Previous Test questions Flashcards
1
Q
What biological molecule do viroids and retroviruses use store and transmit genetic information?
A
RNA
2
Q
DNA contains the purines _________, while RNA contains the pyrimidines _________.
A
Adenine and guanine / cytosine and uracil
3
Q
_______________ are the nitrogenous bases found in DNA, whereas ________________ are the nitrogenous bases found in RNA.
A
adenine, cytosine, guanine, thymine / adenine, cytosine, guanine, uracil
4
Q
You recently isolated a double-stranded DNA molecule with 1000 purines and 1000 pyrimidines. This molecule could consist of precisely -
A
1000 guanine and 1000 cytosine nucleotides
5
Q
What property of the DNA molecule allows cells to recognize DNA damage and repair this damage?
A
The ability of complementary base pairs to interact by forming hydrogen bonds
6
Q
Which bases form the hydrogen bonds that enable the two strands of the double helix to bind to one another so effectively
A
Adenine forms 2 bonds with thymine, and guanine forms 3 bonds with cytosine
7
Q
What is a false statement about lipids?
c) Some of our hormones are triacylglycerols (triglycerides)
A
Some of our hormones are triacylglycerols (triglycerides)
8
Q
In all single-cell species and multi-cell species, which molecule stores the exact sequence of amino acids in every protein and the exact sequence of nucleotides in every specialized RNA molecule?
A
DNA
9
Q
What is the unique function of polynucleotides?
A
The storage and transmission of genetic information
10
Q
What is not an example of an essential function of RNA?
A
The storage of excess food energy
11
Q
What type of biological molecule generally must fold into a specific, complex 3-Dimensional structure after it is made in order to become biologically-active?
A
Protein
12
Q
Fever is induced in response to the detection of some pathogens (disease-causing agents). How could the fever response possibly deactivate some of the disease-causing proteins that pathogens produce?
A
They could be denatured
13
Q
What is a direct result of improper protein folding?
A
Mad Cow Disease
14
Q
Where is DNA localized within most human cell types?
A
Nuclei and mitochondria
15
Q
Specific protein/DNA interactions are essential for life to occur. The surface of a protein that binds directly to DNA might exhibit which characteristic?
A
Positive electrical charge
16
Q
We discussed the relationship between the size of a carbohydrate and its function. Which carbohydrate would not be a good candidate to be distributed to all of the cells in the body of a large organism?
A
Glycogen
17
Q
Which carbohydrate stored in our muscle cells and liver cells would decline in concentration after we participated in three hours of demanding physical activity?
A
Glycogen
18
Q
We discussed the relationship between the size of a carbohydrate and its function. Which statement regarding monosaccharides is true?
A
They can be imported into cells and exported from cells
19
Q
We discussed the relationship between the size of a carbohydrate and its function. What is a true statement regarding polysaccharides?
A
Chitin is used to provide structural support in many animal species
20
Q
A mutant plant recently was identified that is extremely short due to a lack structural support. Which carbohydrate probably is affected in this mutant plant?
A
Cellulose
21
Q
Why do so many cultures include specific types of plant foods with every meal?
A
This practice provides a complete set of essential amino acids
22
Q
Which biological molecule, when it is improperly folded, has been linked to some neurodegenerative disorders?
A
Protein
23
Q
What generally is not a primary function of proteins?
A
Waterproofing surfaces
24
Q
Why does the structure of a protein largely determine its function?
A
Structure determines the ability to interact with other molecules
25
Which group of monomers do our cells use to form polypeptides?
Amino Acids
26
How does the hydrophobic effect relate to the assembly of some biological structures?
It allows some types of molecules to form the lipid bilayer
27
Which specific type of biological molecules interact with one another, in the presence of water, to form a lipid bilayer?
Phospholipids
28
What is a true statement regarding lipids?
Lipids generally have a uniform electrical charge distribution that prevents them from interacting with hydrophilic water molecules
29
Which specific biological molecule is specialized to store excess food energy effectively?
Triglyceride
30
A malnourished child that lacks the substrates (molecular building blocks) to synthesize some lipids could have a diet insufficient in -
Essential fatty acids
31
Which characteristic makes ribozymes such potentially attractive pharmaceuticals?
