Biology Practice Questions
The vegetation in Canada is similar to the vegetation that one finds in Siberia. This is mostly due to
equivalent rainfall and temperature.
The open ocean and tropical rain forests contribute the most to Earth's net primary production because
the ocean covers a huge surface area, and the tropical rain forest has a high rate of production
What is the earliest stage of life predicted by the experimental results of Dr. Ruth Blake?
Blue Stage 3.8 BYA.
The divergence of Pan and Homo occurred about 5-6 MYA. The last common ancestor was
The last common ancestor has not been found.
The following phylogenetic tree indicates that
The three domains of life arose from a primitive ancestor not yet identified.
The following diagram shows the origin of the H1N1 influenza virus that re-emerged in 2009 leading to a pandemic. The mechanism responsible is shown below by the arrow to the right that leads from the Eurasian avian-like swine. What is this term?
antigenic shift
Ancient photosynthetic prokaryotes were very important in the history of life because they
produced the oxygen in the atmosphere.
The oldest evidence of cellular life on Earth is
stromatolites dated at ~3.5-BYA in which fossilized prokaryotic cells were found.
Scientists commonly choose white blood cells that are going through mitosis to prepare karyotypes. Why?
During mitosis, chromosomes are more condensed than during interphase.
Identify the one correct answer below about Ebola, the disease.
Ebola reached epidemic levels in West Africa because of its ability to sustain human-to-human transmission.
Ecosystems are complex dynamic systems. They are characterized by all of the following statements except one. Choose the incorrect statement.
Ecosystems tend to be stable on long temporal scales because of recycling and regeneration.
A researcher treats cells with an inhibitor that prevents DNA synthesis from starting. This treatment would trap the cells in which stage of the cell cycle?
G1
There is the need for differential gene expression in humans because of one of the following. Identify the incorrect answer.
Gene expression is very straight forward because the genes lie in tandem, and all are turned on at the same time. There is no need for differential gene expression. Cells differentiate by the action of enzymes. There is one master homeotic gene that turns on all genes at one time in all cells.
Which of the following statements about genetic diversity over a few generations is true?
Genetic diversity is enhanced by crossing over during prophase I of meiosis. Genetic diversity is enhanced by homologous chromosomes in meiosis that carry different versions of genes. Genetic diversity is enhanced by independent orientation of chromosomes at metaphase I during meiosis. Genetic diversity is enhanced by random fertilization.
A population bottleneck will likely result in which of the following?
Genetic drift
Which of the following is NOT a quality of binocular vision with forward looking eyes?
Large field of view
During mitosis, the chromosomes move because _______________________________.
they attach to a dynamic, precisely regulated mitotic spindle composed of microtubules.
Eutrophication is
Massive overgrowth of algae or photosynthetic bacteria in a water system due to the addition of nutrients and inorganics such as phosphorus and nitrogen.
Mass extinctions
Can be responsible for an adaptive radiation where new species develop to occupy newly opened niche environments.
What modern evidence is consistent with the hypothesis that mitochondria & chloroplasts arose through endosymbiosis.
DNA structure & cell division of mitochondria & chloroplasts are similar to those in bacteria. Mitochondria & chloroplasts transcribe and translate their own DNA. Their ribosomes are more similar to bacterial ones (70S) than eukaryotic ribosomes (80S). Eukaryotic cells cannot make more mitochondria or chloroplasts
Which of the following is a biological macromolecule that can both store heritable information and catalyze chemical reactions?
RNA
Technological advances to manipulate gene expression include which one of the following.
RNA interference gene silencing (RNAi).
In what way is SARS-CoV-2 different from the viruses that cause influenza and Ebola?
SARS-CoV-2 has one single stranded RNA genome, yet the viruses that cause influenza and Ebola have RNA genomes that have multiple individual RNA segments that encode specific proteins.
The advances in precision medicine correlate with advances in technology including all but one of the following. Identify the false statement.
Sanger method of DNA sequencing.
The following are common characteristics of eukaryotic cells except one INCORRECT statement below.
Some eukaryotic cells store their genetic information in RNA
Two populations of a species that inhabit the same geographical region but have become sexually isolated is an example of what form of speciation?.
Sympatric
If the DNA template strand sequence for mRNA synthesis is ACC AAA CCG, the mRNA sequence is
UGG UUU GGC
In the salt marsh of the North Carolina coast, the role of the blue crab was to
consume the periwinkle snails and protect the marsh grass
In eukaryotes, DNA packing seems to affect gene expression primarily by
controlling access to DNA.
Aquatic dead zones are
low oxygen zones
Removal and exclusion experiments indicate that
predators have a major impact on prey survival and abundance
During the Hadean Eon, ~4 BYA, what possible life form could emerge?
protocells
Gross Primary Production
total amount of energy fixed by all autotrophs (plants) per unit area and time
What compounds and conditions did Stanley Miller use to perform his 1953 experiment to simulate the atmosphere of early Earth to test the hypothesis of abiotic synthesis of organic molecules?
water vapor, H2 (hydrogen gas), CH4(methane), NH3 (ammonia), spark for lightening.
The Cambrian Period was characterized by unprecedented proliferation of species & phyla including an explosion of animal diversity. Identify the CORRECT statement(s) below.
Increased volcanic activity raised CO 2 levels which in turn increased the greenhouse effect leading to glacier melting and huge runoff of minerals, nutrients, and microorganisms into the oceans. Dramatic increase in atmospheric O 2 to support larger animals. Extremophiles were able to survive the extreme conditions of glaciation & volcanic activity. Snowball Earth or the complete glaciation of Earth.
