Bio 7-10
Use the DNA template strand below to synthesize a polypeptide. Write your answer in the box below. Use the one-letter amino acid abbreviations in your answer (see figure 7.7). For example, if you determine the amino acid sequence is serine-proline-lysine, type SPK as your answer. Template strand: AATACGGCC
LCR
Why do recessive X-linked traits occur more frequently and with greater severity in human males than in human females? (Select all that apply.)
Males have two Y chromosomes, so they never receive a dominant allele carried on an X chromosome. In males, X inactivation shuts off expression of the alleles on one X chromosome. Only females who inherit two X-linked recessive alleles fully express the recessive phenotype. Sperm are more likely to carry an X chromosome than a Y chromosome.
_____ is the cell division process that occurs in diploid germ cells and gives rise to haploid cells.
Meiosis
______ is a specialized type of cell division that produces cells that are genetically different from each other.
Meiosis
______ formulated key principles of genetics before DNA, genes, and chromosomes were discovered.
Mendel
Use the chromosome image, where the letters represent genes, to match the statements with their answers.
Possible genotype of resulting gamete FGrm Possible recombinant chromatid genotype rM Most likely to be separated by crossing over F and g Smallest crossover frequencyR and M Single dominant allele M Single recessive allele f
AZT is a drug that is commonly used to fight HIV infection. The active component of AZT is a nitrogenous base that mimics thymine. Normal nucleotides CANNOT covalently bond to the thymine mimic. HIV's reverse transcriptase enzyme will use the thymine mimic instead of using thymine, whereas our DNA polymerase will not make this mistake. What is the most likely explanation for how AZT prevents HIV replication?
The DNA strand produced by reverse transcriptase will stop being synthesized the first time the thymine mimic is inserted.
If a female with genotype Dd mates with a male of genotype dd, what are the possible genotypes of the haploid gametes they produce? Select all that may apply.
The female can only produce d gametes. The female can only produce D gametes. The female can produce D and d gametes.
Read Investigating Life 10.1. As indicated in the image below, the dominant allele (R) confers susceptibility to the Bt toxin, and a recessive allele (r) confers resistance to Bt. Suppose that a resistant female mates with a susceptible male. They have many offspring, the size and survival of which are shown in the graph. What is the genotype of the male parent, and what is the genotype of the susceptible offspring? (Assume complete dominance.)
The genotype of the male parent is Rr and the genotype of the susceptible offspring is Rr.
True or false: Gene regulation allows cells to produce only the proteins that they need.
True
Which are the stop codons?
UAA, UAG, UGA
The RNA product of the genetic code above has the sequence ______ It binds to the small subunit of the ________ It is joined by the large subunit, completing the initiation stage of the process of _______
UGGCGAACGGCGUUA. ribosome. translation.
Use the DNA template strand below to create a complementary RNA strand. Type the complementary RNA strand in the box. Template strand: AATACGGCC
UUAUGCCGG
About translation (a - e): What does the transfer RNA contribute to the process?
What does the transfer RNA contribute to the process?
Nondisjunction of the ______ chromosome during meiosis can produce offspring that are XXX or XXY. Multiple choice question. 21st
X
What occurs early in embryonic development of female mammals to prevent "double dosing" of proteins from X chromosomes?
X inactivation
What process in females balances the inequality of having a double dose of every gene carried on the X chromosome and leads to the expression of the paternal X allele in some cells and the maternal X allele in other cells?
X inactivation
In sexual reproduction, the sex cells of two different parents fuse to form
a genetically different offspring.
Define Transfer RNA
a molecule of RNA that binds an amino acid at one site and an mRNA codon at its anticodon site
Define Ribosomal RNA:
a molecule of RNA that, along with proteins, forms a ribosome
Select the two characteristics that all viruses share.
a protein coat that surrounds the genetic material genetic material, either RNA or DNA
Define gene
a segment of DNA that codes for a protein or RNA molecule
A chromosome is a(n) ______.
a single molecule of DNA and its associated proteins
Define ribosome:
a structure built of RNA and protein where mRNA anchors during protein synthesis
About codon. (a - e) Define codon.
a three base mRNA sequence that codes for ONE amino acid. The term is also used for a DNA bases triplet on the non-template strand. As codons are triplets of bases, the number of nucleotides that make up the genetic message must be three times the number of amino acids specified in the protein. mRNA.
Define Messenger RNA:
a type of RNA that transcribes the genetic code of a DNA molecule
According to the image below, a mutation in a gene is analogous to
a typo in a recipe.
