Modifying Biology Chapter 18 Quiz
Chemotherapeutic treatment for breast cancer depends on the absence or over-expression of the __________ gene(s).
ERa, PR, and HER2
Which of the following best describes the makeup of the human genome?
Genes for noncoding RNA make up the majority of meaningful genetic information in the human genome.
What gene has been called the "guardian angel of the genome?"
The p53 gene
What is the role of proteasomes?
They are giant protein complexes that recognize ubiquitin and degrade the tagged proteins.
In the lac operon, the inducer is __________.
allolactose, the isomer of lactose
Although the number of genes in the human genome is surprisingly low compared to less complex organisms, the number of possible products from those genes is greatly amplified by __________.
alternate arrangements of eons form a primary transcript
Post-transcritptional processing of a pre-mRNA allows for differential cell expression by a process called ________.
alternative splicing
In prokaryotic genomes, groups of functionally related genes along with their promoters and operators are found together in __________.
an operon
The top (tryptophan) operon is an example of a(n) __________ that is controlled by __________.
anabolic pathway; feedback inhibition
Cytoplasmic determinants __________
are RNAs, proteins, and other substances produced by the mother and deposited in the egg
Cell type-specific transcription is accomplished __________.
by specific enhancer control elements interacting with cell type-specific transcription factors
Gene expression in bacteria is regulated primarily by __________.
controlling the transcription of genes into mRNA
A cancer cell __________.
does not respond to the chemical signals that control cell division
In Drosophila development, the anterior-posterior axis of the embryo is determined by __________.
egg-polarity genes
In a eukaryote, activating transcription factors may stimulate gene expression by binding to a DNA site called a(n) __________.
enhancer
In Drosophila development, pattern development in the late embryo, larva, and adult is controlled by __________.
homeotic genes
The control of gene expression is more complex in multicellular eukaryotes that in prokaryotes because __________.
in a multicellular eukaryote, different cells are specialized for different functIons
Small noncoding RNAs (ncRNAs) called piwi-interacting RNAs, or piRNAs, __________.
induce the formation of heterochromatin and block the expression of movable DNA elements called transposons.
The lac operon is an example of a(n) __________ operon.
inducible
Specific cells that apparent undifferentiated under the microscope but are already fated to become muscle cells are called __________.
myoblasts
In eukaryotes, histone acetylation __________.
promotes transcription
What two genes are often mutated in colon cancer?
ras and p53
The trp (tryptophan) operon is an example of a(n) __________ operon.
repressible
In general, operons that encode the enzymes of a biosynthetic (anabolic) pathway (such as the top operon) are __________, and those encoding the enzymes of a catabolic pathway (such as the lac operon) are __________.
repressible; inducible
In the top (tryptophan) operon, the __________ binds to the product of the top operon synthesis pathway, called __________, forming the __________.
repressor protein; tryptophan; active repressor
MicroRNAs binding to complementary sequence on an mRNA __________.
results in either blocking translation or degrading the targeted mRNA
In an inducible operon, the inducer is often the __________ in the pathway being regulated; the inducer binds to the __________, thus rendering it __________.
substrate; repressor; inactive
Both repressible and inducible operons control gene expression at the level of __________.
transcription
MyoD promoted muscle cell development by __________.
turning on the expression of multiple muscle-related genes
