Chapter 11 Bio Quiz – Flashcards

Unlock all answers in this set

Unlock answers
question
A mistake during DNA replication prevents the trp repressor from binding to the operon operator. When these cells are placed in a solution containing chicken broth, what happens?
answer
Tryptophan would bind to the repressor.
question
What controls the way in which a zygote differentiates?
answer
Selective genes are turned on and off, depending on the fate of the cell.
question
In female mammals, the inactive X chromosome in each cell
answer
becomes a Barr body.
question
The coding regions of a gene (the portions that are expressed as polypeptide sequences) are called
answer
exons
question
Alternative RNA splicing has revealed inaccuracies in the one gene - one polypeptide hypothesis. Why?
answer
Transcription of the same gene can lead to the production of different mRNAs.
question
After translation is complete, the insulin polypeptide is activated by _____
answer
the cutting of the initial translation product to yield two shorter chains joined together by sulfur linkages
question
Which of the following statements about fruit fly development is false?
answer
The location of the head and tail ends of the egg is primarily determined by the location of sperm entry during fertilization.
question
A researcher performs a DNA microarray but forgets to add the enzyme reverse transcriptase. This is important because the enzyme makes _____ from a(n) _____ template.
answer
cDNA ... mRNA
question
To initiate a signal transduction pathway, a signal binds to a receptor protein usually located in the
answer
plasma membrane.
question
Researchers have used yeast mating systems as model systems to study
answer
signal transduction systems
question
Half the trees in an orchard were derived from rootstock "A" and half from rootstock "B," but all the trees had the same scion. If the trees grafted onto rootstock "A" were infected by a parasite that causes blossom rot, the trees grafted onto rootstock B
answer
would be very likely to become infected, because the remaining scions are genetically identical to those that are already infected.
question
Using nuclear transplantation, it is possible to generate _____ for therapeutic uses.
answer
blastocysts
question
Since the first animal was produced using a fully differentiated cell, a number of observations have been made. Which of the following statements is true in regard to reproductive cloning?
answer
Cloned animals develop chronic conditions that are usually only associated with old age.
question
Stem cells could be immensely important in the treatment of which of the following conditions?
answer
spinal cord injuries
question
Which of the following statements regarding stem cells is false?
answer
Adult, but not embryonic, stem cells can be grown in laboratory culture.
question
Proto-oncogenes have the potential to become oncogenes. Which of the following is most likely to lead to cancer?
answer
a mutation that causes the proto-oncogene to become overactive
question
A gene that can cause cancer when present in a single copy in a cell is called a(n)
answer
oncogene.
question
Colonoscopy is the examination of the large colon. It allows for visual diagnosis of ulcers and polyps, which may lead to colon cancer. A polyp _____.
answer
is a cluster of abnormal cells
question
The development of colon cancer occurs slowly, and colon cancer is more frequently seen in the elderly than the young. This is most likely because
answer
four or more somatic mutations must occur to give rise to the cancer, which takes time.
question
The carcinogen known to cause the most cases and types of cancer is
answer
tobacco
question
In a prokaryote, a group of genes with related functions, along with their associated control sequences, defines
answer
an operon
question
Anhidrotic ectodermal dysplasia is an X-linked disorder that results in the absence of sweat glands. How would this condition be manifested in a heterozygous female?
answer
She would have a random pattern of tissue with and without sweat glands.
question
In eukaryotic cells, several proteins are involved in the process of transcription. This process involves enhancers that are _____.
answer
bound by activators, causing DNA to bend
question
When are DNA molecules the least tightly coiled?
answer
S phase of interphase
question
MicroRNA (miRNA) controls _____.
answer
translation
question
After translation is complete, the insulin polypeptide is activated by _____.
answer
the cutting of the initial translation product to yield two shorter chains joined together by sulfur linkages
question
In embryonic mice, a homeotic gene controls development of the neck, which includes the larynx and thymus. If this gene were deleted, a full-term mouse would show _____.
answer
lack of development of the larynx and thymus
question
Yeast are able to communicate with each other
answer
through chemical signaling
question
Since the first animal was produced using a fully differentiated cell, a number of observations have been made. Which of the following statements is true in regard to reproductive cloning?
answer
Cloned animals develop chronic conditions that are usually only associated with old age.
question
The Rb protein prevents mitosis by inhibiting cells from entering S phase. Human papillomavirus (HPV) is thought to inhibit the action of the Rb protein in cervical epithelial cells. What would be the effect of cervical cells being infected with HPV?
answer
the mitotic rate would increase
question
A gene that can cause cancer when present in a single copy in a cell is called a(n)
answer
oncogene
question
Mutations in the proto-oncogene ras and the tumor suppressor gene p53
answer
disrupt normal regulation of the cell cycle.
question
n humans, the most common cancer is _____.
answer
lung cancer
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New