Biology Exam 2
Epigenetics is translated as
"above the genome"
Based on the gel run in lab and lab discussion, a person with MSUD will have how many bands for this gene?
1
Place the steps of DNA transcription in the order in which they occur.
1. The RNA polymerase attaches to the DNA strand upstream from a gene 2. RNA bases are paired with the DNA bases on the template strand by RNA polymerase 3. The RNA breaks away from the RNA polymerase, and they both leave the DNA strand
Based on the gel run in lab and lab discussion, a person without MSUD (and not a carrier) will have how many bands for this gene?
2
Mitosis end result
2 identical cells, diploid cells
Only ___________ different amino acids can form ___________ proteins.
20...thousands
Human somatic cells contain 46 total chromosomes. How many chromosomes would a human sperm cell contain?
23 total
Emma and Jacob are both heterozygous for MSUD. What art the chances that their next child will have MSUD?
25%
Based on the gel run in lab and lab discussion, a person heterozygous for MSUD will have how many bands for this gene?
3
Meiosis end result
4 different cells, haploid cells
How many chromosomes are present in your somatic cells?
46
Communication Protein
A membrane receptor protein binds to a signaling molecule sent from a neighboring cell
Recognition Protein
A pair of liver cells identity one another using cadherin membrane proteins
A restriction enzyme acts like a
A pair of scissors
Structural Protein
A peripheral membrane protein attaches to the network of proteins surrounding the cell
What happens during the initiation step of DNA transcription?
A portion of the DNA unwinds and RNA polymerase attaches to the DNA within the transcription bubble.
Transport Protein
A potassium pump protein uses ATP to move ions across the plasma membrane against their concentration gradient
After an mRNA strand has been transcribed from DNA, it must be processed before translation can take place. Which of the following statements are true about the RNA editing process?
A tail is added to one end of the mRNA molecule and Introns are removed and coding segments are joined.
Passive Transport does not require?
ATP
Which mRNA codon functions as the start codon, directing the ribosome to begin translating the mRNA from the correct end?
AUG
The inheritance pattern for sheep coat color exhibits incomplete dominance. A sheep that is homozygous for the black allele is crossed with a sheep that is homozygous for the white allele. What is the phenotypic outcome of the offspring that result from this cross?
All offspring have gray coats.
Identify the statement that defines an individual who is heterozyous for a gene.
An individual inherits two different alleles for a gene.
Identify the statement that describes an individual who is homozygous for a gene.
An individual inherits two of the same alleles for a gene.
Where in the cell does translation occur?
At the ribosome
In certain breeds of chickens, black feathers (CB ) are codominant with white feathers (CW ). What is the genotype of a chicken of this breed with black feathers?
CBCB
Move easily through the lipid bilayer of the plasma membrane
Carbon Dioxide
A good analogy for the genome and the epigenome is
Computer hardware and software
The promoter is found on?
DNA
Which of the following is NOT directly involved in translation?
DNA
Gene?
Determines a particular characteristic of an organism, codes for a specific protein or RNA, acts as the basic unit of heredity
Which of the following best describes you (as an adult)?
Diploid, multicellular adult
Gene regulation that takes place as the DNA is uncoiled and loosened from the nucleosome to allow the binding of transcription factors is best called
Epigenetic level
Both strands of a DNA double helix are transcribed. True or False
False
Each cell of your body has only the genes needed for the proteins needed by that cell. True or False
False
In a gel, small DNA fragments move toward the positive electrode and large fragments move toward the negative electrode.
False
The cap and tail are added to the spliced RNA in the cytoplasm of the cell.True or False
False
There are alternative ways to splice the introns during RNA processing in the nucleus. True or False
False
How did researchers treat pregnant mice to make sure the offspring would be brown and thin (as opposed to yellow and obese)?
Fed them food with methyl groups
Red-green color blindness is a recessive, X-linked trait. Which statements describe the differences between how the trait for color blindness is expressed in males and females?
Females with one recessive allele and one dominant allele will not express the trait and Males are more likely to express the trait than females.
You inherit your ______________________ but you can alter your __________________________."
Genome...epigenome
What happens during anaphase I of meiosis?
Homologous chromosomes separate but sister chromatids remain joined at their centromeres.
Lily, a student in an introductory biology class, learns that some alleles, such as blood type alleles IA and IB, are codominant with one another. She also learns that blood type allele i is recessive to the IA and IB alleles. Lily knows that her mother has blood type AB and her father has blood type A, but she does not know her own blood type. Identify all the possible genotypes for blood type that Lily may have.
IAi, IBi, IAIB, IAIA
Chromosome?
It is a contiguous piece of DNA, is a unit of DNA carrying genetic information encoded in genes, functions to package, organize, regulate access to DNA, is the largest molecule in cell, is a linear or circular molecule
Identify why this codon functions as a stop codon.
It is formed by a mutation and has no corresponding mRNA anticodon.
How are DNA fragments separated using gel electrophoresis?
Larger DNA fragments move more slowly through the gel than do smaller fragments.
In which organism did the researchers study the agouti gene?
