Micro ch. 7

Match the enzymes involved in DNA replication with their functions.... DNA ligament

Joining fragments of DNA

Type of RNA molecule that contains the genetic information decoded during translation - messenger

MRNA

Who was the first person to discover genes

Mendel

Translation of mRNA into protein begins before transcription is complete in prokaryotes or eukaryotes?

Prokaryotes

Match the enzymes involved in DNA replication with their functions.... Helicase

Unwinding the DNA helix

changes in the characteristics of surface proteins

antigenic variation

methylated guanine derivative at the 5' end

cap

proteins involved in folding newly synthesized proteins into functional structures

chaperones

An open reading frame or a possible protein-encoding region of prokaryotic DNA is A. a section of DNA that starts with a stop codon, indicating the end of one protein-encoding region and the start of another. B. an area of the DNA that binds proteins involved in the initiation of transcription. C. a region of DNA that begins with a start codon (ATG) and ends with a stop codon. D. any section of DNA that is open for transcription.

C. A region of DNA that begins with a start codon (ATG) and ends with a stop codon

Which of the following occurs in both prokaryotes as well as eukaryotes? A. DNA replication B. Transcription C. All of these D. Translation

C. All of these

Phase variation is a phenomenon used by some bacteria (such as E. coli) to evade host immune mechanisms. In this process, the cells A. actively secrete a destructive enzyme that destroys white blood cells. B. invade white blood cells and hide within them. C. alternately turn genes on/off to adjust bacterial behavior. D. express certain genes that are only useful when expressed by a critical mass.

C. Alternately turn genes on/off to adjust bacterial behavior

Binding of an activator to an activator binding site on DNA: A. Binds DNA, RNA, and ribosomes together B. Acts as a primer for RNA synthesis C. Enhances the ability of RNA polymerase to bind to the promoter site

C. Enhances the ability of RNA polymerase to bind to the promoter site

Early in the process of DNA replication, the enzyme ______ separates the two strands. A. primase B. replicase C. helicase D. endonuclease

C. Helicase

What would be the direct result of a bacterium losing the ability to produce DNA ligase? A. RNA primers could not be synthesized B. Transcription could no longer initiate C. Okazaki fragments could no longer be joined together

C. Okazaki fragments could no longer be joined together

Which of the following is not involved in the initiation of translation? A. Ribosomal subunits B. mRNA C. RNA polymerase D. All of these are involved

C. RNA polymerase

_______ are groups of three bases in mRNA that specify one amino acid in the amino acid chain

Codons

Synthesized constantly, these enzymes usually play a critical and indispensable role in central metabolic pathways

Constitutive

Where does translation occur in eukaryotes?

Cytoplasm

In the absence of lactose, the lac repressor is A. inactive and cannot bind to the operator. B. inactive and cannot bind to the promoter. C. inactive and can bind to the operator. D. active and can bind to the operator. E. active and cannot bind to the operator.

D. Active and can bind to the operator

Metagenomics is the analysis of A. proteins produced by a specific microbe within a mixed population of microbes. B. a specific microbial genome within a mixed population of microbes. C. proteins produced by all microbes in a population. D. total microbial genomes in an environment.

D. Total microbial genomes in an environment

the complete set of chromosomes and genes in an organism is called the ________

genome

study of the total microbial genomes in an environment is called ______.

metagenomics

the routine switching on and off of certain genes

phase variation

adenine derivatives at the 3' end

polyadenylation

A segment of DNA encoding a protein or an RNA molecule is a _____.

Gene

The two strands of DNA are joined together by ______ __________.

Hydrogen bonding

Not routinely produced at significant levels, but their synthesis can be turned on when needed. These are often used in the transport and breakdown of specific energy sources

Inducible

The lac operon is _______

Inducible

A fundamental aspect of gene regulation lies in the _________ of mRNA molecules. Because of this trait, these molecules won't remain in the cell long after transcription has been turned off by the cell, regulating gene expression.

Instability

If a protein-encoding gene contains introns and eons, it is likely that .....?

It is a eukaryotic gene

A _______ is the physical expression of the genes present and can change depending upon what genes are turned "on."

Phenotype

The initial transfer RNA occupies the _____ site on the ribosome

P site

The 3 basic pairs of a nucleotide are...?

Phosphate, deoxiribse sugar, nitrogenous base

What 3 components make up RNA structure?

Phosphate, nitrogenous base, ribose sugar

Arrange the following proteins in the correct order in which they participate in DNA replication. 1 = Primase 2 = Helicase 3 = DNA ligase 4 = DNA polymerase

2,1,4,3

If a 75 base-pair fragment of DNA has 25 cytosines in it, how many adenines would you expect it to have?

50

After the completion of DNA replication in prokaryotic cells, A. each daughter cell contains DNA with one newly synthesized DNA strand and one original parental strand. B. both daughter cells contain only newly synthesized DNA. C. one daughter cell contains the original parental DNA, while the other contains newly synthesized DNA. D. both daughter cells have identical copies of DNA.

A, B

Changing your t-shirt for one of a different color is analogous to _______ ________.