Define genome:
all the genetic information in a cell
A variant of a gene is referred to as a(n)
allele.
A gene has different versions, or _____ , which are carried on homologous chromosomes and encode different versions of the gene's protein product.
alleles
Alternative forms of a gene are called
alleles
Different varieties of the same gene, called ______, may arise from mutations.
alleles
What are different versions of a gene?
alleles
On a tRNA molecule, the is a three-base sequence that is complementary to and binds to an mRNA codon during translation.
anticodon
What three-base site of a tRNA molecule is complementary to an mRNA codon?
anticodon
n animals, an intentional, programmed death of some cells occurs through a process called ______.
apoptosis
When ______ reproduction occurs in a one-celled organism, the organism replicates its DNA and splits into two genetically identical cells.
asexual
Binary fission is a type of ______ seen in prokaryotes, such as archaea and bacteria. asexual reproduction sexual reproduction gamete formation colonial aggregation
asexual reproduction
New viral particles ____
assemble
Rank the five steps of viral replication in the order in which they occur during an infection, beginning with the first step at the top.
attachment to host cell penetration synthesis of viral components assembly of new viruses release of new viruses from host cell
Select all of the following that are methods of gene regulation found in eukaryotes but not prokaryotes.
blocking mRNA exit from the nucleus splicing exons in alternative ways adding methyl groups to silence genes
Select all the examples of cells that divide constantly to produce new cells. Multiple select question. bone marrow stem cells mature brain cells mature skin cells cells at the tips of plant roots
bone marrow stem cells cells at the tips of plant roots
Genes A, B, C, and D are linked. The crossover frequency between the genes in each column and row are listed in the table below. Use the table to determine the order of the genes. Click on the one correct answer.
c-a-b-d
After a virus attaches to and penetrates a host cell, a virus can enter a phase where symptoms of the infection are delayed or it can
cause immediate cell death.
A single nucleotide deletion during DNA replication
causes the amino acids encoded by nucleotides after the deletion to be incorrect.
The ______ describes the series of events that occur in a eukaryotic cell from cell division, including division of the genetic material and the cytoplasm, through the interval of cell activity before the next cell division.
cell cycle
Several internal ______ in the cell cycle ensure that a cell does not enter into the next phase of the cell cycle before completing the previous phase.
checkpoints
Select all of the cancer therapies that are considered to be "blunt tools" because they target rapidly dividing cells, regardless if they are healthy or cancerous. chemotherapy surgical removal radiation
chemotherapy radiation
A replicated chromosome consists of two attached copies called sister .
chromatids or chromatid
Eukaryotic chromosomes consist of _______, which is composed of uncondensed DNA and associated proteins.
chromatin
In eukaryotes, a molecule of genetic material and its associated proteins form a(n) _____, of which humans have 46 in each cell.
chromosome
A single molecule of DNA and its associated proteins is called a
chromosome.
In the nucleus of eukaryotic cells, all of the DNA is divided into multiple , which are continuous, long strands of DNA wrapped around proteins.
chromosomes
Long strands of DNA and their associated proteins are called
chromosomes
Short segments of DNA are exchanged between homologous chromosomes during prophase I in a process called________over.
chromosomes can orient
A cell's genetic material is contained in one or more
chromosomes.
Each mRNA 3-base sequence, called a -------matches with a tRNA sequence called the --------. The tRNA also carries the specified amino acid, used as a building block for a protein.
codon,anticodon amino acid,
Select all that apply Select all of the following that are true about autosomal recessive inheritance of a human disorder.
Both parents of an affected individual carry at least one copy of the disease-causing allele. Heterozygous individuals are called carriers.
Select all of the following that are true about cancer risk. Multiple select question. Chemicals or radiation in the environment can cause mutations that lead to cancer. Genetic mutations can cause cancer. Mutated genes that cause cancer can be inherited. Cancer only arises as spontaneous mutations and cannot be inherited. Cancer risk increases with age. A poor diet does not affect cancer risks.
Chemicals or radiation in the environment can cause mutations that lead to cancer. Genetic mutations can cause cancer. Mutated genes that cause cancer can be inherited. Cancer risk increases with age.
Match each type of RNA to its correct description. tRNA rRNA mRNA
Combines with proteins to form a ribosom--- rRNA Carries amino acids to ribosomes and binds to codons --tRNA Its codons specify the order of amino acids in translation--mRNA
Following mitosis, what process splits the organelles, cytoplasm, duplicated nuclei, and macromolecules into two daughter cells?
