Unit 2 Test Study Guide (Key) (2).pdf

Key Name: ____________________________________________________ Date: ________________ Unit 2 Test Review 1) From smallest to largest, list the levels of ecological organization. • Individual __________________________________ • Population __________________________________ • Community _______...

Key Name: ____________________________________________________ Date: ________________ Unit 2 Test Review 1) From smallest to largest, list the levels of ecological organization. • Individual __________________________________ • Population __________________________________ • Community __________________________________ • Ecosystem __________________________________ • Biosphere __________________________________ population 2) Several organisms of the same species would be considered a ______________________. ecosystem 3) An __________________ includes all living (biotic) factors and nonliving (abiotic) factors in a physical environment. community 4) A _____________________ includes all the different populations in a particular area. 5) Describe the difference between an Earth’s ecosystems and its biosphere. An ecosystem includes all the biotic and abiotic factors in a physical environment within a particular area. The biosphere includes all parts (ecosystems) that host life on Earth. B 6) Which group of pictures represents abiotic factors? __________ A B habitat 7) The specific environment in which an organism lives is considered its _______________. density 8) Population ________________ describes how crowded a population is. 9) Describe how competition for resources, predation, and the spread of disease change as a population becomes denser. As numbers in a population increase, and become more dense, competition for limited resources and predation increase. Disease can also spread faster when populations are crowded and in close proximity. 10) Label the following ways in which populations are distributed. Random __________________ Uniform __________________ Clumped __________________ 11) Why is clumped distribution most commonly found in nature? Populations often clump together around resources (food & water). _______________________________________________________________________________________ 12) An age structure pyramid that is very wide at the bottom and narrows sharply as you move up, displays a growing ______________ population. 13) If you have an aging population, and not many organisms in their reproductive ages, this population would declining most likely be labeled ______________. 14) List the 5 things an age structure diagram displays. Gender • __________________________________ • Reproductive Stage __________________________________ • Age __________________________________ • Sex Ratios __________________________________ • Future Growth __________________________________ Sex _________ ratios 15) ______ explain the proportion of males to females. 16) Using the image below, describe the difference between immigration and emigration. Emigration occurs when an individual leaves a population. Immigration occurs when an individual enters a population. Migration 17) ____________________ is the seasonal movement of individuals into and out of an area, creating population fluctuations. 18) Using the survivorship curve below, describe how the likelihood of death varies with age between Type I, II, and III organisms. Type I: Offspring, in their younger years, have a HIGH rate of survival. LARGE numbers of these organisms live into old age. Type II: There is equal death among each age interval. Type III: Offspring, in their younger years, have a LOW rate of survival. SMALL numbers of these organisms live into old age. 19) Using what you know about survivorship curves, explain why it is beneficial for type III organisms to have a very high biotic potential, and why type I organisms do not. The vast majority of Type III organisms die very young, so they must reproduce often and in high numbers to ensure that enough young make it to adulthood and reproduce. This is why their biotic potential is so high. Large numbers of Type I organisms survive to adulthood, therefor each offspring has a high chance of reproducing. This is why their biotic potential is so much lower. 20) Using the image below, formulate an equation that can be used to calculate a population’s growth. (Births + Immigration) - (Deaths + Emigration) = Population Growth _______________________________________________________________________________________ Exponential 21) _________________ growth describes a population increasing by a fixed percentage every year. This rarely type of growth __________ last long. 22) Why doesn’t the growth, described in question #21, last forever? There are a finite amount of resources available in nature, and every population eventually reaches the point where no additional organisms can be supported. There are also predators and diseases that can limit growth. limiting factors 23) Factors such as predation, water, and habitat are examples of ____________ ____________, which slow a population’s growth and determine an organism’s carrying capacity. 24) Label each of the graphs as either logistic or exponential. exponential ________________________ logistic ________________________ 25) What is the basic difference between density dependent and density independent limiting factors. (DD) limiting power increases as density increases. (DI) limiting power doesn't depend on the population density. _______________________________________________________________________________________ 26) Explains why predation and disease are density dependent limiting factors. They are density dependent because both predation and disease involve biotic (living) factors, and as the density increases both the rate of predation and spread of disease will increase. 27) Explain why water and temperature are density independent limiting factors. They are density independent because both water and temperature are abiotic (nonliving) factors, and there ability to limit growth doesn't depend on how large the population is. Biotic potential 28) ___________ _______________ describes an organism’s maximum ability to produce offspring in ideal conditions. 29) Why are organisms, with high biotic potential, able to recover from population decline? They are able to reproduce rapidly and produce high numbers of offspring with each reproductive cycle. 