BSC 108 - Test 3
One of the most difficult ethical issues related to DNA technology is the question, __________.
"How do we prevent genetic information from being used in a discriminatory manner?"
Flower color in snapdragons is an example of incomplete dominance. If a red-flowered plant is crossed with a white-flowered plant, the F1 generation has pink flowers. If a pink-flowered plant is crossed with a pink-flowered plant, the progeny plants will be __________.
25% red, 50% pink, and 25% white
Early geneticists wondered how only four nucleotides could specify the sequence of 20 amino acids in proteins. Today we know that there is a genetic code in which __________ nucleotide(s) code(s) for each amino acid.
3 The number of possible three-letter codes is 4^3, or 64. This is more than the number of amino acids. Thus, the code can be redundant. In some cases, there is more than one codon that codes for the same amino acid.
What is the expected phenotype ratio in the F2 generation from a true-breeding monohybrid cross?
3 dominant to 1 recessive
A couple has two female children. What is the probability that their next child will be male?
50%
Which of the following statements about the Zika virus is not true? A) The mosquito that carries the Zika virus bites both night and day. B) Zika first emerged in human populations in 2016. C) In addition to transmission by mosquito vectors, Zika can be transmitted from mother to baby and from one sex partner to another. D) It consists of a relatively simple structure of RNA and protein.
B) Zika first emerged in human populations in 2016.
Which of the following choices best defines "recombinant DNA technology"? A) an independent assortment of alternate alleles B) combining genes from different species C) homologous pairs of chromosomes D) manipulated crossing over E) combining alternate alleles on the same chromosome
B) combining genes from different species
Which of the following choices best defines "recombinant DNA technology"? A) an independent assortment of alternative alleles B) combining genes from different species C) cloning genes from homologous pairs of chromosomes D) manipulated crossing over E) combining alternate alleles on the same chromosome
B) combining genes from different species
What makes a good Genetics Research model organism?: A) readily available B) short generation time C) cost effective D) all of the above
D) all of the above
Which one of the following choices is true of tRNA? A) tRNAs are extremely small molecules. B) there are four types of tRNA C) tRNAs carry special sequences known as codons D) each tRNA binds a specific amino acid
D) each tRNA binds a specific amino acid
There has been a lot of discussion about stem cell research in mainstream literature (i.e. newspapers). Stem cells come from all of the following except: A) umbilical cord B) embryos C) bone marrow D) stem cells can come from all of these sources
D) stem cells can come from all of these sources
Chromosomes contain most of the cell's ___________ which acts as the molecule of heredity.
DNA
What technique can be used to investigate murders, determine paternity or maternity, and study relationships with ancient DNA?
DNA profiling
In humans, the presence or absence of dimples is a trait controlled by a single gene. What is the genotype of an individual who is heterozygous for dimples? (use D as the genotypes)
Dd
Mutations can be good, bad or result in no change depending on: A) the type of change B) where the change in DNA occurs C) if the change is detected and fixed before replication D) how it affects the organism and its survival E) all of the above
E) all of the above
Possible uses of reproductive cloning include ______. A) restocking populations of endangered animals B) the production of potentially valuable drugs C) the production of organs in pigs for transplant into humans D) the production of genetically identical animals for experimentation E) all of the above
E) all of the above
Viruses ______________: A) sit on the fence between life and nonlife B) use either DNA or RNA as their genetic material C) only infect sick people D) all of the above are correct E) only a and b are correct
E) only a and b are correct
How do new viruses arise? A) mutation of existing viruses B) not taking all your antibiotics C) spread to new host species D) all of the above are correct E) only a and c are correct
E) only a and c are correct
Which of the following processes occurs in the cytoplasm of a eukaryotic cell? A) transcription B) DNA replication and translation C) DNA replication D) translation and transcription E) translation
E) translation
True or False: Therapeutic cloning is used to create whole organisms called clones
False
True or False? Humulin caused more adverse reactions in humans as compared to insulin from cows and pigs
False
True or False? In DNA, the nucleotides are on the outside of the double helix
False
True or False? Inherited pairs of genes are found in each of the parental crosses
False
True or False? The flow of genetic information in a cell is RNA to DNA to Protein
False
True or False? The flow of genetic information in a cell is RNA to DNA to protein
False
What are the genotypes for blood group A?
I^A I^A or I^A i
What are the genotypes for blood group AB?
I^A I^B
What are the genotypes for blood group B?
I^B I^B or I^B i
Most plant viruses have __________ as their genetic material.
RNA
The influenza virus, a deadly infectious agent found around the world, is composed of __________ and __________.
