carcinogens on the basis of their ability to A) relocate genes from one section of the genome to another. B) cause back-mutations in bacteria. C) cause replication. D) induce excision repairs

cause back-mutations in bacteria.

The first challenge in gene __________, or recombinant DNA technology, is locating and isolating a target gene.

cloning

Sexual reproduction in which a plasmid, or other genetic material, is transferred by a donor to a recipient cell via a direct connection is termed

conjugation.

DNA viruses tend to replicate in the nucleus while RNA viruses replicate in the A) mitochondria. B) ribosome. C) Golgi apparatus. D) cytoplasm

cytoplasm

According to the rules of complementary base pairing, the nitrogenous base ______ forms hydrogen bonds with guanine.

cytosine

Major types of recombination include all of the following EXCEPT conjugation transformation transcription transduction

transcription

Small stretches of DNA that can move within a genome are referred to as

transposons.

DNA replication involves all of these steps

unzipping hydrogen bonds between complementary base pairs. synthesizing new DNA matching complementary base pairs. uncoiling parent DNA.

Photoactivation to repair DNA damage requires what?

-Visible light -DNA photolyase

What nitrogenous bases is found in both DNA and RNA?

- Adenine

The process of eukaryotic transcripts:

- The gene is transcribed to mRNA -A series of adenosines is added to the mRNA -A spliceosome excises introns from the mRNA -The mRNA leaves the nucleus -The mRNA is translated into protein

Recombinant human insulin is produced from:

-Yeast -Bacteria

What are events of translation elongation?

-Amino acids are joined by peptide bonds -The ribosome shifts from one codon on the mRNA to the next -A tRNA delivers the next amino acid in the sequence

what are true for repressible operons?

-Code for anabolic enzymes -Usually turned on unless product is in excess

What are true for inducible operons?

-Code for catabolic enzymes -Usually turned off unless substrate is present -Example is the lac operon

The enzymes the function in DNA replication

-DNA polymerase -Ligase -Helicase

The 3 basic steps in order for PCR?

-Denaturation -Priming -Extension

What two components of a nucleotide are bound to form the backbone of a DNA strand?

-Deoxyribose sugar -Phosphate

The steps in excision repair

-Enzymes recognize a mismatch in the two DNA strands -Enzymes remove the nitrogenous base on one strand -DNA polymerase 1 synthesizes new DNA as needed -Ligase seals the phosphate backbone of the DNA

The process of naming for restriction enzymes

-First letter of bacterial genus -First 2 letters of bacterial species -The order discovered in the bacterium

What are the 3 major types of RNA

-Messenger -Ribosomal -Transfer

What are the 3 components of a DNA nucleotide?

-Nitrogenous base -Phosphate -Deoxyribose sugar

What makes good cloning vectors?

-Plasmids -Bacteriophages

How does RNA differ from DNA in bacteria and eukaryotes?

-RNA is a single- stranded -In RNA, Uracil replaces thymine

The general steps in order for the Recombinant DNA procedure

-Remove and isolate a selected gene from a donor organism -Insert the gene of interest into a vector -Use vector to deliver selected gene into cloning host.

What is commonly shared between bacteria through the process of conjugation?

-Resistance plasmids -Genes for Virulence factors

What events initiate translation?

-Ribosome scans to find AUG on the mRNA transcript -Assembly of the ribosomal subunits

________ mutations occur when errors are made in DNA replication whereas _________ are caused by exposure to radiation or chemical agents.

-Spontaneous -Induced

What strategies are used to isolate a target gene for use in recombinant DNA technology?

-Synthesis of cDNA -Amplification by PCR -Gene probing for desired sequences -Digestion with endonucleases

What are differences between eukaryotic and bacterial protein synthesis?

-Transcription and translation are simultaneous in bacteria but not eukaryotes -The first amino acid is slightly different

Which two types of horozontal gene transfer do NOT require direct contact between the donor and the recipient cells?

-Transduction -Transformation

What methods are used in gene transfer in bacteria?

-Transformation -Transduction -Conjugation

There are hundreds of different restriction enzymes that each cut ________ at a different palindrome sequence

DNAns

The process of bacteria turning on or off a group of genes that changes its phenotype is called ________ ________

Phase variation

_______ involves the transfer of DNA via bacteriophages.

Transduction

Vertical gene transfer

Transfer of DNA from a parent organisms during reproduction

Horizontal gene transfer

Transfer of DNA from a source other than the parent organisms

If a microbiologist wanted to insert a human gene into a bacterial cell, which type of horizontal gene transfer would be a useful means of accomplishing this goal?

Transformation

Which gene transfer method involves the uptake of free DNA by competent bacterial cells?

Transformation

Deoxyribose is the:

sugar in DNA