Degrading RNA with a specific nucleotide sequence
32
We discussed how malnutrition can result from the lack of one or more essential nutrients. Which disorder results from the absence of the essential amino acid tryptophan?
Pellagra
33
We discussed the relationship between the size of a carbohydrate and its function. Which carbohydrate would we expect to find in the human bloodstream?
Glucose
34
Lipids play many roles in animals and plants. Which function is not performed by lipids in plants?
Catalysis
35
Which combination of lipids would be expected to occur in cellular membranes?
Phospholipids, steroids
36
The possibility that surgical equipment could be contaminated with prions is a valid concern among health care professionals. Which treatment would have the highest probability of reducing the activity of prions contaminating the surface of a scalpel?
Treat the surface with an enzyme that degrades proteins
37
Which type of stem cell is totipotent?
Embryonic (before or at the 8-cell embryo stage)
38
Among the types of stem cells we discussed, which type should be used to study how a single cell develops into an organism?
Embryonic (before or at the 8-cell stage)
39
What is a true statement regarding stem cell niches in the human body?
They probably help to maintain adult stem cells in an unspecialized state and respond effectively to Go-Signals
40
We discussed the types of tissues that interact to form animals and those that interact to form plants. Which type of tissue in animals and which type of tissue in plants cover all surfaces exposed to the environment?
Epithelial and Dermal
41
We discussed the internal structures that exist within prokaryotic and eukaryotic cells. What is one difference between the internal structures within prokaryotic and eukaryotic cells?
Micro-compartments in prokaryotes are surrounded by a protein shell, whereas the organelles in eukaryotes are surrounded by a membrane
42
Prions, viroids, and viruses are pathogens (disease-causing agents) that typically are smaller than prokaryotic cells and eukaryotic cells. Why aren't these pathogens considered the most fundamental units of life?
They cannot obtain and use energy, repair, or reproduce independently
43
Which specialized, internal structures within eukaryotic cells are specialized to perform specific biochemical functions?
Organelles
44
The human body regulates the cell cycle with great precision. Why must our bodies regulate the cell cycle with such precision?
- The activity of all 220 cell types must be coordinated to serve the body’s overall needs
- The loss of cell cycle control could result in cancer
- Our adult stem cells must only divide when it serves the overall needs of the body
- A loss of cell cycle control could prevent the proper repair of injured cells and tissues
45
The human body regulates the cell cycle with great precision. Which mechanism evaluates critical biochemical events at specific points in the cell cycle?
Checkpoints
46
How will a newly formed cell in the G1 phase respond when it does not recognize a Go-Signal?
This cell will exit the cell cycle and enter the G0 phase
47
In an adult stem cell, the activation of the G2 checkpoint resulted in the correction of a critical biochemical error. What is the next step for this adult stem cell after correcting this error?
Enter the M Phase
48
The human body instructs a specific population of adult stem cells to divide when a new supply of cells is required. How do our bodies accomplish this?
Go-Signals and their receptors
49
Which family of proteins bind to and stimulate the activity of the cyclin-dependent kinases that regulate the transition from one cell cycle phase to the next (G1 to S Phase, for example)?
Cyclins
50
In order for the human body to grow, develop, repair, and reproduce its trillions of cells must be able to communicate effectively with one another. All of the following are directly involved in cell signaling (cell to cell communication) except for -
DNA Polymerase
51
The hydrophobic, steroid hormones estrogen and testosterone are Go-Signals for some cell types in the human body. How are these hydrophobic hormones recognized by the proper target cells in the body?
Receptors within the cell
52
In order to maintain proper cell cycle regulation, the cyclin proteins must be degraded after activating the proper cyclin-dependent kinase. How do our cells degrade the cyclin proteins, and other proteins, in a regulated manner?
Proteasome
53
An adult stem cell no longer requires a "Go-Signal" to divide. What is one possible cause?
A Tyrosine Kinase Receptor is constantly activated
54
A population of adult stem cells in a specific stem cell niche responds to a specific "Go Signal". This "Go-Signal" is a large, hydrophilic protein. Where would the receptor for this "Go-Signal" be localized?
Cell membrane
55
What is the name of a nucleotide sequence that contains the information to make a specific polypeptide or specialized RNA molecule?