The levels of organization in Ecology include the following: Identify the organization from the most specific to least specific.
Individual > Population > Community > Ecosystem > Biome > Biosphere
Based on ribosomal RNA nucleotide sequences, the major kingdoms of the biological world are as follows:
Bacteria, Archaea, and Eukarya
The structure of DNA is very stable because of the following.
Orientation of the strands is antiparallel. The two strands are held in register through precise hydrogen bonding between adenine & thymine and guanine & cytosine. Stability results because of a large number of noncovalent interactions including hydrogen bonds, hydrophobic interactions and van der Waals interactions. The absence of uracil.
Which of the following is NOT considered evidence that RNA preceded DNA in early cellular systems.
RNA is more stable than DNA.
Which of the following is TRUE regarding the lac operon in E. coli?
Regulation of the lac operon is very different from eukaryotic gene regulation. The lac operon messenger RNA carries information for synthesis of several proteins. The promoter is the binding site of RNA polymerase. The operator is the binding site for the lac repressor.
The following are statements about emergent complexity. Choose the correct answer(s).
Robert Hazen proposed that emergence and the origin of life is the "missing law". Robert Hazen proposed that life arose as a sequence of emergent events, each the consequence of interactions among carbon-based molecules. The universe may be organized such that life spontaneously emerges given the appropriate condition and with sufficient time. Emergence of order & self-organization occurs in both abiotic and biotic systems, and the properties of each are similar.
In the North Pacific Ocean, two groups of the same species of killer whales ( Orcinus orca) appear to be forming two different species based on what they eat. One group eats fish while the other eats mammals such as seals. Scientists can tell what they eat based on their teeth because whales that feed on fish have significantly different wear patterns. Which of the following best describes the type of speciation event that is occurring in the whales?
Sympatric speciation
The following are common characteristics of eukaryotic cells except one correct statement below.
All eukaryotic cells exhibit intracellular motility. All cells share ~500 cellular metabolic reactions with many interconnections. The cell structure can vary. Common traits include intracellular membranes, at least one nucleus, complex cytoplasm with organelles such as mitochondria and chloroplasts in plants.
Different strains of influenza A occur each year because of
Antigenic shift.
What is the importance of funding research to develop artificial cells?
Anything that is living is a molecular machine and if we can determine the engineering plan, the parts, the chemicals, then we will have a better understanding of how life evolved
James Allison was awarded the 2018 Nobel Prize in Physiology or Medicine for the following medical breakthroughs. Which statement below is true.
He proposed that activated T-cells also had a second receptor that was a control switch or immune checkpoint that turned off activated T-cells. He developed antibodies to the checkpoint receptor that bound and inactivated the switch so that the T cells would continue to attack the cancer cells. He showed that the activated T-cells multiply, but turn off rather than continue to attack cancerous cells. He identified a key protein receptor that allows the immune system's T cells to recognize the antigens of infected or abnormal cells including cancer cells.
The Sixth Extinction refers to
Present time.
What are the two main approaches to scientific inquiry that were presented in class?
Reductionist and Holistic
Why do the tropics and the windward side of mountains receive more rainfall than areas around latitudes 30º north and south and the leeward side of mountains
Rising warm, moist air cools and drops it as rain.
The following are common characteristics of eukaryotic cells except one incorrect statement below.
Some eukaryotic cells store their genetic information in RNA.
The habitat is the environment where an organism lives. There are both abiotic and biotic factors that affect the organisms that live there. Identify an important abiotic factor.
Temperature and water
The Oxitec Friendly Mosquito technology is based on the following:
a CRISPR gene drive technology that kills Aedes aegypti female mosquitoes only.
A carrier of a genetic disorder who does not show symptoms is most likely to be____________ to transmit it to offspring.
heterozygous for the trait and able
Evolution operates to produce changes in
populations
During which stage of meiosis does crossing over and formation of tetrads occur?
prophase I
The leading hypothesis about the first system of inheritance in the earliest life forms involves
self-replicating RNA molecules aided by ribozymes.
DNA metabarcoding
was used to determine how the three closely related species of antelope can coexist in Mozambique's Gorongosa National Park.
The Hershey-Chase experiments in 1952 were important because they showed that
DNA was the hereditary material.
With limited resources, conservation biologists need to prioritize their efforts. Of the following choices, which should receive the greatest attention for the goal of conserving biodiversity?
a declining keystone species in a community
In the HHMI video with E. O. Wilson, he made a key observation about the relationship between the number of species & area in which they live. This rule was extrapolated to fragmentation of the rain forest and Yellowstone to the Yukon region. The observations showed that a decrease in habitat area resulted in
a decrease in species biodiversity.
Which of the following organisms introduced oxygen into the Earth's atmosphere?
cyanobacteria
Cells with two of each kind of chromosome are described by the term
diploid
Identify the following image.
karyotype
What is CRISPR/Cas9?
A defense system that bacteria use to protect against invading viruses. Exciting technology that offers promise for curing human diseases, advancing agriculture, altering pests that carry disease. Clustered Regularly Interspaced Short Palindromic Repeats . A gene-editing tool.
All are true of a genome graph except which one of the following.
A reference genome based on a few individuals.