RNA protein
One strand of a DNA molecule has the base sequence ATAGGT. The complementary base sequence on the other strand of DNA will be _____.
TATCCA
Why, of all cell types, do embryonic stem cells (ES cells) have the greatest potential for use in the treatment of disease?
They are undifferentiated cells that have the potential to differentiate into all of the different specialized cells of the body.
True or False? Dominant genes are always expressed phenotypically?
True
Who is credited with determining the structure of DNA?
Watson and Crick
The sex chromosomes in humans that make an individual a male are _____.
X and Y
Which of the following is in the correct sequential order?: a better breed of corn is created through artificial selection, a tadpole is cloned, a test tube baby is born, Dolly is born
a better breed of corn is created through artificial selection, a tadpole is cloned, a test tube baby is born, Dolly is born
Tay Sachs disease runs in Rebecca's family. When she looked at her family pedigree, she saw a shaded circle. This represented __________.
a female with Tay Sachs
Which of the following is an example of a transgenic organism?: a) a bacterium with human gene for producing insulin b) a bacterium found with a plasmid that provides protection against an antibiotic c) a "test-tube" baby produced via in vitro fertilization d) Dolly, the cloned sheep
a) a bacterium with human gene for producing insulin
Surprising new evidence has shown that, in some cases, environmental factors can modify chromosomes in such a way that changes the expression of genes without changing genes themselves or any part of the DNA sequence. These modifications are called epigenetic effects. Epigenetic effects can sometimes even be passed from generation to generation. In what way would this kind of "inheritance" be an exception to Mendel's laws?
according to Mendel's laws, the effects of our environment are not passed on to the next generation
Gene therapy involves __________.
adding a functioning version of the defective gene to the cells of an individual
Which one of the following is a list of the four bases contained in DNA?
adenine, guanine, cytosine, thymine
Crossing a plant with white flowers and a plant that is homozygous for purple flowers results in offspring with what color combinations? (white is the recessive trait)
all flowers will be purple
The different forms of a gene are called ____________
alleles
Color-Blindness is an example of _________
an X-linked gene
Linked genes are genes that __________.
are on the same chromosome
Chromosomes that are not sex chromosomes are called ______.
autosomes
A duplicated chromosome remains tightly paired with its partner at a region called the ________________.
centromere
Which of the following is an animal virus? A) lambda virus B) T4 virus C) chicken pox virus D) tobacco mosaic virus
chicken pox virus
DNA and protein together form a complex called _____________.
chromatin
The DNA of every eukaryotic cell is stored in one or more _____________ located in the ___________.
chromosomes nucleus
Using a cell taken from a multicellular organism to grow a genetically identical new organism is called _____.
cloning
one of the questions early geneticists had to answer was how only four nucleotides can specify placement of 20 amino acids in proteins. Today we know that _______, a sequence of three adjacent nucleotides, determine the insertion of a specific amino acid in a polypeptide chain
codon
Restriction enzymes __________________________.
cut DNA at specific nucleotide sequences
Although all of the cells in your body contain a complete set of DNA, different types of cells arise because ______________
different genes are switched on and off in each type of cell
Although all of the cells in your body contain a complete set of DNA, different types of cells arise because_________.
different genes are switched on and off in each type of cell
Although all of the cells in your body contain a complete set of DNA, different types of cells arise because__________.
different genes are switched on and off in each type of cell
The process by which cells become specialized is called ______________.
differentiation
Ethical dilemmas raised by DNA technology and knowledge of the human genome include ______. a) the appropriateness of creating new plants, animals, and microorganisms b) the safety of GM foods c) the potential discrimination against people predisposed to certain diseases d) the potential for interfering in evolution e) all of the above
e) all of the above
What is a difference between embryonic and adult stem cells?
embryonic stem cells are UNdifferentiated adult stem cells are PARTIALLY differentiated
Over thousands of years, genetic tinkering has led to the incredible variety of body types and behaviors we have today, from huge, docile Great Danes to tiny, spunky Chihuahuas. ________________
evolution
Genetically modifying human ______ cells may directly affect future generations.
gametic
________________ is defined as a person's genetic makeup.
genotype
In November of 2016, the World Health Organization declared that the Zika global health emergency was over. What was the rationale for this declaration?
health officials now expect Zika to be a long-term problem rather than a short-term emergency
One of the critical aspects of Watson and Crick's discovery of the structure of DNA was that it __________.
helped explain how DNA molecules can be copied to produce identical DNA molecules
What is the source of a viral envelope?