30) How does an organisms’ niche and habitat differ? An organisms habitat is the specific environment which it lives in. Its niche, on the other hand, describes an organisms resource use and functional role in the environment. partitioning 31) The image below displays resource ___________________, which organisms utilize to reduce competition _______________. Use the image below to help you explain this process. Each bird is using the tree to acquire food, but they are all using different methods. This is partitioning resources, it reduces competition and allows for more successful species. Character displacement 32) ___________________ __________________ occurs when the evolution of physical characteristics among competing species. Explain how the image details this process. These finches all inhabit the same area, yet they all thrive. This is due to character displacement (the size and shape of each beak). Each bird's beak has evolved, and they have become specialized feeders. Again, this is to reduce competition. photosynthesis or from producers sun 33) Primary ____________________ capture energy from the ________ (________________) chemicals chemosythesis ______________ (_____________________) and store it in the bonds of sugars, making it available to the rest of the community. 34) Label the organism that utilizes chemosynthesis and the one that utilizes photosynthesis. chemosynthesis photosynthesis energy nutrients 35) Organisms that rely on other organisms for ___________ and _____________ are classified as consumers _________________. Detritivores decomposers 36) __________________ and _________________ are consumers that feed on dead and decaying organisms. Provide three examples of these organisms. • vulture mushrooms (fungi) earthworms _________________________, _________________________, _________________________ 37) Producers use sunlight or chemicals to create the energy they need. Consumers can’t do this, instead they cellular respiration utilize __________________ ___________________ in order create the energy they need. 38) Using the 10% Rule, explain how energy is transferred in an ecosystem. Only about 10% of the energy available at any trophic level is passed to the next; most of the energy is lost to the environment as heat and used for life processes. trophic level 39) The rank that an organism occupies in a pyramid of energy is its ____________ ___________. 40) Correctly label the Pyramid of Energy below. Trophic Level 105.3 kCal Energy from level before it ________________ 3rd Consumer ___________ Trophic Level 2nd Consumer ___________ Trophic Level 1st Consumer ___________ Trophic Level Producers ___________ biomass 41) All the living tissue in an ecosystem is its ______________. 1053.06 kCal Energy from level before it ________________ 10530.6 kCal Energy from level before it __________ 105,306 kCal 42) Using the image below as an example, explain why a pyramid shape was chosen to display the amount of energy and biomass available at each trophic level. In every ecosystem the greatest amount of biomass and energy is located in the producers, thus they are at the base. The 10% rule states that only 10% of the energy at one trophic level is available to the next. So a pyramid is a perfect shape to display the decrease biomass and energy as you move up trophic levels. 43) Label the images below as either a food web or food chain. (Small Box) Explain why ecologists gain a better understanding of an ecosystem by studying food webs, not food chains. (Large Box) Describe what would most likely happen to the populations of the Large Piscivorous Fish, Phytoplankton, Bivalves, and Bald Eagles If the small Planktivorous Fish population decreased by 75% Food Web Food Chain Food webs give a complete understanding of all the feeding relationships in an ecosystem. Food chains, on the other hand, only provide a partial understanding. Food webs also allow one to understand all the direct and indirect relationships that exist. Large Piscivorous Fish: There would be a dramatic decrease in the population size of this organism due to a 75% reduction in its only food source. Phytoplankton:There would be a slight increase in the population size of this organism due to the fact that one of its predators have decreased in numbers, but it still has two other predators. Bivalves: There would most likely be no change in the population size of this organism. This is because there will be more phytoplankton for it to eat, but more Sea Ducks will prey on them. Bald Eagle: There will be a moderate decrease in the population size of this organism. This is because half of their food source has lost 75% of their prey. Keystone 44) _____________ species have strong and/or wide-reaching effects on a community. Their removal can dramatically ____________ impact a community. Using the image below, explain why the Sea otter is labeled a keystone species. The sea otter preys on the sea urchin, keeping their numbers in check. If the sea otter was gone, the urchin would destroy the kelp. The kelp is a critical part of the ecosystem for every other organism. So for this reason the otters presence or absence effects every organism in the ecosystem. Primary 45) Below is an image of __________________ succession. The red circle is where you would find pioneer lichens moss The yellow circle is what is known as the _______________ species such as ____________ and ________. climax ______________ community. Secondary soil 46) Below is an image of ___________________ succession. Due to the presence of ___________ this type of succession occurs much faster _____________ than primary succession. 47) Explain the importance of pioneer species, and how they prepare the ecosystem for all future life. Pioneer species, such as lichens and moss prepare the ecosystem for all other life. They help to break down rock, and when they die they add organic matter. The broken down rock and organic matter creates soil. As the soil becomes deeper and more nutrient dense, larger more complex organisms are established. 48) Using the image as an example, explain succession in water (pond succession). The picture to the far left shows the pond, at the begining of succession. It begins to fill with life, but there is very little vegetation or sediments in the pond. The picture in the middle shows the next step of succession. There is now vegetation covering the bottom, large amounts of sediments and decayed organisms have filled the bottom and the pond is now much more shallow. The picture on the right now displays how sediments have filled almost all of the pond, the area is covered with vegetation, and the pond is now a swamp. 49) Using the Zebra and Quagga mussels we learned about, explain why nonnative species become labeled as invasive species. These species, from Eastern Europe, have made their way to North America and are now considered invasive. They are classified as so because they out-compete native organisms for resources, resulting in a decrease in native populations. They also cause economic problems when the attach to pipes and motors, disrupting the flow of water and destroying the motors on boats.