Rachel Carson was one of the first scientists to bring environmental issues to the attention of the general public. What problem did she write about in her 1962 book Silent Spring?
effects of widespread use of the pesticide DDT
BRCA1 and BRCA2 are genes that are
essential for repairing damaged DNA.
Coevolution
is the evolution of two populations of different species in response to selection pressures that individuals from the two populations place on each other.
The term, anthropogenic, is often used in discussions of climate change and environmental impacts. This is because anthropogenic means
it is due to human activities.
A mouse that has the genotype AANnPpzz will have the same phenotype as a mouse with the genotype: (Note that the uppercase alleles A, N, P, and Z are dominant).
AaNNPPzz
After a week, what specific organic compounds did Stanley Miller find?
amino acids
Freshwater wetlands were originally assumed to just be swamps and of little value. However, that perspective has changed in the last 25-30 years.
Wetland water can either come from a nearby body of water or an underground supply. Wetlands can recycle nutrients and wastes. Wetlands can decrease flooding. Wetlands are defined as an area of land covered or saturated with freshwater for an extended period of time.
As one moves from high latitudes toward more equatorial regions, biodiversity increases. Which of the following is NOT a characteristic of equatorial regions and would NOT support this observation?
lower speciation rates
A Whittaker Diagram separates biomes by
precipitation and temperature
The Lacey Act
prohibits the illegal interstate or global sale, possession, trafficking, purchasing, smuggling, and transport of plant or animal wildlife.
Autism is a complicated genetic disorder. Identify the true statements.
New predictive approaches have resulted through using systems biology to identify an increase in common metabolites in autism not seen in normal children. There are somatic mutations that only appear in a small fraction of the cells of the body. The genetic profile was identified through deep sequencing techniques. Autism is typically not recognized until kids are 2-3 years old.
The general hypotheses that account for the disappearance of the Neanderthals include all butone. Which of the following is favored as a hypothesis?
Overall decrease in Neanderthal population numbers resulted in decrease in genetic diversity. Humans became more numerous. Climate change caused the population to become fragmented. Climate change impacted their population numbers.
Of the following human traits, which evolved first?
bipedality
Under what circumstances can simple chance affect the frequency of genes in a population?
When the population is very small thus amplifying the effect of random chance.
Project Drawdown defined drawdown as
moment in time when global greenhouse gases will stop & reverse their current upward trajectory and begin to decline year after year.
Most genetic disorders of humans are caused by
recessive alleles.
The statements below are true for the role of microRNA gene expression with the exception of one incorrect answer. Identify the correct answer.
microRNAs are a natural protection against viral RNA. Dicer gene is essential for generation of microRNA in mammals. microRNAs block translation of mRNAs. microRNAs are small single-stranded RNA that bind complementary sequences of mRNA.
All are true of a genome graph
A network of DNA sequences typically from 1,000 or more individuals. More accurate because captures regions that were not identified previously because of insertions, duplications, and or deletions. May identify mutations missed by sequence comparison to a single genome. This universal genome approach could store information about from whom the genome(s) came.
The results of the Human Genome Project have changed how we view our DNA/genome. What were the major surprises? Identify the incorrect answer.
A single individual's DNA was sequenced; therefore little was initially learned from it.
What is the scientific evidence that allows us to reconstruct the origins of Earth and evolution of life?
Analysis of rocks, meteorites, volcanic rocks/sediment, stromatolites, uranium ore, sedimentary rocks. The Stanley Miller Experiments. The discovery of RNA and RNA enzymes, ribozymes. Technological advances in modern telescopes to observe and study the birth of a solar system and planets
Which of the following statements about genetic diversity over a few generations is false?
Genetic diversity is enhanced by mutations.
A community is built upon relationships. Identify the one incorrect answer below about community relationships.
In competitive relationships, as the acorn example of the squirrels & black bear, the black bear always wins as the apex species.
Over the last 25 years, there has been a significant increase in emerging infectious diseases world-wide that have had a significant impact on human health. The contributing factors include
lack of access to quality health care. increasing human contact between wild and domestic animals. demographic changes including population growth, inhabiting new areas, civil unrest, and wars. increased travel, commerce, and development of large urban areas.
While some species can exhibit exponential growth on a relatively short time frame/period after disruption of some type, it is more common for a population to exhibit logistic growth. Environmental factors that restrict population growth are
limiting factors
The 3-D structure of RNA is very different from DNA because of the following except
phosphodiester linkages between the nucleotides.
Recently, Lake George experienced a brief Harmful Algal Bloom (HAB). HABs are different from eutrophication because of which of the following:
presence of high concentration of cyanobacteria that release toxins.
Which of the following is true for BOTH protocells and cellular life?
They both have selectively permeable or impermeable membranes.
The fossil of Ardipithecus ramidus (Ardi) was found after Lucy but was a critical find because
Ardi walked upright but also had the characteristics of a climber. Ardi was dated to 4.4 MYA and revealed that she was a peculiar mosaic of traits. The surrounding fossils indicated that bipedality evolved in the woodlands and not grasslands. Ardi's skeleton is representative of the earliest known phase of human evolution.
The following statements are true about Zika except one. Identify the incorrect response.
Zika is no longer an emerging infectious disease of concern because most people carry antibodies to Zika resulting from the outbreak in 2016.
The fossil record shows that anatomically, modern Homo sapiens evolved at least 200,000 years ago and brain shape became comparable to ours today at least 100,000 years ago. Yet, the cave art, tools, and artefacts support the hypothesis that modern complex technology and culture evolved more slowly and became evident 50,000-60,000 years ago. Which of the following do represent behavioral modernity?