Cytokinesis
The instructions in ______ encode the information that a cell needs to produce proteins, which are vital to living things.
DNA
During the elongation stage of translation, a _______ bond is formed between the incoming _______ acid and the growing polypeptide chain, and empty tRNAs are released from the ribosome.
covalent; amino
Select all the possible results of nondisjunction in sex chromosomes.
gamete is missing a sex chromosome gamete contains an extra X gamete contains an extra Y XXX zygote
The haploid cells of humans are called
gametes
Adults produce haploid _________through the process of --------
gametes meiosis.
The special haploid cells required for sexual reproduction are called
gametes.
A(n) ______ is a portion of DNA that encodes a protein.
gene
Crossing over, random orientation of chromosomes, and random fertilization are mechanisms involved in meiosis and sexual reproduction that generate _________diversity.
genetic
The chromosomes of offspring are not identical to those of their parents or siblings because ______ is shuffled during meiosis.
genetic information
A cell's _____is defined as all the cell's genetic material (DNA) and consists of one or more chromosomes containing the DNA.
genome
A cell's ____is defined as all the cell's genetic material (DNA) and consists of one or more chromosomes containing the DNA.
genome
In order for a eukaryotic or prokaryotic cell to divide, it needs to first duplicate its entire ______, which consists of all of its genetic material. Multiple choice question. membrane
genome
An individual's allele combination for a particular gene is called the .
genotype
The genetic makeup of an individual is called the
genotype
Daughter cells produced in meiosis have
half the number of chromosomes as daughter cells produced in mitosis
A(n) ______ cell contains only one copy of each chromosome.
haploid
The abbreviation n or 1n represents a_____________ cell.
haploid
n transcription, the genetic information in DNA is copied into a(n) ______ molecule, and in translation, the "message" in an mRNA molecule is translated into a(n) ______ sequence. Multiple choice question. protein; tRNA
mRNA; amino acid
X-linked recessive disorders can affect more human males than females because ______ always express the disorder when they inherit the recessive allele from ______. Multiple choice question.
males; the mother
Cell division that results in the production of gametes is called
meiosis
What process gives rise to gametes in humans?
meiosis
A cell in which homologous chromosomes arrange in pairs along the equator of the cell is in what stage of cell division?
meiosis I
Dividing cells that contain only one chromosome from each homologous pair aligned at the equator of the cell must be undergoing
meiosis II.
During what phase of meiosis I does the spindle arrange the homologous pairs of chromosomes along the equator of the cell?
metaphase I
Random orientation of homologous chromosomes occurs in ________ of meiosis.
metaphase I
The mitotic spindle is composed of protein fibers called ______ that coordinate the movements of ______ during mitosis.
microtubules; chromosomes
Centromeres divide in
mitosis and meiosis II
A type of cell division, called ---------now occurs rapidly as the embryo develops. Some events of development also require programmed cell death, or ----------
mitosis apoptosis.
Eukaryotic cells produce new cells for growth and repair through a cell division process known as
mitosis.
Define amino acid:
molecules that combine to form proteins. Amino acids and proteins are the building blocks of life.
A ______ cross is a mating between two individuals that are both heterozygous for the same, single gene.
monohybrid
An example of a(n) ______ cross is the mating of two rats that both contain the alleles Ff for fur color. This cross is made to examine which of two fur colors their offspring will have.
monohybrid
Define nucleotide
monomer of nucleic acid
A(n) is any external agent, such as X-rays or chemicals, that induces mutations.
mutagen
UV rays, X-rays, some chemicals found in tobacco, and radioactive fallout are all examples of _____, agents that can damage DNA and cause mutations.
mutagens
A change in a gene sequence or a regulatory DNA sequence is called a(n) ______.
mutation
A(n) is a change in a cell's DNA sequence.
mutation
A process called ______ is an error in meiosis in which chromosomes fail to separate and a gamete with too many or too few copies of a particular chromosome can be produced.
nondisjunction
A DNA molecule consists of two strands of ______ held together in a ______ structure. Multiple choice question. nucleotides; cloverleaf nucleotides; double helix amino acids; globular amino acids; helix
nucleotides; double helix
What describes a substitution mutation?
one DNA base is replaced with another
A type of gene expression called pleiotropy occurs when
one gene has multiple effects on the phenotype.
What describes the product of DNA replication?
one strand of a new DNA double helix is newly synthesized and the other strand is from the parent molecule.