Gene
56
Which event enables our adult stem cells to pass through the G1 (Gap 1) restriction point checkpoint?
Go-Signal recognition
57
Which part of an eukaryotic gene determines the amino acid sequence of the polypeptide the gene encodes?
Exon
58
A cell has a lethal defect that prevents it from making the short, complementary RNA primer molecule that is required for DNA replication to occur. Which component of DNA replication must be defective?
Primase
59
Which enzyme preserves the integrity of the information stored in the genes located at the ends of our DNA molecules/chromosomes?
Telomerase
60
Which nucleotide sequence is not part of an eukaryotic gene?
Origin of replication
61
Mitotic Cell Division is necessary for which essential processes to occur in multi-cell species?
- Defense against foreign invaders (pathogens and parasites)
- Growth
- Renewal of older tissues
- Replacement of damaged cells and tissues
62
We discussed the phases of mitosis and how they relate to the proper delivery of a complete set of chromosomes to each daughter cell. During which phase of mitosis does the nuclear envelope (membrane) disassemble so the chromosomes can begin to interact with the microtubules of the spindle?
Prometaphase
63
Which statement accurately relates to the competitive inhibition of enzyme activity?
Inhibitors bind to the active site
64
Enzymes are absolutely essential for life to occur. Which statement regarding enzymes is true?
Enzymes reduce activation energy
65
Which types of biological molecules form the enzymes that enable cells to coordinate and execute all of their required chemical reactions with such remarkable precision?
Proteins & RNA
66
We discussed the remarkable properties of enzymes. What is a true statement regarding enzymes?
A specific enzyme increases the rate of a specific chemical reaction
67
The activity of a specific enzyme is directly regulated by the concentration of the product molecule it generates. This is an example of -
Negative Feedback
68
We discussed some of the mechanisms that cells use to reversibly and rapidly regulate enzyme activity. Non-competitive inhibition is an example of which type of regulation?
Allosteric Regulation
69
A child's diet lacks some minerals (iron, calcium, magnesium). How could this mineral deficiency cause malnutrition?
These minerals could be cofactors
70
The lack of which vitamin(s) in the diet would prevent some of the enzymes that modify carbohydrates from functioning?
B Vitamins
71
What are some of the health concerns currently associated with stem cell-based therapies?
- Adult stem cells injected into a patient could divide in an uncontrolled manner
- Adult stem cells injected into a patient could result in cancer
- Adult stem cells injected into a patient could result in an undesirable immune system response
- Induced pluripotent stem cells (IPS) injected into a patient could result in an undesirable immune system response or cancer
72
We discussed the contributions that mitosis and cytokinesis make to mitotic cell division. Consider a cell that completes mitosis but cannot complete cytokinesis. How would the failure of cytokinesis affect the total number of chromosomes in the nucleus?
There would be twice the number of chromosomes compared to a cell that completed cytokinesis
73
Which process enables the production of haploid (1N) gametes from diploid (2N) cells in sexually-reproducing individuals?
Meiotic cell division (meiosis)
74
Which statement regarding meiotic cell division (meiosis) is true?
Meiosis occurs in our ovaries and testes
75
We discussed how some genetic disorders (Down, Klinefelter, and Turner Syndrome) can result from errors made during meiotic cell division. Which specific process can result in aneuploid gametes?
Non-disjunction
76
We discussed the relevant events that occur during meiosis 1 and meiosis 2. Which essential event occurs during meiosis 2?
Sister chromatid separation
77
Each autosome (chromosomes 1-22) in the sperm or egg you produce can contain alleles from both your mother's and father's homologous chromosomes. Which process makes this possible?
Crossing over
78
Your mother has 46 total chromosomes. Your father has 46 total chromosomes. Why don't the nuclei of your cells contain 92 chromosomes?
Meiotic cell division
79
What result of meiotic cell division increases the probability that sexually-reproducing populations can adapt to changing environmental conditions?
Increased genetic variation in populations
80
The goal of your research team is to develop a new drug that prevents the cancer cells in a tumor from receiving sufficient quantities of glucose and oxygen. This new anti-cancer drug should inhibit which specific process?
Angiogenesis
81
We discussed the differences between benign tumors and malignant tumors. Which characteristic of benign tumors makes them easier to treat than malignant tumors?