We developed the capability for complex technology. We sing and dance. We developed the capability to build boats and sail across large bodies of water.
Freshwater wetlands were originally assumed to just be swamps and of little value. However, that perspective has changed in the last 25-30 years. Choose the one incorrect statement about wetlands.
Wetlands are characterized by relatively low species diversity.
The results of the Human Genome Project have changed how we view our DNA/genome. What were the major surprises? Identify the correct answer.
There is repetitive DNA sequence between the genes. Gene control sequences (promoters, enhancers, microRNA) make up 24% of the human genome. Protein-encoding genes make up ~1.5% of our genome. 98.5% is noncoding DNA. There are millions of transposable elements that are repeated throughout the genome.
James Allison and Tasuku Honjo were awarded the 2018 Nobel Prize in Physiology or Medicine because of which one of the following?
They identified key proteins on T cells, called immune checkpoint proteins, that were normally responsible for turning off activated T cells.
Genetic changes that underlie oncogenesis alter fundamental properties of cells including all of the following
Cells acquire the ability to proliferate that does not require an external inducing signal. Metastasized cells can use the cell's cytoskeleton to promote tumor cell streaming. Cells can acquire the ability to metastasize. Allow cells to evade normal growth controls.
Rosemary and Peter Grant began studying the finches endemic to the Galapagos Islands in 1973 and have continued to the present. These field studies because they occurred annually have been very powerful in showing how geography and ecology can both drive the evolution of new species. The key concepts from the Grants findings include which of the following:
Habitat and ecological niches are constantly changing For two groups to become distinct species, traits must change in ways that will keep members of each group reproductively isolated such that they do not mate and produce fertile offspring. When two groups within one species become geographically isolated, genetic changes in one group will not be shared with members of the other, and vice versa. A single ancestral population of finches has given rise to 13 separate species, each adapted to different habitats. Evolutionary change can occur rapidly, in only a few generations. However, major change such as the origin of a new species often takes thousands of generations.
Summer 2020 outside of Troy, Dr. Gilbert observed an unusual change in her yard which is surrounded by woods and fairly close to a state road (not huge, 2 lanes but with traffic). By the end of June, the chipmunk and squirrel populations soared, the squirrels were small and skinny whose tails were very thin rather than fluffy. The birds began to stay more in the woods rather than coming to the feeders, and the hawk came more often to the backyard. Note too that a bear passed through at the edge of the yard, but the normal fox pair were not around. Based on these observations and what you have learned, choose the one best explanation for this series of events in this local ecosystem.
The bear is not the keystone species of this ecosystem although large. The fox pair is the keystone species for this habitat. The fox pair may have been killed by cars on the road resulting in the increase in chipmunks and squirrels. The keystone species failed to keep the squirrel population culled so that all survived rather than the most fit.
Females in many species often choose to mate with males having exaggerated traits, like the peacock's tail because
These secondary sexual characteristics are indicators of fitness, i.e., good genes and therefore an increased survival of the chicks.
The Asian Clam is an invasive species at Lake George that was discovered by Dr. Jeremy Farrell in August 2010. They are tiny but pose a significant threat. What is the one incorrect choice below?
They are at the early detection phase of the management of invasive species table.
The Asian Clam is an invasive species at Lake George that was discovered by Dr. Jeremy Farrell in August 2010. They are tiny but pose a significant threat.
They excrete high concentrations of nutrients that drive growth of algae. They form mats of sharp shells in shallow sandy areas and impact waders & swimmers. They create localized calcium-rich environments that are more friendly to other invasive species suchas zebra mussels. They are at the prevention/eradication stage of the management of invasive species table.
When did prokaryotes emerge?
Archaean Eon, ~3.8-3.5 BYA
Infectious diseases that can be specifically transmitted from other vertebrate animals to humans are called
zoonotic diseases
The ENCODE Project revealed new insights about the human genome. Identify the incorrect answers.
~80% of the genome encodes proteins. The organization of the human genome is similar to the bacterial genome. The results do not require validation. >80% of the human genome could not be explained; it had no biochemical function
The first level of an energy pyramid is always occupied by
the primary producers (autotrophs)
Vitamin D-resistant rickets is an X-linked dominant bone disorder. A man with this form of rickets marries a normal woman. What proportion of the couple's sons is expected to have vitamin D-resistant rickets?
0%
During DNA replication, one DNA strand is copied to make a new DNA molecule composed of two DNA strands. This new DNA contains
50% of the parent DNA.
During DNA replication, one DNA strand is copied to make a new DNA molecule composed of two DNA strands. This new DNA molecules contains
50% of the parent DNA.
What percent of energy is lost at each level in the food chain?
90%
The following are common characteristics of eukaryotic cells
:Common traits include intracellular membranes, at least one nucleus, complex cytoplasm with organelles such as mitochondria and also chloroplasts in plants. All cells share ~500 cellular metabolic reactions with many interconnections. All eukaryotic cells exhibit intracellular motility. The cell structure can vary widely.
Epigenetics refers to
A change in gene expression without a change in DNA base sequence.
Cancer has been described by each of the following. Which of the following is no longer valid?
A disease whose oncogenic signature is specific for the tissue affected.
What is CRISPR/Cas9? Identify the one incorrect answer.
