Marine Science Final Exam 2025 Actual Exam Complete Questions and Verified Answers Brand New Version

Which of the following conditions is necessary for natural selection to occur? - -More organisms are born than can survive. The average female cod produces two million eggs in a single spawning; however, only about 200 of the original two million cod survive to age one. When cod reach their reproductive age of two to four years, only two of the original two million are still alive. What can you conclude about the traits of the two cod that survived? - -These two fish have strong selective pressure. In 1989, the Exxon Valdez spilled nearly 42,000,000 liters of oil into Prince William Sound, Alaska. How would this spill be classified? - -Abiotic environmental Which of the definitions below best defines biomagnification? - -A substance that increases in concentration with trophic level The following map of the Gulf of Mexico shows reported sightings of whale sharks. What explanation best describes why the highest reported sightings occur near the mouth of the Mississippi River? - -Whale sharks are filter feeders, and this area is rich in plankton due to runoff. Why are shellfish populations often a good indicator of water quality? - -Many shellfish are filter feeders that absorb toxins from the water. Which statement best describes how pollution can impact the apex predators of the marine community? - -The apex predators are impacted by pollution in the environment because they are the top of the marine food chain, where accumulation of pollution is quite great. A marine biologist explains that the salmon adapts to its environment through descent with modification. What is "descent with modification"? - -A heritable trait can cause one generation to be slightly different from another. In the Galapagos islands, larger iguanas are more successful at reproducing and have more offspring. How would the population change if larger body size also makes iguanas more vulnerable to predatory birds? - -The population would be more balanced between small, medium, and large body sizes because while larger iguanas reproduce more, smaller iguanas avoid predators better. Marine Science Marine Science What is overproduction? - -The species produces more young than can be supported by the ecosystem. What animals would you likely find in this habitat? swamp with lots of trees - -Juvenile fish and shrimp What prediction can be made about how the distribution of coral reef populations would be affected if the oceans in which they live were to experience significantly more cloudiness of the water? he coral population would decrease due to lack of sunlight. - The coral population would decrease due to lack of sunlight. The average female Atlantic cod (Gadus morhua) produces two million eggs in a single spawning. How does this relate to natural selection? - -More organisms are born than can survive. In sea horses, the female inseminates the male by inserting her oviduct into the male brooding pouch several times to ensure fertilization. After fertilization is complete, the female departs and the male attaches himself to a nearby object, and waits for the eggs to mature. How would this reproductive strategy ensure survival of the species? - -By protecting the fertilized eggs from predators The shells of some marine snails are highly variable, with some snail shells being solid colors and others having stripes. Predation by birds is a major source of mortality for the snails. Scientists studying these snails found that while 47 percent of the snail population was striped, 56 percent of the snails eaten by birds were striped. What could scientists conclude about the snails? - -Solid shell snail genes will increase in the population. The flesh-eating bacteria, Vibrio vulnificus, destroys healthy tissue. Infectious agents such as this are best classified as what kind of environmental factor? - -Pathogenic Between 1932 and 1968, a chemical factory in Japan released mercury-laden wastewater into Minamata Bay. The mercury was modified to methylmercury by bacteria living in bottom sediments. This resulted in severe mercury poisoning in over 2,000 people. Since people don't eat bottom sediments, what is the best explanation for how toxic levels of mercury ended up in affected people? - -Mercury accumulated in higher concentrations as it passed through the food chain, resulting in disease in the top-level consumers Which of the definitions below best defines a mutation? - -A change in a cell's genetic material What would be the effect on a sea turtle population after a disease has impacted a population? - -The sea turtle population would decrease because the disease would kill off individuals. Marine Science Marine Science Evaluate whether or not fish farming would have a negative impact on human health. - Fish farming is happening in the ocean environment where excess fish waste is released into the environment. This impacts wild fish that humans consume. Which of the following is an r-selected species in the ocean and why? - -Algae are an r selected species because they have a very rapid growth phase. A marine biologist explains that salmon show overproduction, which allows natural selection to work. What is "overproduction"? - -The birth of more offspring than can survive In the Galapagos islands, marine iguanas swim in salt water and vent excess salt from their nostrils. Iguanas who are more efficient at venting the salt also have more offspring. What is the term that describes this effect, when organisms with an advantage are more likely to successfully have offspring? - -Differential reproduction A group of scientists wants to test the effects of decreased oxygen levels in the water on a population of albacore. What result from this experiment would show natural selection in progress? - -Increased reproductive success of individuals who have the ability to survive a variation in oxygen levels Where would the highest density of mangrove forests be found? - -Tropical coasts The illustration shows the worldwide distribution of orcas. The dark areas are where the whales are most commonly found. What can you infer about food sources and the distribution of killer whales as seen on the map? - -Whale food sources are more concentrated in the cool waters away from the equator, so more whales tend to live there. Which environmental factor determines why coral reef populations are found only in shallow waters? - -Light is at its greatest concentrations. Which of the following is an abiotic factor that is having a negative impact on marine populations? - -The lack of oxygen in coastal waters How do wetlands abiotically help to protect the water quality of a marine ecosystem? - They filter sediments and other material from runoff. The