Antigenic variation

The two strands of a DNA molecule are A. Antiparallel B. Parallel C. Identical

Antiparallel

Which of the statements about DNA and RNA are FALSE? A. At the replication fork, one DNA strand is a leading strand and the other is a lagging strand. B. RNA polmerase requires a primer. C. Prokaryotic RNA is typically polycistronic. D. Eukaryotic RNA is typically polycistronic. E. The minus strand of DNA is complementary to RNA.

B,D

In the absence of lactose, A. An activator binds to glucose B. A repressor protein binds to the operator C. An inducer binds to the operator site of the operon

B. A repressor protein binds to the operator

Antigenic variation is a phenomenon used by some bacteria (such as Neisseria gonorrhoeae) to evade host immune mechanisms. In this process, the cells A. invade white blood cells and hide within them. B. can change the characteristics of certain surface proteins on the bacteria, forcing immune response to constantly adapt (which takes time). C. alternately turn genes on/off to adjust bacterial behavior. D. actively secrete a destructive enzyme that destroys white blood cells.

B. Can change the characteristics of certain surface proteins on the bacteria, forcing immune response to constantly adapt

Which of the following statements is FALSE? A .Some types of bacteria randomly change their gene expression. B. Genes for constitutive enzymes can be turned on and off as necessary. C. Alternative sigma factors can be used to "turn on" sets of genes, such as those for endospore formation. D. Some types of bacteria can sense the density of cells within their own population.

B. Genes for constitutive enzymes can be turned on and off as necessary

To which part of a DNA molecule are nucleotides added? A. The phosphate group on the 3' end of the molecule. B. The hydroxyl group on the 3' end of the molecule. C. The phosphate group on the 5' end of the molecule. D. The hydroxyl group on the 5' end of the molecule.

B. The hydroxyl group on the 3' end of the molecule

Match the enzymes involved in DNA replication with their functions..... DNA polymerase

DNA synthesis

The lac operon is expressed when A. glucose is high and lactose is absent. B. glucose is high and lactose is present. C. glucose is low and lactose is absent. D. glucose is low, regardless of the presence or absence of lactose. E. glucose is low and lactose is present.

E. glucose is low and lactose is present

T/F: Eukaryotic mRNA usually specifies multiple proteins

False

T/F: On one parent strand, the polymerase synthesizes DNA in the 5' to 3' direction, while on the other, it synthesizes DNA in the 3' to 5' direction

False

T/F: both DNA and RNA are usually double-stranded molecules

False

T/F: the most difficult aspect of the new field of metagenomics is generating sequence data reliably and cost-effectively.

False

T/F: the plus (+) strand of DNA acts as a template during transcription

False

T/F: the purpose of RNA synthesis is to provide a new copy of DNA as the original strand deteriorates over time.

False

T/F: the tree potential reading frames found on mRNA generally code for the same amino acid

False

T/F: translation occurs on ribosomes only in prokaryotes

False

T/F: translation of eukaryotic mRNA can occur in the nucleus after exon are spliced together

False

RNA is a chain of _________.

Nucleotides

Where does transcription occur in eukaryotes?

Nucleus

An _________ is a cluster of genes that perform related functions found in _________.

Operon; prokaryotes

Coordinated sets of genes that are regulated as a single unit are referred to as _________.

Operons

What component of RNA is different from one individual to the next?

Order of nitrogenous bases

On one of the strands of bacterial DNA, the new complementary strand is synthesized discontinuously into small pieces of DNA called _________.

Ozakaki fragments

Transcription begins when RNA polymerase binds to the ________ on DNA

Promoter

Match the enzyme involved in DNA replication with their functions.... Primase

RNA primer synthesis

Type of RNA molecule present in ribosomes

RRNA

These are produced routinely, but their synthesis can be turned off when they are no longer required. These are generally used in anabolic (biosynthetic) pathways.

Repressible

Transcription is often controlled by DNA-binding proteins. A __________ is a regulatory protein that blocks transcription, while an _______ is a regulatory protein that facilitates transcription

Repressor; activator

In translation, the codon at which the process begins is called the ____ codon, while the codon at which the process ends is called the ____ codon.

Start; stop

Type of RNA molecule that carries amino acids to the growing peptide chain during translation - transfer

TRNA

Match the enzymes involved in DNA replication with their functions.... DNA gyrase

Temporary breaking of DNA strands

The codon ACA encodes ________.

Threonine

An alternative sigma factor would directly affect which process?

Transcription

The process of synthesizing RNA from a DNA template is _________

Transcription

In order for a cell to make ribosomes, which of the following must be happening?

Transcription and translation

Decoding RNA to synthesize protein

Translation

T/F: DNA polymerase can only add nucleotides in a certain direction

True

T/F: In prokaryotes, the mRNA transcript encounters ribosomal subunits immediately as it leaves the DNA

True

T/F: Only eukaryotic mRNA is processed before translation

True

T/F: genes controlled by an activator have ineffective promoters

True

T/F: prokaryotes lack membrane-enclosed organelles

True

The pentose sugar in RNA is _______, while in DNA the pentose sugar is _______.

ribose; deoxyribose

turning DNA into RNA

transcription