A method of DNA sequencing
The following statements are true about Zika
A. aegypti is unusual in that it thrives in urban locations and not the wild. Zika like dengue are both transmitted by Aedes aegypti. The Zika virus is a single-stranded RNA virus. Zika infection resulted in a startling increase of microcephaly of the fetus of pregnant women.
A mouse with the genotype AaMMzz will have the same phenotype as a mouse with the genotype
AAMmzz
Aside from Charles Darwin, who independently conceived of evolution by natural section?
Alfred Russel Wallace
We have learned the following from Cancer Genomics Projects except for the following one statement that is incorrect.
All breast cancer patients have the same oncogenic signature.
Over the past 10 years we have learned a great deal about cancer through genomics projects such as The Cancer Genome Atlas (TCGA) Project. Which one of the following is incorrect?
All breast cancers show the same oncogenic signature.
We have learned the following from Cancer Genomics Projects
All cancer patients do not respond to the same chemotherapy or treatment plan. Most cancers are caused by 2-8 sequential alterations over 20-30 years. A large percentage of epithelial cancers can result from whole chromosome shattering orchromothripsis. Mary Claire King was the first to show that breast cancer can be inherited.
There is the need for differential gene expression in humans because of one of the following. Identify the one correct answer.
All cells contain the same genotype.
The group known as Anthropoids include which of the following?
All primates that are monkeys or apes.
Autism is a complicated genetic disorder. Identify the one false statement.
Autism is a disease of elderly populations similar to Alzheimer's disease.
Mary Claire King in 1990 identified the gene associated with increased risk of breast cancer. Based on her initial work, we now know the following
BRCA1 and/or BRCA2 mutations increase the risk for breast cancer. Dr. King developed the BROCA diagnostic test in 2015, which can screen for 50-60 genes in patients suspected of a predisposition to hereditary cancers. BRCA1 is localized to chromosome 17. BRCA1 and BRCA2 encode for proteins involved in DNA repair.
Technological advances to manipulate gene expression include which one of the following?
CRISPR-Cas9
Jennifer Doudna and Emmanuelle Charpentier received the 2020 Nobel Prize in Chemistry. The following statements are accurate except one. Identify the one inaccurate statement.
CRISPR-Cas9 was based on technology that resulted from the ENCODE Project.
Clay was important for the emergence of life because of the following:
Clay was a scaffold for chemistry to occur.
Ecosystems are complex dynamic systems. They are characterized by all of the following statements
Computational modeling is now used to test hypotheses and design experiments to better understand the ecosystem. Numbers, biomass, and interactions among the species are constantly in flux as well as the physical environment in which the system is embedded. The ecosystem food web shows a snapshot at one particular time. Ecosystems exhibit high dimensionality.
There is strong evidence that the Neanderthals and Denisovans interbred with one or more of our Homo sapiens ancestors. The most convincing evidence is
DNA analysis identified genes that were transferred from the Neanderthals & Denisovans that provided adaptive advantages for our ancestors and still present today.
Jimmy Smith's parents have normal hearing. However, Jimmy has an inherited allele for deafness. Deafness is a recessive trait that is associated with an abnormal allele d. The allele at this locus, associated with normal hearing is D. Jimmy's parents could have which of the following genotypes?
Dd and Dd
The Clean Air Act was passed in 1970 and during the 30 years since then, there have been many positive impacts. Based on the following graph, what is your assessment of the benefits.
Decrease in ozone, sulfur dioxide, carbon monoxide, atmospheric fine particles, and lead.
The take-home message from Project Drawdown was that there are many solutions that are already available to decrease global warming. Of the following, which is mostly likely to be attainable and to have a significant impact by 2030?
Decrease methane emissions by 1/3 by 2030. Focus on alternative methods to generate electricity including onshore wind turbines, utility-scale solar photovoltaics, and distributed photovoltaics. Reduce food waste and convert to plant-rich diets. Establish tree plantations on degraded land and restore temperate forests.
What have been the successes from the Human Genome Project? Identify the correct answer(s).
Development of new technologies for DNA sequencing and analysis that have enhanced the speed and decreased the cost. Launch of the 10K Genome Project. Development of new protocols based on DNA analysis such as testing for genetic diseases using blood from the pregnant woman rather than amniocentesis. Understanding cancer and rare genetic diseases.
The figures below are histograms of the distribution of Geospirza fortis beak widths/depths observed by Rosemary & Peter Grant in 1976 and in 1978 on Daphne Major Island. These results are indicative of
Directional selection.
Symbiotic mutualistic relationships can have the following benefits. Identify the one choice that explains the elephant foot yam plant-beetle relationship.
Dispersive benefits
What is eutrophication?
Excessive nutrients in water causing excess algal growth
Ecosystems are complex dynamic systems. They are characterized by all of the following statements except one. Choose the one incorrect statement.
Ecosystems tend to be stable on long temporal time scales because of recycling and regeneration.
When did the emergence of multicellular eukaryotes first occur?
Ediacaran period, 0.6-0.5 BYA
The following are statements about emergent complexity. Choose the one incorrect answer.
Emergent systems are at thermodynamic equilibrium.
Why was aerobic respiration a requirement for the emergence of eukaryotes?
Eukaryotic cells are much more complex than prokaryotes, and greater amounts of energy are required for eukaryotic metabolism.
Which of the following is NOT consistent with natural selection?
Every member of the population is exactly the same.
Which of the following statements is NOT consistent with Darwin's theory of natural selection?