Mouse
contains DNA in the cell
Nucleus
Gene regulation that takes place when the RNA is processed and exported to the cytoplasm is best called
Post-transcriptional level
Gene regulation that takes place after the RNA is translated into the polypeptide chain in the cytoplasm is best called
Post-translational level
During transcription what enzyme adds new nucleotides?
RNA polymerase
Which enzyme is responsible for linking nucleotides together to make mRNA?
RNA polymerase
protein complex that makes RNA polymers corresponding to a DNA template
RNA polymerase
What happens during the elongation step of DNA transcription?
RNA polymerase moves along the template strand of the DNA creating an mRNA strand.
What is a likely evolutionary advantage of sexual reproduction over asexual reproduction?
Sexual reproduction results in greater variation in the offspring
What happens during anaphase II of meiosis?
Sister chromatids separate from each other and migrate to opposite ends of the cell.
How could one identical twin have cancer and the other doesn't?
Some genes are turned off in one of the twins.
Which of the following are properties of protein-facilitated active transport?
Substances move from an area of lower concentration to an area of higher concentration and Substances cross the plasma membrane by being pumped through a protein using ATP.
The process of meiosis is responsible for creating much of the genetic variation seen in sexually reproducing organisms. Which events in the process of meiosis generate this genetic variability?
The arms of adjacent chromatids cross over and switch places with each other in prophase I and A homologous pair lines up along the metaphase plate independently of the other pairs.
What happens during the termination step of DNA transcription?
The mRNA detaches from the RNA polymerase as the RNA polymerase leaves the DNA strand.
Which choice describes diffusion?
The movement of a substance from a region where it is more concentrated to a region where it is less concentrated down its concentration gradient.
What occurs during the heating cycle of PCR?
The two strands of DNA are separated
Which statement describes the central dogma of biology?
Transcription is the process of synthesizing RNA from DNA. Translation is the process of synthesizing an amino acid sequence from RNA.
Gene regulation that takes place as the RNA is transcribed in the nucleus is best called
Transcriptional level
All cells in a person have the same genes.
True
All the skin cells on your finger have the genetic information needed to make the proteins produced by liver cells. True or False
True
Biotechnology applications include medicine, agriculture, industrial and household applications. True or False?
True
Identical twins have the same nucleotide sequence in their DNA. True or False
True
Prior to both mitosis and meiosis, chromosomes are duplicated. True or False
True
RNA is single-stranded while DNA is double-stranded- True or False
True
Which RNA nucleotide will pair with an adenine on the DNA molecule?
Uracil
Which of the following is unique to RNA?
Urcail
How do we study epigenetics in humans?
Use identical twins
What is a peptide bond?
a covalent bond formed when the carboxyl group of one molecule reacts with an amino group of a different molecule
Which statement describes a gene?
a section of DNA in which the code for a protein is located
Which of the following is the definition of a sex-linked trait?
a trait that is coded by a gene located on a sex chromosome
Which of the following requires energy (ATP) to be expended?
active transport
Which of the following will be used to move material into a cell against the concentration gradient?
active transport
The F1 generation of a cross TT x tt will be
all Tt
What are the monomers, or building blocks, of a protein?
amino acids
Translation?
amino acids added to peptide chain, requires tRNA, happens in ribosome, builds protein
Which of the following defines an individual that is true-breeding for a particular trait?
an individual that is homozygous for the gene that encodes the trait
Which statement describes dominant alleles?
any allele that can hide the presence of a different allele
What happens during replication?
both DNA strands are duplicated, described as semi-conservative, DNA polymerase
A methyl group is composed of which two elements?
carbon and hydrogen
contains a carbohydrate chain that allows the body to recognize its own cells
cell recognition protein
Which of the following are common to all 20 amino acids?
central carbon, amino acids, R group, carboxyl group
contains a passage that spans the entire membrane and permits only specific molecules to diffuse across
channel protein
Another word for shriveled cell is ____________________.
crenated
Which of the following will most likely occur when red blood cells are placed in a hypertonic solution?
crenation - because there is a net movement of water out of the cells
Your body cells are ____________, which mean they have two of each "kind" of chromosome.
diploid
Each cell that enters meiosis is ________, which can be designated as ___.
diploid...2n
A salt concentration of .9% salt is isotonic to red blood cells. Which of the following solutions would be hypotonic to red blood cells?
distilled water
How many DNA molecules would you have after 3 cycles of PCR?
eight
participates in chemical reactions involved with metabolism
enzymatic protein
Which portions of the transcribed RNA will become the mRNA that undergoes translation in the cytoplasm?
exons only
A Glucose molecule would move across a plasma membrane by which process?
facilitated diffusion
An individual has the genotype XX and has 45 autosomes, including 3 copies of chromosome 21. This person will be ________ and the condition is known as ___________.
female...Down syndrome
An individual has the genotype XO. This person will be ________ and the condition is known as ___________.
female...Turner syndrome
Tertiary
form three-dimensional shape
Once a length of DNA is cut into pieces, the pieces can be separated using
gel electrophoresis
A methyl group attaches to _________________ and turns them_________________.
genes, off
What type of protein is present in red blood cells to transport oxygen?
