Biology

Large-scale cancer studies have found that the p53 gene is often mutated in tumor cells. In fact, the gene encoding the p53 protein is mutated in tumor cells more often than any of the other 20,000 human genes. Based on this information, why was the Bunz study important?
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Male northern elephant seals (Mirounga angustirostris) compete with one another for territories along the beach. Males defend these territories throughout the breeding season. The males that win the malemale competitions defend the "best" territories, and have access to females that stay in that territory of the beach. The females land on the beach during mating season, choosing which territory of the beach to join. They then disproportionately breed with the male that defends that area of the beach. At what point may intersexual selection occur in these elephant seals?A. when the female is swimming to the beachB. when the female leaves the beach after mating with a maleC. when the male defends his group of females against a different maleD. when the female lands on the beach and chooses her resting locationE. when the male mates with a female within his group
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Lionfish, indigenous to the Indian Ocean, have been found in the Atlantic Ocean since their accidental release in the late 20th Century. These fish feed on the same species as local snapper and grouper. They can also impact coral reef ecosystems by consuming herbivores, which keep the algae populations in check. Which statement explains why the lionfish populations continue to increase in the Atlantic and the impacts of the lionfish on marine ecosystems continue to be observed?A)Lionfish have no natural predators in the Atlantic, so there is a lack of population control for these fish.B)Lionfish have a narrow range of temperature tolerance and salinity, so they only reproduce exponentially in the Atlantic.C)Lionfish have symbiotic relationships with coral reef species that increase the populations of native and invasive species.D)Lionfish migrate to the aphotic zone of the ocean to spawn, which has no light and reduces the visibility of the eggs for parasites.
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The Dunkers are a religious group that moved from Germany to Pennsylvania in the mid-1700s. They do not marry with members outside their own immediate community. Today, the Dunkers are genetically unique and differ in gene frequencies, at many loci, from all other populations including those in their original homeland. Which of the following likely explains the genetic uniqueness of this population?A) population bottleneck and Hardy-Weinberg equilibriumB) heterozygote advantage and stabilizing selectionC) sexual selection and inbreeding depressionD) mutation and natural selectionE) founder effect and genetic drift
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What is the scientific definition of energy that relates it to work?the ability to use an applied force to make an object movethe ability to use the stored potential of an objectthe ability to use the change in temperature of an objectthe ability to use the change in direction of an object
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Webers law is most closely associated with ____. a.the just noticeable differenceb.the absolute thresholdc.sensory reductiond.sensory deprivation
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Describe the structure of a typical bone
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What causes the myosin head to move into the 'cocked' position after it is released from actin? Group of answer choices ATP binding to myosin. ATP hydrolysis into ADP and Pi on the myosin head. ADP and Pi release from the myosin head Ca2+ binding to troponin.
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Which link is missing from this food chain?O decomposerO herbivoreo producerO consumer
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Which of the following is true of both starch and cellulose? a. They are both polymers of glucose. b. They are geometric isomers of each other. c. They can both be digested by humans. d. They are both used for energy storage in plants. e. They are both structural components of the plant cell wall.
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All fungi areGroup of answer choiceseukaryotes and heterotrophic.eukaryotes and autotrophic.prokaryotes and autotrophic.prokaryotes and heterotrophic.
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What kind of evidence has recently made it necessary to assign the prokaryotes to either of two different domains, rather than assigning all prokaryotes to the same kingdomA) molecularB) behavioralC) ecologicalD) nutritionalE) anatomical
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What were some of the misconceptions people had about the cause of the flu epidemic of 1918?
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The following is an excerpt from the case study "It's All Greek to Me": "The hematologist meets with the Stamos family in the exam room. 'Mr. and Mrs. Stamos, there are some things that do not look normal in Nikoleta's blood. I am not sure of the cause, but I do know that Nikoleta's red blood cells aren't shaped correctly and they are not the right color. The red blood cells should be very red under the microscope and her red blood cells are light pink." . How did this observation lead to identifying the type of anemia exhibited by Nikoleta? A. The shape of the red blood cells suggested that they were causing blood clots. B. The shape of the red blood cells suggested that they were causing arterial plaques. C. The pale color of the red blood cells suggested they had malfunctioning hemoglobin. D. The pale color of the red blood cells suggested they had malfunctioning cell membranes.
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DNA is approximately 2.5 nmnm in length. If an average man is 5 ft 10 in.in. tall, how many DNA molecules could be stacked to extend from the ground to the top of the head of an average man?
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Which sensory receptors detect odors and tastes?A photoreceptorsB thermoreceptorsC mechanoreceptorsD chemoreceptors
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Please hurry!!How do species adapt to changing environments over time? Explain how evidence from the fossil record and from living species suggests that earth's species are related. List each type of evidence and provide an example of each.
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A dominant mutation in Drosophila called Delta causes changes in wing morphology in Delta/+ heterozygots. Homozygosity for this mutation (Delta / Delta) is lethal. In a population of 150 flies, it was determined that 60 bad normal wings and 90 had abnormal wings. a. What are the allele frequencies in this population? b. Using the allele frequencies calculated in part (a), how many total zygotes must be produced by this population in order for you to count 160 viable adults in the next generation? c. Given that there is random mating, no migration, and no mutation, and ignoring the effects of genetic drift, what are the expected numbers of the different genotypes in the next generation if 160 viable offspring of the population in part (a) are counted? d. Is this next generation at Hardy-Weinberg equilibrium? Why or why not?
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An ecological pyramid is sometimes used to show both the flow of matter and energy in an ecosystem. The pyramid narrows as matter and energy flow from the bottom to the top. Draw a conclusion about what this pyramid tells you about the energy in this ecosystem.
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In response to stress, cells in the adrenal cortex produce cortisol, a steroid hormone. Therefore, these cells would specifically exhibit large amounts of this organelle: Select one a. lysosomesb. rough ER C. smooth ER d. ribosomes e. vaults
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What percentage of the Earth's water supply is represented by water in soil and air?
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Which of the following is a radical?O H20OHH
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What is a landfill? Check all that apply.
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Scientists developed the ________ model after their studies of the fossil record revealed that some species appear quite suddenly and then remain essentially unchanged phenotypically for a long period of time.
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