Evolution is goal oriented to lead to perfectly adapted organisms.
Thirty people are selected for a long-term mission to colonize a planet many light-years away from Earth. The mission is successful, and the population rapidly grows to several hundred individuals. However, certain genetic diseases are unusually common in this group, and the group's gene pool is quite different from the population on Earth that they left behind. Which of the following phenomena has left its mark on this population?
Founder Effect
What early evidence prior to 1953 supported the hypothesis of Watson and Crick that DNA carried the information for genetic inheritance?
Frederick Griffith's experiments when he was trying to develop a vaccine to pathogenic pneumonia.
Which of the following traits do humans share with all other species in the order Primates?
Grasping hand Binocular vision Larger brain Parental care & sociality
James Allison was awarded the 2018 Nobel Prize in Physiology or Medicine for the following medical breakthroughs. Which statement below is false.
He identified immune checkpoint inhibitors that could potentially treat COVID-19.
Regulation of gene expression at the transcriptional level for eukaryotes include all of the following
Histone and DNA methylation Circadian clock regulation Transcription factors that recognize specific DNA sequences DNA packing
Excluding admixture from breeding with other species which of the following is the immediate predecessor of modern humans?
Homo sapiens idaltu
Studies of DNA support which of the following?
Homo sapiens originated in Africa
The general hypotheses that account for the disappearance of the Neanderthals include all but one. Which of the following is NOT favored as a hypothesis?
Humans annihilated the Neanderthals.
How many species are there? Choose the one best answer.
In 1998, Sir Robert May concluded that scientists still do not have a good estimate of how many species exist on our planet.
Mary Claire King in 1990 identified the gene associated with increased risk of breast cancer. Based on her initial work, we now know the following except one incorrect statement.
In 2015, Myriad Genetics argued before the Supreme Court that naturally occurring DNA should not be patent eligible.
Neil Shubin & colleagues made one of the greatest paleontological discoveries of all time. Whywas the discovery of Tiktaalik so important?
It explained the transition from fish in the water to vertebrates that could walk on land.
The discovery of the Burgess Shale deposits in the Canadian Rockies of British Columbia, Canada resolved Charles Darwin's dilemma that some species seemed to lack ancestors. Why was this discovery important?
It revealed fossil beds of soft-part imprints and documented the ancestral life forms of the Cambrian explosion.
Why was the discovery of PDS 70b so important?
It was the first newly forming planet to be directly imaged and is providing evidence to understand the formation of earth.
Neil Shubin & colleagues made one of the greatest paleontological discoveries of all time. Why was the discovery of Tiktaalik so important?
It was the missing ancestral link between fish and tetrapods and explained the transition from fish in the water to vertebrates that could walk on land.
Which of the following is true about double-stranded DNA?
Its 3-D conformation is quite different from RNA's 3D conformation.
Erwin Schrödinger proposed that life could be understood in terms of the laws of physics and chemistry. What was the one concept that he proposed that enabled living organisms to evade the decay to thermodynamic equilibrium?
Life is not a closed system and constantly receiving energy from the sun to sustain its metabolism.
Genetic changes that underlie oncogenesis alter fundamental properties of cells including all of the following except one. Which one is incorrect?
Malignant cells are more highly oxygenated and do not migrate toward a blood supply.
Why is the inheritance of so many traits difficult to explain using only Mendel's view of genetics?
Mendel was correct for the traits he investigated, but his principles must be extended (not discarded) to explain more complex patterns of inheritance.
Studies of different species of warbles that live in Vermont coniferous forests have shown that to avoid conflict, the species nest and forage at different heights of the trees. This is known as
Microhabitat partitioning
What concept did the video on the Christmas Island crabs emphasize?
More offspring will be produced than can possibly survive.
Mechanisms that provide genetic variation over a few generations include the following except one. Which of the following is false?
Mutations.
The modern view of nature is that
Nature is never at equilibrium.
As global temperatures continue to rise, which biome will most likely replace arctic tundra?
Northern Coniferous Forest (Taiga)
Banded iron formations arise from
O2 reacting with iron, causing it to rust out of the oceans about 2.4 BYA.
The following are true about Coronaviruses.
Of the 7 known coronaviruses, SARS-CoV-2, SARS, and MERS are considered zoonotic. Four of the coronaviruses are considered endemic to people. The SARS-CoV-2 virus is a single-stranded RNA virus. There are 7 known coronaviruses identified to date including SARS-CoV-2.
An important structural feature of a DNA molecule is that the two strands are anti-parallel. The result of the anti-parallel direction of the DNA strand means that:
One strand can be made continuously while the complementary strand is made in smaller pieces that are joined together later.
"Count Me In" was established in 2018 as a nonprofit organization committed to advancing patient-partnered research with support from the Broad Institute, Emerson Collective, Dana-Faber Cancer Institute, and the Biden Cancer Initiative. Their approach is based on the correct statement below.
Only through very large data sets can identification of mutations common to a particular cancer group be correlated with a specific treatment approach. In this initiative, there is an increased focus of including men and women, people of all ethnicities, and people of color. The goal is not just to have a genome data base but to include saliva, blood, and stored tumor samples in addition to clinical information to discover new and important patterns in cancer progression and response to treatment not presently known. Each cancer has a specific oncogenic signature, and therefore the medical treatment must be tailored for the patient.
The following are true about the Phosphorus Cycle except one choice. Identify the one that is false.