Select all of the following that are present in a bacterial operon.
operator group of genes promoter
In bacteria, a(n) ______ is a group of genes under control of a single promoter.
operon
The 2 meters of DNA that makes up the human genome is able to fit in one cell because the chromatin is ______.
organized around proteins
What occurs during meiosis but not mitosis?
pairing of homologous chromosomes
The viral nucleic acids --------the host cells.
penetrate
Tobacco mosaic virus (TMV) infects many species of
plants
Analyze the image below, which shows one protein affecting three biochemical pathways. Then, click on the term that best describes how the gene encoding this protein affects the phenotypes of the individual.
pleiotropy
In ______, one gene encodes a protein that is important in many biochemical pathways or that affects many parts of the body.
pleiotropy
Human eye color is controlled by multiple enzymes encoded by multiple genes; therefore, human eye color is an ______ trait.
polygenic
If the phenotype reflects the activities of more than one gene, it is called a ______ trait.
polygenic
RNA ______ is the enzyme that builds the RNA chain during transcription.
polymerase
The enzyme called DNA ______ adds new complementary DNA nucleotides to a single-stranded DNA template.
polymerase
About translation (a - e): What type of molecule is the final product?
polypeptides
Classify the following phrases as related to mitosis or meiosis. If it relates to both, then place the label in the "both" dock. Some labels may not be used.
presence of living bacteria
The _____rule states that the chance of two independent events occurring is equal to the product of the individual chances that each event will occur.
product
If a couple that are both heterozygous carriers of the cystic fibrosis allele have children, the chance that both their first and their second child are carriers is 0.5 x 0.5, or 25%, as determined by the
product rule.
At the beginning of transcription, RNA polymerase binds to the ______ on the DNA.
promoter
The ______ is a sequence of DNA that signals the start of a gene and also which of the two strands of DNA is the template for transcription
promoter
Click and drag on elements in order Rank the steps of meiosis I in the order in which they occur, beginning with the first phase at the top. Instructions prophase I telophase I metaphase I anaphase I
prophase I metaphase I anaphase I telophase I
Crossing over only occurs in
prophase I of meiosis.
Rank the steps of meiosis II in the correct order in which they occur, beginning with the first step at the top.
prophase II metaphase II anaphase II telophase II
What role does DNA play in the cell?
store instructions for making proteins
The replacement of one DNA base with another is called a(n)
substitution mutation.
About translation (a - e):Which molecule contains an anticodon?
tRNA molecule
The gene sequence above undergoes ___to produce------with the help of RNA polymerase, and other proteins. This occurs in the ------of a eukaryotic cell.
transcription mRNA nucleus
Select all of the following that can result from nondisjunction in humans.
trisomy an extra copy of a chromosome failed development due to missing genetic material
Both somatic cells and germ cells are diploid, although only germ cells can undergo meiosis.
true
Chromosome duplication occurs prior to both mitosis and meiosis.
true
Crossing over occurs during prophase I of meiosis.
true
A ______ organism always produces offspring that are identical to the parent when self-fertilized.
true-breeding
Sometimes, loss of control over cell division results in a ____, an abnormal mass of tissue.
tumor
How many rounds of cell division occur in meiosis?
two
If crossing over occurs only between the two alleles of the same gene, as shown in the animation, what allele combinations are present in the gametes?
two gametes with parental combinations of alleles, and two recombinant gametes
elect all of the following that are true about sexual reproduction.
two parents are required offspring are genetically different from each other offspring are genetically different from their parents
Select all that apply Select all of the following that describe the inheritance of an autosomal dominant disorder.
typically present in every generation expressed in homozygous dominant individuals and heterozygous individuals
Attachment, penetration, synthesis, assembly, and release are the stages of
viral replication.
A ________attaches to a host cell by adhering to surface ________ on host cells.
virus receptors
A small, infectious agent that is composed of genetic information inside of a protein coat is a called a
virus.
Can there be more than one codon for the same amino acid?
yes
The first diploid cell of a new organism, called a(n) , has a set of chromosomes from each parent.
zygote
The diploid cell created from the fusion of gametes is called a(n)
zygote.
Define protein
~ Proteins are large macromolecules consisting of more than one amino acid chain
______ are haploid sex cells which combine to form new offspring.
Gametes
How are "gamete," "chromosomes," and "zygote" related?
Gametes unite, forming zygotes with two sets of chromosomes.
What is a sequence of DNA nucleotides that holds the instructions to make a protein?
Gene
Who discovered the basic principles of inheritance using traits of pea plants?
Gregor Mendel
Which pairs with cytosine?
Guanine
What is the genotype of the right-most individual in row II?
Homozygous dominant
When is the DNA in chromosomes replicated?