host cell membrane
The world's first genetically engineered pharmaceutical product was ______.
humulin
What are the genotypes for blood group O?
ii
Mendel crossed homozygous plants having round-yellow seeds with plants having wrinkled-green seeds. The union of gametes from the parental generation yielded hybrids heterozygous for both characters. All of these offspring had round-yellow seeds. ________________
information flow
Which of the following are the three phases of translation?
initiation, elongation, and termination
The clogging of blood vessels causes a cascade of symptoms; blood flow to body parts is reduced, resulting in periodic fever, severe pain, and damage to the heart, brain, and kidneys. The abnormal cells are destroyed by the body, causing anemia and general weakness. ____________________
interactions within biological systems
What is the function of reverse transcriptase?
it catalyzes the formation of DNA from an RNA template
A mutation that changed the third nucleotide in the DNA sequence specifying the amino acid glycine from an A to a T would have what effect?
it would have no effect, because of redundancy in the genetic code, any amino acid-coding DNA triplet with two cytosines specifies the amino acid glycine regardless of the third nucleotide.
In humans, the ___________ determines the sex of the offspring because _________
male the male can contribute either an X or a Y chromosome
Transcription is the ______.
manufacture of a strand of RNA complementary to a strand of DNA
Blood type is an example of __________
multiple allele and codominance
Blood type is an example of __________________.
multiple allele and codominance
What is the ultimate source of all diversity?
mutation
What is defined as an organism's expressed physical traits?
phenotype
A supplemental appendix is to a book as a ____________ is to a bacterial chromosome.
plasmid
What is the name of the biotechnology instrument used to make multiple copies of a DNA sample?
polymerase chain reaction
You cross a true-breeding red-flowered snapdragon with a true-breeding white-flowered snapdragon. All of the F1 are pink. What can you say about the alleles for the parental traits?
red and white show incomplete dominance
The H allele specifies a cell-surface receptor protein that liver cells use to mop up excess "bad cholesterol" from the blood. Each receptor protein type only accepts specific molecule shapes. With only half as many receptors on their liver cell membranes as HH individuals, heterozygotes can remove much less excess cholesterol. _______________
relationship of structure to function
HIV requires an enzyme called _____ to convert its RNA genome to a DNA version
reverse transcriptase
Electrophoresis is used to __________.
separate fragments of DNA
The genetic material of HIV consists of _____.
single stranded RNA
Before a cell divides, it copies all of its chromosomes. While the two copies of a chromosome are attached they are called ____________.
sister chromatids
Gel electrophoresis separates pieces of DNA based on _________.
size/length
The anticodon of an incoming __________ molecule, carrying its amino acid, pairs with the mRNA __________ at the ribosome.
tRNA codon
In frogs, when the nucleus of an intestinal cell of a tadpole is transferred to an egg whose nucleus has been removed (nuclear transplantation), some of the eggs will develop into normal tadpoles. This demonstrates __________.
that differentiated cells have retained all of their genetic potential
DNA profiles are used to determine whether Sam could be the father of Becky's baby. Sam is not the father if _____ genetic profile shows some bands not present in _____ genetic profile.
the baby's ... Sam's or Becky's
Assume you were studying two characteristics of peas, and when you crossed heterozygous F1 individuals you did not see the 9:3:3:1 ratio predicted for a dihybrid cross. You later found that these two characteristics were on the same chromosome. With this information, how would you explain the results?
the genes are linked and are inherited together
The process of accurately amplifying a sample of DNA is called __________________________.
the polymerase chain reaction
A true-breeding plant that produces yellow seeds is crossed with a true-breeding plant that produces green seeds. The seeds of all of the offspring are yellow. Why?
the yellow allele is dominant to the green allele
Sequencing the DNA of organisms such as fruit flies and yeast is useful because __________
they have many genes that are similar to those of humans
Is this true or false?: Scientists have been able to successfully produce medicines by genetic engineering.
true
Why is it that men are responsible for the gender of their children?
unlike women, who only contribute an X chromosome, men contribute either an X or a Y chromosome
RNA contains the nitrogenous base ______ instead of ______, which is only found in DNA.
uracil thymine
Archaeologists unearthed a human skull with a small dried fragment of the scalp still attached. They extracted a tiny amount of DNA from the scalp tissue. How could they obtain sufficient DNA for an analysis of the ancient human's genes?
use the polymerase chain reaction
The most common phenotype in a natural population is referred to as the __________.
wild type
Can two plants with purple flowers produce offspring with white flowers?
yes, if both parents are heterozygous for the trait