Phosphates transferred from terrestrial to aquatic ecosystems are able to recycle in the soil on the same time scale such that phosphates in the aquatic system do not increase.
The following are true about the Phosphorus Cycle
Plants can convert phosphate to organic molecules. The phosphorus cycle is dependent on the weathering of rock. The phosphorus cycle occurs in the soil. Phosphorus can be transferred from the soil to the water.
What is the main way that living organisms contribute to the Global Water Cycle?
Plants move water from the ground to the atmosphere via transpiration.
A temperate coastal marsh can provide the following services that directly benefit our well-being.
Protect shoreline from erosion, severe storms, and rising seas. Regulate climate and air quality. Recycle nutrients, decompose wastes, and recharge freshwater aquifers. Act as pollution filters.
What is some evidence that RNA is the original self-replicating molecule?
RNA is required for DNA replication.
Mechanisms that provide genetic variation over a few generations include the following except one. Which of the following is true?
Random and independent orientation of chromosomes at metaphase I. Fertilization is random. Homologous chromosomes carry different versions of genes. Crossing over at Prophase I of meiosis.
The ENCODE Project revealed new insights about the human genome. Identify the one correct answer.
Recognition that evolutionary change occurs through sequences that alter gene regulation.
The following map shows the more recent increase in average temperature in ºC for 2005-2015 relative to 1951-1980. Note the color scale as it relates to temperature increase.
Taiga and Tundra
The Cambrian Period was characterized by unprecedented proliferation of species & phyla including an explosion of animal diversity. Identify the one INCORRECT statement below.
The Cambrian Period occurred during the late Hadean eon.
Identify the incorrect answers below about Ebola, the disease.
The Ebola virus showed the same genotype in patients from Guinea, Liberia, and Sierra Leone. Ebola like H1N1 is an airborne disease and spread accordingly. The genome of the Ebola virus from the many patients infected in Guinea, Liberia, and Sierra Leone showed few mutations.
The following statements are related to vaccine development for SARS-CoV-2 except one. Identify the one incorrect answer.
The FDA only approved mRNA vaccines for emergency use.
The following are true about Coronaviruses except one incorrect response below. Identify it.
The SARS-CoV-2 genome contains 8 RNA strands.
Which of the following was a novel deduction that Watson and Crick were able to make about DNA based on Rosalind Franklin's X-ray diffraction data, i.e., Photo 51?
The consistent width of DNA led them to conclude that purines must base-pair with pyrimidines.
Why do the seasons of the year occur, i.e., why is it warmer during the summer than in the winter?
The earth's axis of rotation is tilted relative to the plane of the earth's orbit around the sun.
Why do the seasons of the year occur, i.e., why is it warmer in the Northern Hemisphere during the summer than in the winter?
The earth's axis of rotation is tilted relative to the plane of the earth's orbit around the sun.
Which of the following is the best definition of the term biosphere?
The entire portion of Earth inhabited by life from several kilometers above Earth to the depths of the ocean.
Endosymbiosis explains how eukaryotes arose from a symbiotic relationship between two types of cells. Which one of the following statements is true?
The host cell was of archaeal lineage and the endosymbiont was from a bacterial lineage.
The Alaskan Kelp Ecosystem collapsed in the 1990s because of all of the following except one Incorrect statement. Choose the false statement.
The kelp ecosystem recovered from collapse.
Robert Paine and James Estee tested the hypothesis that a healthy ecosystem is regulated from the top down as well as from the bottom up. Choose the one best statement.
The kelp forest was maintained as a healthy ecosystem because the sea otter, the keystone species, controlled the sea urchin population.
Which of the following is false regarding the lac operon in E. coli?
The operon is switched off in the presence of lactose in the growth medium.
What have been the successes from the Human Genome Project? Identify the one incorrect answer.
The shotgun approach was fast but not reliable
Which of the following describes the greenhouse effect?
The sun's heat is trapped in a planet's lower atmosphere because the atmosphere is more transparent to the sun's visible light relative to the infrared radiation emitted from earth's surface.
Robert Ballard in 1977 aboard a deep-water submarine made one of the most important discoveries of our time. What was the discovery?
The waters around the hydrothermal vents >8,000 feet down in the Pacific Ocean were teaming with life.
What was one major surprise from the Human Genome Project published in 2018?
There are more RNA-encoding genes than protein-encoding genes.
Count Me In was established in 2018 as a nonprofit organization committed to advancing patient-partnered research with support from the Broad Institute, Emerson Collective, Dana-Farber Cancer Institute, and the Biden Cancer Initiative. The approach is based on the following statements except one. Choose the one incorrect answer.
There is not a need for this approach because our physicians have access to all of our medical results.
Which of the following is true about Neanderthals ( Homo neanderthalensis)?
They had larger brains than modern humans.
Why are so many emerging infectious diseases linked to RNA viruses?
They lack the DNA proofreading mechanisms
Jennifer Doudna and Emmanuelle Charpentier received the 2020 Nobel Prize in Chemistry. The following statements are accurate
They received the Nobel Prize for developing a new technology that can cleave target DNA with remarkable precision, and then add, remove, or modify DNA with precision. CRISPR-Cas9 was based on a mechanism that bacteria use to defend against bacteriophages. CRISPR is presently the simplest, most versatile, and precise method of genetic manipulation. CRISPR-based genome editing offers exciting promise for curing human disease, advancing agriculture, and eradicating pests that carry disease.