Interphase
What is wrong with the following piece of mRNA? TACCAGGATCACTTTGCCA
It contains T and not U.
Why is DNA called a double helix?
It has two strands that are shaped into a spiral.
What is the first set of individuals mated in a particular cross?
P generation
Define chromosome:
Packaged DNA molecule.
In a genetic cross, what does the P generation represent?
Parental generation
What type of cells may divide constantly throughout their life?
stem cells
In what type of bacteriophage infection does the host cell burst open, releasing the new viral particles?
Blank 1: virus or virion
About transcription (a - h) What is the starting molecule?
. The process of transcription begins when an enzyme called RNA polymerase (RNA pol) attaches to the template DNA strand and begins to catalyze production of complementary RNA.
Suppose the second male from the left in row III had a child with the female on the far right side of row III. What percentage of their offspring will be affected?
0%
A pea plant is heterozygous for the genes for seed form (Rr) and seed color (Gg). It is crossed with a pea plant of the genotype rrgg. How many of the 60 offspring of this mating are predicted to show the dominant trait for both genes? (The genes are not linked.)
15
A cell that has four pairs of chromosomes is undergoing meiosis. What is the number of possible chromosome combinations in the gametes produced by that cell?
16
Arrange the following events in the proper order in which they occur during meiosis I.1 = Separation of homologous chromosomes2 = Coming together of homologous chromosomes3 = Crossing-over4 = Random orientation of homologous chromosomes at cell equator
2341
A diploid cell is indicated by what abbreviation?
2n
How many bases make up one codon?
3 bases
The Punnett square below represents a cross between two parents that are heterozygous for the F gene. What percentage of the offspring are predicted to be heterozygous for the F gene?
50%
If an animal has 6 chromosome pairs in its cells, then 64 combinations of chromatids are possible for a gamete. If both male and female gametes have 64 possible chromosome combinations, how many genetically unique zygotes could be produced due to random fertilization? (Assume crossing over does not occur.)
About 4,000
What are the four nucleotide bases found in DNA?
Adenine, Thymine, Guanine, Cytosine
Put the following events of translational elongation (the stage in translation that occurs after initiation) in the order that they occur, beginning with the first step at the top.
After the first amino acid has been brought to the ribosome, a tRNA carrying the second amino acid of a protein binds to the second codon. A covalent bond forms between the first and second amino acids. The ribosome releases the first tRNA. The ribosome moves down the mRNA by one codon, and a tRNA carrying the third amino acid comes into place. A covalent bond forms between the second and third a mino acids. The ribosome releases the second tRNA.
What type of reproduction produces offspring that are identical to the parent (except for mutations)?
Asexual
What is the inheritance pattern of the disorder shown in the pedigree?
Autosomal recessive
Although Mendel did not know that random orientation of homologous chromosome pairs during metaphase I leads to random allele combinations of different genes in gametes, he created the law of ______, ______which deduced this phenomenon.
Blank 1: independent Blank 2: assortment
During , ---=----the information that is encoded in the DNA base sequence is copied into the complementary language of mRNA. Then, once the mRNA is produced and modified, a process called-----uses that information to assemble a sequence of amino acids.
Blank 1: transcription Blank 2: translation
In the "central dogma" describing the flow of genetic information from DNA to protein, DNA is copied to RNA in a process called ,------ and the information in RNA is used to direct the synthesis of a protein in a process called ------
Blank 1: transcription Blank 2: translation
Where in the cell cycle is DNA polymerase most active?
DNA polymerase is active during DNA replication, which occurs during S phase.
In ______, two DNA double helices are synthesized from one DNA double helix molecule when it unwinds and complementary nucleotides are added to the exposed unpaired bases.
DNA replication
In order for a cell to divide, all of its genetic information has to be duplicated through a process called
DNA replication.
The process of reading a DNA strand and making a complementary DNA copy of that strand is called
DNA replication.
All viruses contain genetic material, which is either RNA or ______, and a(n) ______ coat that surrounds the genetic material.
DNA; protein
How are diploid cells, homologous chromosomes, and alleles related?
Diploid cells have homologous pairs of chromosomes, which carry the same genes as one another but not necessarily the same alleles.
Select all of the following that can result from nondisjunction of the X chromosome.
Down syndrome polyploidy polyploidy Correct an XYY male an XYY male Correct an XXX female
About transcription (a - h) What is an intron? What happens to introns?
During transcription, the entire gene is copied into a pre-mRNA, which includes exons and introns. During the process of RNA splicing, introns are removed and exons joined to form a contiguous coding sequence. This "mature" mRNA is ready for translation.