hemoglobin
Consider pea plants with purple/white flower color. Purple color is dominant to white flower color. A pea plant with purple flowers but unknown genotype is crossed with a pea plant with white flowers. The offspring show 14 plant with white flowers and 10 plants with purple flowers. What is the genotype of the parent pea plant with purple flowers?
heterozygous
Chromosome #7 from your dad and chromosome #7 from your mom are _______________________ chromosomes.
homologous
Meiosis 1
homologous chromosomes fail to separate, result in 4 abnormal cells
A recessive trait is observed in individuals that are __________ for that trait.
homozygous only
Biological membranes are present in all cells, and they make up the endomembrane system of eukaryotic cells. They have many functions, including acting as barriers that selectively allow the transport of small molecules and ions into and out of the cell or organelle. A biological membrane is a bilayer that contains lipids with
hydrophilic head groups oriented toward the solvent (extracellular fluid and cytosol) and hydrophobic tail groups pointing inward.
The head of a phospholipid bilayer is what?
hydrophilic, phosphate rich
How are biological membranes held together?
hydrophobic interactions
A solution with a higher solute concentration is ______________________ to a solution with a lower solute concentration.
hypertonic
Water intoxication (or excess consumption of water) can lead to swelling of the brain (or cerebral edema). For the brain to swell, what type of solution is the brain placed into?
hypotonic
Consider the dialysis tubing used in lab. The dialysis tubing is ____________ to chloride ions and __________ to water.
impermeable...permeable
Where in the cell does transcription occur?
in the nucleus
An anticodon is a sequence of three nucleotides that
is found on transfer RNA and is complementary to messenger RNA codons.
connects cells together and facilitates communication between them
junction protein
DNA fragments will move slower in a gel if the fragments are
large
Which of the following are components of biological membranes? Select all that apply.
lipids and proteins
An individual has the genotype XXY. This person will be ________ and the condition is known as ___________.
male...Klinefelter syndrome
Genome?
may include plasmids, describes the collection of all of the replicable genetic material of a cell or organism, each organism has one, encodes all the heritable traits of an organism
The phosphate groups of nucleotides have a net _______ charge.
negative
The tail of a phospholipid bilayer is what?
non-polar, does not mix with water, fatty acid chains
Many errors can occur during meiosis. Which term describes the process of sister chromatids not separating at the centromere during cell division?
nondisjunction
Which statement describes an allele?
one variation of the code for a protein
Which of the following is required to include in your PCR tube?
orginial DNA, free nucleotides, Taq polymerase, primers
Which of the following would move across a plasma membrane via simple diffusion?
oxygen gas
An individual who is heterozygous for a trait has a
pair of nonidentical alleles
The order and sequence of amino acids is the ______________ structure of protein.
primary
region of DNA that recruits the transcriptional machinery
promoter
A restriction enzyme is a type of
protein
Quaternary
protein subunits forming a complex structure
Epigenetic therapy in treating MDS leukemia, a cancer of the blood and bone marrow, include which of the following?
reactivating genes
recognizes and binds to signal molecules, leading to a reaction within the cell
receptor protein
Select the phrases that describe the plasma membrane.
regulates transport of molecules into and out of the cell, creates a barrier between the inside and outside of the cell
site of protein synthesis
ribosome
Primary Structure
shapeless strand of amino acids
Transcription?
single DNA strand is used to produce mRNA, happens in nucleus
Meiosis 2
sister chromatids do not separate at the centromere, result in 2 abnormal cells
Need help from a protein to cross the membrane because they are repelled by the lipid bilayer
sodium chloride, calcium ions, amino acids, glucose
Based on information in your lab exercise, Activity 4, what type of mutation is responsible for MSUD?
substitution
provides amino acids to growing protein chain
tRNA
Suppose Jennifer has a PCR product that contains three DNA fragments of 500, 800, and 900 base pairs in length. She separates the three fragments using gel electrophoresis. Which fragment will migrate the farthest from the wells at the top of the gel?
the 500 bp fragment
Genotype
the allele combinations an organism has, Rr
Crossing-over is
the exchange of non-sister chromatid segments.
A test cross is used to determine
the genotype of an individual
Plasma membranes are selectively permeable (semipermeable), meaning that
the membrane permits the transport of only certain substances.
Which statement describes a genotype?
the pair of DNA sequences an organism has for a trait
Phenotype
the physical expression of a gene, baldness
Which statement describes a phenotype?
the physical trait produced by an organism's genetic makeup
Gel electrophoresis is used to separate DNA on the basis of size and charge. DNA will move toward ___________electrode.
the positive
Select the description of RNA splicing.
the process by which noncoding regions are cut out of pre-mRNA and coding regions are joined together to form mature mRNA
may use energy to move substances across a membrane
transport protein
Which of the following type of activity is defective in a person with cystic fibrosis?
transporting ions across a membrane
In the obese and yellow mice, the agouti gene is
turned on all the time
Secondary Structure
twisted into alpha helices and pleated sheets, only formed by some proteins
Allele
variation of a gene, R or r
Osmosis is the diffusion of _____________.
water