Cells in the benign tumor cannot metastasize
82
Which cancer treatment is intended to train the immune system to recognize and destroy cancer cells?
Vaccination
83
Which mutation would have the highest probability of allowing a cancer cell to metastasize?
A mutation that reduces the ability of cancer cells to bind to one another
84
We discussed the role that translation plays in gene expression. Where does translation typically occur in our cells?
Blood
| Cytoplasm/cytosol
85
Which membrane transport proteins are specialized to transport small, hydrophilic elements such as K+, Na+, Ca++, or Cl- from higher to lower concentration?
channel proteins
86
Some of our white blood cells have the ability to uptake a foreign invader and destroy it. A mutant white blood cell cannot uptake a virus it detected. This mutant white blood cell probably cannot perform which process?
Phagocytosis
87
Some cancer cells have the ability to release a growth factor (large, hydrophilic protein) that stimulates angiogenesis. Which mechanism exports multiple copies of this growth factor to the extra-cellular space (outside of the cell)?
Exocytosis
88
Our cells use different mechanisms to transport different types of substances (size, chemical properties) across the cell membrane. Our cells would require an active transport protein to perform which function?
Transport a hydrophilic substance from lower to higher concentration
89
Which organelles contribute to the synthesis of cellular membranes?
Golgi Apparatus and Endoplasmic Reticulum
90
We discussed the different types of endocytosis that our cells use to import some substances. What is one example of how our cells use pinocytosis?
Import food molecules dissolved in extra-cellular fluid
91
The cell (plasma) membrane is an extremely dynamic structure. What are some functions of the cell membrane?
- It forms the boundary between the cell and its surrounding environment
- It contributes to the regulation of the import of substances
- It contributes to the regulation of the export of substances
- It allows cells to recognize many types of signals (sensory capacity)
92
We discussed mutations, mutagens, and carcinogens. What is an accurate definition of a mutation?
A change in the nucleotide sequence of a DNA molecule
93
We discussed the two categories of genes that can increase the risk of a cell becoming cancerous (the transformation process). Which gene would not be considered a proto-oncogene?
Gene C encodes an enzyme that repairs DNA
94
We discussed how mutations in proto-oncogenes and tumor suppressor genes can eliminate proper cell cycle regulation. Which statement is true?
- One copy of an oncogene increases the risk of cancer
- Two copies of a wild-type (normal) tumor suppressor gene reduce the risk of cancer
- Two copies of an oncogene increase the risk of cancer
- Two copies of a wild-type (normal) proto-oncogene reduce the risk of cancer
95
Which gene probably is a proto-oncogene?
Gene A encodes a cyclin-dependent kinase (CDK)
96
We discussed the two categories of genes that encode proteins that regulate the cell cycle. Which category of genes encodes proteins that stimulate cell division in a highly regulated manner?
Proto-oncogenes
97
What are the categories of mutagens we discussed?
Biological
Chemical
Physical
98
We discussed the types of genes that regulate the cell cycle. Which category of genes encodes proteins that inhibit cell division in a highly regulated manner?
Tumor Suppressor
99
We discussed how transcription contributes to the ability of our cells to use the information stored in a gene to make a specific polypeptide. Which enzyme copies the information stored in a gene during transcription to make a messenger RNA molecule (transcript)?
RNA Polymerase
100
We discussed how messenger RNA (mRNA) is processed (chemically modified) after transcription. How is mRNA processed?
5' G-Cap is added
3' Poly-A Tail is added
Alternative splicing
Splicing
101
We discussed the nucleotide sequences, proteins, and enzymes that enable the transcription of a gene to occur. The elimination of which nucleotide sequence would prevent RNA Polymerase from binding to and transcribing a specific gene?
Promoter
102
We discussed the nucleotide sequences, proteins, and enzymes that interact to enable transcription to occur. Which group of proteins ensures that RNA Polymerase interacts with the proper nucleotide sequence so transcription can occur?
General transcription factors
103
We discussed the various types of processing (chemical modification) that are necessary to produce a mature, functional messenger RNA (mRNA) after transcription. Which of the following removes introns from a newly formed mRNA molecule and joins the remaining exons together to form a mature mRNA molecule?