About transcription (a - h) What is an exon?
Exons are nucleotide sequences in DNA and RNA that are conserved in the creation of mature RNA. The process by which DNA is used as a template to create mRNA is called transcription.
Select all of the following that act as controls of cell division. DNA ligase External growth factors Mitotic spindle Cell cycle checkpoints
External growth factors Cell cycle checkpoints
In a frameshift mutation, all of the amino acids before the shift are changed.
False
True or false: The phase of the cell cycle called interphase is a time of inactivity and rest for the cell after mitosis. True false question.True
False
______ is the merging of a sperm and an egg to create a diploid zygote.
Fertilization
Consider the types of mutations and the circumstances in which mutations arise to select those TRUE statements below. (Select all that apply.)
Mutagens and meiosis are two sources of mutation. A single-base insertion is usually more harmful than a single-base substitution. Mutations can be useful to the organism.
________ provides the raw material for evolution because it can create new alleles, which are alternative forms of the same ______.
Mutation; gene
What occurs when chromosomes do not separate during meiotic divisions?
Nondisjunction
What produces gametes with a missing or extra chromosome and may result in embryonic, fetal, or infant death or a trisomic individual? Multiple choice question. Point mutation
Nondisjunction
Select all of the reasons that gene regulation is advantageous in multicellular eukaryotic organisms.
Not all cells need all proteins encoded in the genome. It saves energy.
Select all of the following that occur in prophase I of meiosis. Multiple select question. DNA replicates. Nuclear envelope breaks up. Chromosomes condense. Crossing over occurs. Sister chromatids separate. Spindle forms from microtubules.
Nuclear envelope breaks up. Chromosomes condense. Crossing over occurs. Spindle forms from microtubules.
lect the stages of the cell cycle during which each chromosome consists of two chromatids joined at the centromere.
Prophase Late interphase Metaphase
About transcription (a - h) What is the poly A tail?
RNA
During transcription, what reads the template strand within a gene and adds complementary bases?
RNA polymerase
About transcription (a - h) What does RNA polymerase do?
RNA polymerase builds an RNA strand in the 5' to 3' direction, adding each new nucleotide to the 3' end of the strand.
Random orientation of chromosome pairs during metaphase I
Random orientation of chromosome pairs during metaphase I
Suppose the second male from the left in row III had a child with the female on the far right side of row III. What percentage of their offspring will be affected?
Seven
What statement correctly describes the result of the experiment discussed in the Investigating Life feature?
Sexual reproduction increased in roundworms exposed to live disease-causing bacteria.
A woman who is heterozygous for the X-linked, recessive hemophilia allele mates with a man who does not have hemophilia. Which of the possible offspring will have hemophilia?
Son: one X chromosome carrying the recessive hemophilia allele and one Y chromosome
Replication creates a complementary strand of DNA. Given the following parental strand of DNA, what would be the nucleotide sequence of the daughter strand?
TTGACCGTAGCTGATCCC
Select all of the following that are true regarding nondisjunction and trisomy 21 (Down syndrome).
The older the mother, the higher the chances of producing a child with Down syndrome. Nondisjunction during sperm production can lead to sperm gametes with abnormal numbers of chromosomes.
Why might it be advantageous for bacteria to prevent transcription of a particular enzyme, unless its substrate is present in the environment?
The steps involved in synthesizing proteins such as enzymes require a considerable amount of energy.
Which of the following best describes the overall process of mitosis?
The type of cell division that separates chromosomes and produces two daughter cells with identical nuclei.
Select all of the following that are true about malignant tumors. Multiple select question. They are likely to metastasize. They are surrounded by a tough capsule. They invade adjacent tissue.
They are likely to metastasize. They invade adjacent tissue
Which nucleotide base pairs with adenine?
Thymine
A TATA box and a terminator sequence would apply to what part of the diagram?
Transcription
Select all the body and cellular processes that require cell division (mitosis or meiosis) to function.
Translatiogrowth dead cell replacement reproductionn
The resulting portion of the polypeptide has this sequence (using the 3-letter codes):
Trp-Arg-Thr-Ala-Leu.
Select all of the following that are true about meiosis. doubles the genetic information in the resulting gamete cells produced creates four haploid cells from one diploid cell includes two cell divisions creates four genetically identical gametes produces gametes with half the number of chromosomes as compared to somatic cells
creates four haploid cells from one diploid cell includes two cell divisions produces gametes with half the number of chromosomes as compared to somatic cells
Select all of the mechanisms that generate genetic variability in sexual organisms.
crossing over random orientation of chromosomes random fertilization
In prophase I, allele shuffling between homologous chromosomes occurs in a process called
crossing over.