The North American Pronghorn far outraces any predators remaining on the North American continent. If maintaining this speed means bearing fewer offspring, which of the following is the most likely to happen given enough time?
This species will slow down.
The goal of the 2021 Vertebrate Genome Project is
To generate near error-free reference genome assemblies of 70,000 extant vertebrate species.
Which statement about viruses is NOT true?
Viral genes do not code for proteins. All viral genomes are composed of RNA. Viruses infect eukaryotic organisms but not prokaryotes.
The fossil record shows that anatomically, modern Homo sapiens evolved at least 200,000 years ago and brain shape became comparable to ours today at least 100,000 years ago. Yet, the cave art, tools, and artefacts support the hypothesis that modern complex technology and culture evolved more slowly and became evident 50,000-60,000 years ago. Which of the following do not represent behavioral modernity?
We are arboreal and must hunt for our food
It is well known that the fox and hare exist in a predator-prey relationship. The data in the graph can be best interpreted as follows:
When the fox population suddenly decreased because of disease, the hare population dramatically increased.
Autosomal disorders cannot be caused by
X-linked disorders
A population is defined as
a group of individuals of the same species that live in the same area and interbreed.
Broccoli, cabbages, and Brussels sprouts all descend from the same wild mustard and can still interbreed. These varieties were most likely produced by
artificial selection.
Population size is dependent upon
abiotic factors food prey-predator relationships habitat
Which of the following allows for a single gene to encode for more than one polypeptide?
alternative mRNA splicing.
In many organisms including humans, chromosomes are found in homologous pairs. Homologous chromosomes
are identical in the arrangement of their genes, but some versions of the genes (alleles) may differ between the chromosomes.
Organisms around the hydrothermal vents are called
chemotrophic
Of the world's biomes, which are found on the North America continent?
deciduous forest temperate grassland tundra taiga
The stages of management for invasive species include the following: prevention, early detection, eradication, containment, and long-term control. For the Asian giant hornet, where are we?
early detection & eradication
Concerning a continuous biological trait, disruptive selection
favors both of the extremes.
Of the following, what is the greenhouse gas of most concern?
global warming and climate change
What do we need to know or do to predict an epidemic or pandemic?
human to human transmission experimentally test recombinants for pathogenicity monitor viral evolution in areas of previous outbreaks interspecies transmission and potential for re-assortment of viral genome
If the temperature rises two (2) degrees above pre-industrial levels, which of the following is NOT predicted to occur.
increases in the amount of freshwater
What two important words define a complex dynamic ecosystem?
interdependent and connected
A genome graph
is a network of DNA sequences typically from 1,000 or more individuals.
The Gulf Stream
is the current responsible for maintaining a warm climate in Europe and eastern North America
Regulation of gene expression at the transcriptional level for eukaryotes include all but one of the following. Choose the incorrect answer.
mRNA splicing
Predation can lead to adaptations in prey species to enhance their survival through a process called natural selection. Examples include
mechanical appendages chemical defenses hard shells camouflage
X-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.
A researcher treats cells with Taxol, an inhibitor that stabilizes the spindle microtubules. This treatment would trap the cells in which stage of mitosis?
metaphase
The statements below are true for the role of microRNA gene expression with the exception of one incorrect answer. Identify the incorrect answer.
microRNAs encode for proteins.
Biodiversity is impacted by
number of producer species latitude habitat size consistent rainfall and precipitation
The dodder plant is in a symbiotic relationship with other plants because it can send out shoots that entwine host plants and rapidly paralyze the host and other plants nearby. Moreover, dodder plants do not have chlorophyll. What type of interspecific relationship is this?
parasitic
Over the last 25 years, there has been a significant increase in emerging infectious diseases world-wide that have had a significant impact on human health. The contributing factors include all but one of the following. Identify the incorrect
refusal to be vaccinated.
The spiny water flea in Lake George is an invasive species that
restructures the food web.
A change in a biome from a large undisturbed area to an area that is substantially fragmented can
result in a decrease in species diversity.
The 3-D structure of RNA is very different from DNA because of the following
the 2'-hydroxyl (-OH) makes RNA more chemically reactive. a series of ribonucleotides connected by covalent bonds. the base pairing prevents formation of an anti-parallel double helix. the nitrogenous base uracil.
The earliest theory that connects carbon dioxide emissions with an increase in global temperature came from
the chemist Svante Arrhenius around 1900, for which he received the Nobel prize.
The Gross Primary Production (GPP) of an ecosystem is
the conversion of solar energy to chemical energy as organic compounds by photosynthesis.
Australopithecus afarensis ( Lucy's species) is important in the human lineage because this species is
the earliest known biped of the human lineage.
Net Primary Production (NPP) of an ecosystem is
the energy remaining after autotrophs have met their own energetic needs. the energy stored by producers as chemical energy that can be released at a later time. calculated as GPP minus the respiration of the producers = NPP. measured in units of gC/m2/yr.
Scientists hypothesize that a major factor promoting the adaptive radiation of mammals was probably
the mass extinction of the dinosaurs
What is the definition of biodiversity?
the number and variety of species in ecological systems at local to global scales
Which best describes Ida (Darwinius masillae)?
the possible missing link between early primates and the modern looking primates.
According to scientific consensus the primary cause of recent global warming is
the production of greenhouse gases by human activities.
The first level of an energy pyramid is always occupied
the sun or chemical energy source
Zircons are important because
their appearance in the geological record is the earliest evidence of liquid water on Earth.