diagram below shows a marine food chain with the amount of energy available to each trophic level in parentheses. Why does the amount of energy decrease as you move up the chain? - -Some energy is lost as heat or not consumed by organisms at the next trophic level. Marine Science Marine Science What type of model would be most useful when trying to determine the flow of energy in a marine ecosystem? - -A model that connects the higher trophic levels with the ones below them Which of the choices below is the best comparison of competition with predation? - -In competition, organisms compete directly or indirectly for space or resources. In predation, one organism directly consumes another. Some sponges produce toxins that harm other sponges. What is the best explanation for why they do this? - -They produce toxins to help them claim physical space for which they compete with other sponges. Driving cars requires gas, which is drilled from the Earth in the form of fossil fuels. What is one negative impact this could have on the ocean environment - -The drilling of fossil fuels could lead to an accident, like an oil spill, causing harm to the ocean environment. Which of the following is a large scale environmental impact caused by the shipment of materials across the world's ocean? - -The potential of waste or sewage dumping from the ships into the ocean Oil spills happen in our oceans. Some oils contain volatile organic compounds; these compounds make the oil denser. What large-scale impacts could this kind of oil spill have on the ocean environment? - -Oil that is denser will sink and have a negative impact on the ocean environment. When does a general scientific theory develop? - -When it is consistent with most or all available data Which organisms have humans genetically modified to help clean up oil spills? - Bacteria What would be a consequence to seabird biodiversity along the coasts if a major oil spill happened? - -Oily feathers would prevent them from migrating to breeding and wintering sites. Which of the following is a biotic factor that is having a negative impact on marine populations? - -Predation by invasive species What do you predict would best aid in the recovery of offshore, environmentally deteriorated seagrass communities? - -Coastal development regulations Which trophic level of a marine food chain breaks down organisms from all of the other levels? - -Decomposers Barnacles and mussels compete for space on rocks. Which of the following is another good example of an interaction that is best described as competition, not predation or Marine Science Marine Science parasitism? - -Several species of nematode worms can all live in the intestines of marine fish; the presence of one type may limit space and nutrient availability for other types. Some sponges produce toxins that harm other sponges. What is the best explanation for why they do this? - -They produce toxins to help them claim physical space for which they compete with other sponges. What is one way that people pollute groundwater? - -Using excessive amounts of fertilizers on their lawns Which of the following is a large scale environmental impact caused by the shipment of materials across the world's ocean - -The potential of waste or sewage dumping from the ships into the ocean What type of evidence could be used to convince policy makers to pass a law to help reduce overfishing, and how does this show cooperation between scientists? - Scientists could collect and combine data on fish populations all around the world to show that their populations are declining. Which organism of this marine food chain would be least affected by an oil spill due to biomagnification? - -Copepods Oil spills often kill many plants and animals in the affected area. What is the consequence of these mass die offs? - -Reduced biodiversity How can an oil spill result in a loss of biodiversity? - -Large die-offs in the affected areas reduce the number of species. A major oil spill has just happened in a near-shore environment. What prediction could be made as to why an oil spill in this area would be much more dangerous to marine life than one in the open ocean? - -An oil spill in a near-shore environment would be much more dangerous due to both marine life and humans being impacted. Near the shore children and grown adults will be on the sand and in the water. If there was an oil spill, then their health would be at risk. If someone were to get water into their nose, mouth, or eyes they would potentially get very ill. Invasive species are organisms that have been introduced to new areas and have been able to spread and reproduce. What sorts of problems can they cause? - -They compete with native species and disrupt the ecosystem. How does the largest percentage of plastic in the marine garbage patches enter the water? - -Runoff from land Marine Science Marine Science The map below shows the location of the Great Pacific Garbage Patch. Based upon the information in the map, why is it impossible to "scoop up" all of the floating plastic? - currents always move the plastic to new locations Which of the following is the primary way that recycling impacts marine biodiversity? - By recycling as much plastic as possible, it prevents waste from entering the water. Lionfish are native to the tropical waters of the Indo-Pacific. What conclusions can be made about the impact of climate change on the range of lionfish and, therefore, on biodiversity? - -As ocean temperatures have increased, the range of the lionfish has changed. As top predator, it has little competition for eating smaller fish. This reduces biodiversity. Which of the following has the greatest effect on endangered species populations? - Fisheries management zones Which valuable metals are found around hydrothermal vents? - -Copper, gold, silver Geothermal energy can be found almost anywhere on Earth but generators that are used to convert the resource into energy are expensive to build. Which of the following characteristics of renewable energy makes it so important that a community should invest in developing its geothermal activity? - -Renewable energy is better for the environment. What would be a negative impact on the environment from a large-scale mining effort in the ocean? - -The habitats of many marine animals would be disrupted. Engineers have just laid a new undersea cable. What prediction can they make about the impact this will have on the environment? - -The cable will serve as a substrate to which many invertebrates will attach. Moving water, wind, sunlight, and heat from inside the Earth are all sources of renewable energy. What is the main benefit of using this type of energy? - -The benefit of using renewable energy is that we are not burning fossil fuels. This dec