What cellular event is occurring in this picture? Multiple choice question. S phase G2 phase cytokinesis interphase
cytokinesis
An example of a(n) ______ cross is the mating of two rats that both have the genotype Ff Tt for fur color and tail length to examine which of two fur colors and tail lengths their offspring will have.
dihybrid
What type of cross is a mating between two individuals that are both heterozygous for the same two genes?
dihybrid cross
A cell with two complete sets of chromosomes is a ____ cell.
diploid
A human ______ cell has 46 chromosomes, 23 chromosomes from each parent.
diploid
A(n) ______ cell contains two sets of chromosomes, one set of chromosomes inherited from each parent.
diploid
The gametes of humans are called
eggs and sperm
Transcription, translation, nucleotide synthesis, and modification of mRNA are all processes that require
energy.
Siamese cats and Himalayan rabbits have light-colored bodies but darker-colored paws, ears, and tail due to an enzyme whose activity varies with temperature. This is an example of ______.
environmental effects
The effect of diet and lifestyle choices on phenotypes in humans is an example of
environmental effects.
Germ cells are haploid but gametes are diploid.
false
Mitosis and meiosis II are similar, except that cells undergoing meiosis II are diploid and cells undergoing mitosis are haploid.
false
Only germ cells have sex chromosomes.
false
Tue or false: The daughter cells of mitosis have half as many chromosomes as the parent cell. True false question.True
false
X inactivation occurs early in ______ embryonic development and prevents ______ of every gene on the X chromosome.
female; a double dose
X inactivation occurs early in ______ embryonic development and prevents ______ of every gene on the X chromosome. Multiple choice question. female; a double dose
female; a double dose
The union of these cells occurs during ______, forming a ________
fertilization, zygote
What process occurs when gametes from two parents fuse?
fertizlizatoin
Binary ______ is a type of prokaryotic asexual reproduction in which replicated DNA and other cell parts are distributed into two new daughter cells.
fission
After translation is complete, the newly synthesized protein must ______, as determined by some regions of the amino acid chain.
fold into its functional shape
About translation (a - e): What does the ribosome contribute to the process?
he ribosome is responsible for translating encoded messages from messenger RNA molecules to synthesize proteins from amino acids. The ribosome translates each codon, or set of three nucleotides, of the mRNA template and matches it with the appropriate amino acid in a process called translation.
A(n) ______ individual has 2 different alleles for a given gene.
heterozygous
If parents contribute different versions of a gene, then the offspring are ______ for that gene.
heterozygous
To help fit the very long molecules of DNA that compose a eukaryotic genome into the nucleus of a cell, stretches of DNA are wrapped around proteins called ______.
histones
Two chromosomes with the same size, centromere location, and gene sequence are called a(n) _________pair.
homologous
Crossing over is the process in which ______.
homologous chromosomes physically exchange pieces.
A crossover in meiosis is an exchange of genetic material between
homologous chromosomes.
Two matching chromosomes having the same basic structure and same sequence of genes are called a ______.
homologous pair
A ______ individual has two identical alleles for a gene.
homozygous
f both parents contribute identical versions of a gene, then the offspring are ______ for that gene.
homozygous
A ______ organism produces mixed offspring: some that are identical to the parent plant and some that are different.
hybrid
In a DNA molecule, ______ bonds form between nitrogenous bases, such that A (adenine) pairs with its complement ______, and G (guanine) pairs with its complement ______.
hydrogen; T (thymine); C (cytosine)
Multiple Choice Question In asexual reproduction, the offspring are genetically ________ to each other.
identical
In a gene expression pattern called ______, the heterozygote has an intermediate phenotype between the homozygotes.
incomplete dominance
The pedigree shows the detail of Bt resistance in three generations of Bollworms. The square represents male, while the circle represents female. The Bt susceptible individuals are fully black in colour, while the normal are colourless. The first generation shows a cross between a normal male and female. The second generation consists of two susceptible male and one female, a normal male, and two normal females. The third generation shows two susceptible males and one female, and three normal males and one female.
incomplete dominance
The pink snapdragon flowers in the picture are an example of
incomplete dominance.
Select all that apply Select all of the following that can increase the risk of cancer.
increased age sexually transmitted viruses UV radiation smoking
The picture of gamete production with two genes uninfluenced by each other as they are divided in meiosis I and II supports Mendel's law of
independent assortment.
