50 terms

Bio Multiple Choice

Crossing over ______ genes into assortments of _____not found in the parents
recombines linked...alleles
The chromosome theory of inheritance states that
the behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance
Imagine that beak color in a finch species is controlled by a single gene. You mate a finch homozygous for orange(pigmented) beak with a finch homozygous for ivory(unpigmented) beak and get numerous offspring, all of which have pale, ivory-orange beak. This pattern of color expression is most likely to be an example of
incomplete dominance
Which of the following is essentially the opposite of pleiotropy?
polygenic inheritance
which of the following statements regarding cross-breeding and hybridization is FALSE?
the hybrid offspring of a cross are the P1 generation
If A is dominant to a, and B is dominant to b, what is the expected phenotypic ratio of the cross: AaBb*AaBb
Imagine that we mate two black labrador dogs with normal vision and find that three of the puppies are like the parents, but one puppy is chocolate with normal vision and another is black with PRA( a vision disease) We conclude that
the alleles for color and vision segregate independently during gamete formation
Genes located together on the same chromosomes are referred to as ____ genes and generally _____
linked....do not sort independently during meiosis
the mechanism that "breaks" the linkage between linked genes is
crossing over
The sex chromosome complement of a normal human female is
Recessive X-linked traits are more likely to be expressed in a male fruit fly than a female fruit fly because
the males phenotype results entirely from his single X-linked gene
for most sexually reproducing organisms, Mendel's laws
cannot strictly account for the patterns of inheritance of many traits
Linked genes generally
do not follow the laws of independent assortment
sex-linked conditions are more common in men than in women because
men need to inherit only one copy of the recessive allele for the condition to be fully expressed
All the offspring of a cross between a black eyed mendelien and an orange eyed mendelien have black eyes. What is the expected phenotypic ratio of a cross between two orange eyed mendeliens?
0 black eyed: 1 orange eyed
How is sex determined in most ants and bees?
by the number of chromosomes
Which of the following statements about ribosomes is FALSE?
The ribosomes of prokaryotes and eukaryotes are the same in structure and function
Experiments have demonstrated that the "words" of the genetic code(the units that specify amino acids) are
three-nucleotide sequences
The shape of a DNA molecule is most like
a twisted rope ladder
A protein coat enclosing a viral genome is known as a(n)
In the genetic code,
many amino acids are specified by more than one codon
which of the following enzymes does HIV use to synthesize DNA on an RNA template?
reverse transcriptase
The mRNA sequence AUCUAAGGC undergoes a mutation and becomes AUCUUUGGC. This is a ______ mutation.
In the 1920's Frederick Griffin conducted an experiment in which he mixed the dead cells of a bacterial strain that can cause pneumonia with live cells of a bacterial strain that cannot. When he cultured the live cells, some of the daughter colonies proved able to cause pneumonia. Which of the following processes of bacterial DNA transfer does this experiment demonstrate?
HIV does the greatest damage to
white blood cells
Multiple origins of replication on the DNA molecules of eukaryotic cells serve to
shorten the time necessary for DNA replication
A physical or chemical agent that changed the nucleotide sequence of DNA is called a(n)
The mRNA sequence AUCCACGGC undergoes a mutation and becomes AUCCAGGC. This is a _____ mutation
frameshift and missense
DNA replication
uses each strand of a DNA molecule as a template for the creation of a new strand
When one DNA molecule is copied to make two DNA molecules, the new DNA contains
50% of the parent DNA
Which of the following enzymes catalyzes the linking together of RNA nucleotides to form RNA?
RNA polymerase
The enzyme that assists mRNA nucleotides in finding their complementary DNA is
RNA polymerase
Which of the following statements about eukaryotic RNA is TRUE?
A) A small cap of extra nucleotides is added to both ends of the RNA
B)The modified RNA molecule is transported into the nucleus
C) Introns are added to the RNA
D)Exons are spliced together
exons are spliced together
Which of the following statements regarding RNA is FALSE?
A) RNA uses the nitrogenous base uracil
B) One RNA molecule can include four different nucleotides in its structure
C) RNA molecules have a sugar-phosphate backbone
D)RNA uses the sugar dextrose
RNA uses sugar dextrose
Which of the following statements regarding a DNA double helix is ALWAYS TRUE?
The amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine
The enzyme that unwinds and stabilizes DNA during replication is
Which of the following statements about herpesvirus is FALSE?
herpesvirus reproduce inside the host cell's mitochondria
Where do transcription and translation occur in prokaryotic cells?
in the cytoplasm
In the _______ cycle of viral replication, prophages are formed until an environmental trigger arises
Why does a DNA strand grow only grow in the 5' to 3' direction?
because DNA polymerases can only add nucleotides to the 3' end of the growing molecule
Which of the following permits a single gene to code for more than one polypeptide?
alternative RNA splicing
bind to DNA sequences and inhibit the start of transcription
Transcription factors are used during __________ gene expresssion and attach to________.
eukaryotic; DNA
RNA splicing involves the
removal of introns from the molecule
The coding regions of a gene (the portions that are expressed as polypeptide sequences) are called
The inactive X in each cell of a female condenses into a small object called a
Barr body
The round proteins that DNA coils around as it condenses into chromosomes are called
When researchers inject microRNA into a cell to turn off expression of a certain gene with a sequence that matches the microRNA, the process is called
RNA interference
Active proteins have tertiary and quaternary structure to them because there are linkages between
the sulfur atoms of amino acids.
Is this diagram showing gene regulation in a prokaryote or eukarote? Is there lactose present in the environment? Is transcription occuring?
prokaryote; no; no