Spliceosome
104
We discussed how translation contributes to gene expression. Which family of enzymes attaches the correct amino acid to the correct transfer RNA (tRNA) to ensure that translation is an accurate process?
Aminoacyl tRNA Synthetases
105
We discussed the medical (health) consequences of abnormal splicing. How can abnormal splicing increase the risk of cancer?
A protein is produced that is not destroyed by the proteasome
106
We discussed the extensive processing (chemical modifications) that messenger RNA (mRNA) experiences after transcription. Which type of processing allows a single gene to produce different versions of a polypeptide that are specialized for specific cell types?
Alternative Splicing
107
A new antibiotic was recently discovered that inhibits the translation process in disease-causing (pathogenic) bacteria. This antibiotic probably inhibits -
Ribosome
108
We discussed the various processes that are necessary for gene expression to occur. Which of the following converts the codon information in a messenger RNA (mRNA) molecule, also called a transcript, into a polypeptide?
Ribosome
109
A source of energy is required to synthesize the biological molecules produced during transcription and translation. Which source of energy specifically drives the translation process?
GTP
110
We discussed how some genes encode specialized RNA molecules. Which specialized type of RNA quickly and efficiently delivers amino acids to the translation machinery so they can be joined together during the translation process?
Transfer RNA (tRNA)
111
Many of the genes in the human population have different versions. What term is used to describe the different versions of a single gene that often exist in the human population
Allele
112
Which theory describes how the information stored in a gene is copied into a RNA molecule during transcription and how the information in this RNA molecule is used to make a polypeptide (protein) during translation?
Central Dogma
113
A specific model system is intentionally chosen to facilitate the study a specific biological process. Why did Mendel decide to use pea as a model system to study the mechanisms that regulate inheritance?
- Peas were relatively inexpensive to grow
- Peas were relatively inexpensive to grow in large numbers to achieve sufficient replication
- Matings/crossing between parental pea plants with different traits were controlled easily
- Pea seeds were inexpensive to buy
114
We discussed the biochemical basis of dominant and recessive disorders. Why do recessive disorders only develop when an individual inherits two copies of a loss of function allele?
No functional enzyme or protein is produced
115
A crop breeder must determine the genotype of a tomato plant that expresses a dominant phenotype that increases fruit yield. Which type of cross should she use to determine if the genotype of this tomato plant is homozygous dominant or heterozygous?
Test cross
116
We discussed the organelles in eukaryotic cells that contain DNA. Cytoplasmic inheritance in humans is due to the inheritance of which organelle?
Mitochondrion
117
Some of Mendel’s rules have been extended to account for some aspects of inheritance that were difficult to investigate using monohybrid or dihybrid crossing experiments in pea. What is one example of a more recent discovery?
One trait can be regulated by many genes (polygenic inheritance)
118
We discussed the terminology of Mendelian Genetics. What is a true statement?
Ploidy is the number of chromosome sets in the nucleus
119
We discussed how a point mutation can influence the expression of a gene. Which mutation probably would not influence gene expression?
A mutation that changes one amino acid in the protein the gene encodes
120
We discussed the medical consequences of point mutations. What is an example of a genetic disorder caused by a point mutation?
Sickle Cell
Hemophilia
Tay Sachs
Cystic Fibrosis
121
We discussed how to analyze human pedigrees effectively. Which pattern probably would be observed in a pedigree where a trait is transmitted in an X-linked recessive manner?
This trait is more common in males
122
We discussed how to analyze human pedigrees effectively. When analyzing a pedigree, which observation would suggest that a trait is transmitted in an autosomal recessive manner?
The parents share a common ancestor
123
Which specific term is used to describe an allele that influences two or more aspects of an individual's phenotype?
Pleiotropic
124
Achondroplasia is a form of dwarfism that occurs in heterozygotes. How could two wild-type parents, each with a homozygous recessive genotype (aa), have a child with Achondroplasia (Aa)?
A mutation could occur during gamete formation in one of the parents
125
We discussed how to analyze human pedigrees effectively. A pedigree shows that a father affected by a specific disorder has ten children who are all healthy (unaffected). This disorder trait probably is transmitted in which manner?
Cytoplasmic inheritance
126
We discussed how to analyze human pedigrees effectively. Every affected child in a pedigree has one affected male parent or one affected female parent. Which type of transmission does this observation indicate?