During a section of the cell cycle collectively called ______, the cell is not dividing, but protein synthesis, cell growth, DNA replication, and basic cell functions are occurring.
interphase
A(n) is a portion of mRNA that is about 1,000 nucleotides long and that is removed before translation.
intron or introns
In archaea and eukaryotes, a part of an mRNA molecule that is removed before translation is called a(n)
intron.
A malignant tumor is one that
invades surrounding tissue.
This diagram of gamete production from meiosis and gamete fusion in fertilization supports Mendel's ______.
law of segregation
In the ______ infection cycle, a bacteriophage replicates and then causes the host cell to burst, thus killing it and releasing the new viral particles.
lytic
Select all of the following that are features of both mitosis and meiosis. Multiple select question. prophase, metaphase, anaphase, and telophase steps preceded by interphase crossing over and random alignment produce diploid cells spindle fibers made of microtubule proteins
prophase, metaphase, anaphase, and telophase steps preceded by interphase spindle fibers made of microtubule proteins
Enzymes and chaperone proteins assist in ______ that takes place after translation is complete.
protein folding
If the genes encoding any of these ___have mutations, then cells might receive improper signals to divide.
proteins
In the "central dogma," information flows from DNA to RNA to ______.
proteins
Some ______ are chemical signals that regulate the cell cycle by stimulating cell division.
proteins
Select all that apply Select all of the following that are components of chromatin. Multiple select question. spindle microtubules centrosomes proteins for replication proteins for scaffolding DNA proteins for transcription
proteins for replication proteins for scaffolding DNA proteins for transcription
When these ------- bind to ---------- on a cell membrane, they initiate a cascade of reactions that results in___
proteins receptor proteins
Transcription and translation produce ____ using the information in genes.
proteins,genes
In sexual reproduction, exactly what egg cell matures and what sperm cell fertilizes the egg is
random and results in genetic variability.
The host cells _____he new viruses.
release
The host cells _____ the viral _______and produce viral proteins.
replicate genomes
Select all of the following that take place during interphase preceding meiosis.
replication of DNA synthesis of proteins and enzymes needed for cell division production of two identical sister chromatids attached at the centromere
Some method of cell division is necessary for every organism to
reproduce.
Only producing proteins that are needed allows a cell to
save energy.
Although Mendel did not know that homologous chromosomes separate during meiosis I such that the alleles of one gene are packaged into separate gametes, he developed the law of ______, which deduced this phenomenon.
segregation
In a human karyotype________, there are 22 pairs of autosomes and 1 pair of chromosomes.
sex
The ______ are the genetic components that determine whether a mammal develops as a male or female.
sex chromosomes
Genes that are located on the X or Y chromosome are said to be ______ and often are expressed in one sex more than the other.
sex-linked
Red-green color blindness and hemophilia are examples of ______, which are controlled by alleles on the sex chromosomes.
sex-linked genes
After DNA replication, chromosomes consist of two
sister chromatids
In meiosis I, homologous chromosomes separate, whereas in meiosis II,
sister chromatids separate.
A mutation in a gene would ______cause a change in the sequence of amino acids in a protein.
sometimes
The _______ consists of microtubule fibers that move the chromosomes during mitosis.
spindle
Select all that apply Select all of the processes involved in asexual reproduction.
splitting of one cell into two cells replication of the genetic material
Why are the DNA strands called complementary to each other?
the bases from one strand consistently paired on its match bases on the opposite strand (ex. A=T). With this, each DNA strand has the necessary information to make a copy of the other DNA strand.
The nucleotide sequence in mRNA is determined by
the nucleotide sequence in DNA.
Complete this sentence: If the nucleotides ATT were inserted into the template strand of a gene, then
the resulting protein will be shorter and nonfunctional.
A latent viral infection is one in which
the viral genetic information remains inside the cell but does not cause disease symptoms.
The first virus ever discovered was ______, a virus that infects over 120 plant species.
tobacco mosaic virus
Gene expression step - simple Is transcription or translation shown in the image below?
transcription
In eukaryotic cells, proteins called ______ factors bind at specific DNA sequences and form a pocket that allows RNA polymerase to initiate transcription.
transcription
In eukaryotes, RNA polymerase cannot bind to the promoter and initiate transcription without the presence of regulatory proteins called Multiple choice question. repressors.
transcription factors.
n eukaryotes, RNA polymerase cannot bind to the promoter and initiate transcription without the presence of regulatory proteins called Multiple choice question. operators.
transcription factors.