Autosomal dominant
127
Cystic fibrosis is an autosomal recessive disorder associated with thick, sticky mucous. What is one health consequence of this abnormal mucous?
Decreased ability of the digestive tract to absorb nutrients from food
128
We discussed some of the genetic disorders that are caused by a point mutation. Which autosomal recessive genetic disorder can be prevented by making dietary/nutritional modifications at the time of birth?
Phenylketonuria (PKU)
129
We discussed some of the genetic disorders associated with the sex chromosomes and autosomes (non-sex chromosomes). Why is the frequency of hemophilia higher in males compared to females?
Males are hemizygous for the X-chromosome
130
We discussed the biochemical basis of recessive genetic disorders and dominant genetic disorders. How can one copy of a mutated allele cause a dominant disorder phenotype such as Huntington's Disease?
A "rogue" protein is produced that interferes with normal cellular function
131
We discussed the range of mutations that can occur in the genome. What is a false statement?
A point mutation is an example of a chromosome abnormality
132
We discussed the types of point mutations that can occur in the genome. The insertion or deletion of a single nucleotide pair in a gene would result in which type of point mutation?
Frameshift
133
We discussed some of the genetic disorders in the human population. Which autosomal recessive genetic disorder increases the risk of skin cancer?
Albinism
134
We discussed how dominance, co-dominance, or incomplete dominance can be observed in the phenotype of heterozygous individuals. When the two different alleles are both expressed in the phenotype of a heterozygote, this is known as -
Co-Dominance
135
We discussed how dominance, co-dominance, or incomplete dominance can be observed in the phenotype of heterozygous individuals. When the heterozygote shows a phenotype that is intermediate between both parents, this is an example of -
Incomplete dominance
136
What type of experiment did Mendel design to determine if the alleles of two different genes move as a linked pair into gametes during meiosis?
Dihybrid Cross
137
We discussed the range of mutations that can occur in the genome. Which mutation is not an example of a chromosomal abnormality?
Nonsense
138
We discussed some of the genetic disorders in the human population. Which autosomal recessive genetic disorder is due to the inability of the lysosome organelle to degrade a specific lipid?
Tay Sachs
139
We discussed the biochemical basis of dominant genetic disorders and recessive genetic disorders. The "Haplo-Insufficiency Hypothesis" relates to which type of genetic disorders?
Dominant
140
We discussed the definition of an allele. Why does the information stored in the alleles of a single gene differ?
Different nucleotide sequences
141
We discussed the concept of phenotype. When do environmental conditions begin to influence the human phenotype?
Before Birth
142
Two fields were planted with genetically-identical seeds. The plants in one field are substantially taller than the plants in the other field. Which hypothesis most likely accounts for this difference in height?
Phenotype was affected by different environmental conditions
143
What is a medically-relevant example of co-dominance in humans?
The ABO Gene that regulates the ABO Blood Group
144
We discussed the terminology or "language" of Mendelian Genetics. Which statement regarding phenotype is true?
It results from the complex interaction between genotype and environmental conditions
145
We discussed the range of mutations that can occur in the genome. While using a light microscope to examine the nucleus of a plant cell, you observed that the nucleus contained eight sets of chromosomes rather than the normal complement of two sets of chromosomes. This is an example of -
Polyploidy
146
We discussed the range of mutations that can occur in the genome. A mutation occurred where one block of genes from one chromosome was attached to a different chromosome. This is an example of a -
Translocation
147
Point mutations have been shown to cause some genetic disorders. For example, sickle cell anemia is due to a point mutation that results in the beta-globin gene coding for a globin polypeptide that has one different amino acid compared to the wild-type (normal version) polypeptide. The sickle cell mutation is an example of a -
Missense Mutation
148
A point mutation occurred in a gene that codes for a polypeptide (protein). This mutation resulted in the production of a polypeptide that consists of substantially fewer amino acids. This is an example of a -
Nonsense Mutation
149
We discussed the range of mutations that can occur in the genome. A point mutation occurred in a gene that codes for a polypeptide (protein). This mutation does not change the amino acid sequence of the polypeptide encoded by this gene. This is an example of a -
Silent (Synonymous) Mutation
