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Bell Ringer – AP Practice Bell Ringer – AP Practice 1) Reasons that the population size of an exotic species often grows rapidly when the species is introduced in a new environment include which of the following? i. The exotic species is resistant to pesticides ii. There is a large, underutilized food source in the new environment iii. The exotic species has few natural predators in the new environment a) i only b) ii only c) i and iii only d) ii and iii only e) i, ii and iii 2) Which answer below explains a trophic cascade from the food chain? a) The frog acquires energy from eating grasshoppers b) The population of snakes is dependent upon the population of frogs as a food source c) The population of grasshoppers is related to the population of hawks d) Based upon the 10% rule, the hawk will only get 0.01% of the original amount of energy. 3) A keystone species… a) Has the largest population abundance b) Has the largest habitat c) Has a large influence upon energy movement in an ecosystem d) Forms the base trophic level e) A and C 4) An aquifer is … a) The entire area of land from which water drains b) The uppermost portion of an underground water source c) An underground source of water found in a sponge -like layer of rock and soil d) All the water found on the surface of the earth, including salt water e) All the life found on earth Bottle Ecosystem Day 1 Objectives – Day 1 • Cut all bottles to size and label • Prepare the aquatic chamber Biogeochemical Cycles pgs 186-198 Biogeochemical Cycles • All nutrients move through ecosystems by various processes, known collectively as biogeochemical cycles. • The most important biogeochemical cycles include: – Hydrologic cycle – Carbon cycle – Nitrogen cycle – Phosphorus Cycle The Hydrologic Cycle • Water is vital to life on earth and is involved in nearly every ecosystem and biogeochemical cycle. • The Hydrologic Cycle describes how water moves through an ecosystem. • The movement of water is dependent upon chemical changes which allow it to be either a solid, liquid or gas. Evaporation and Transpiration • Most water on earth is found within reservoirs (such as the ocean). • Liquid water moves from these reservoirs into the atmosphere (in gaseous form) through the process of evaporation . Evaporation and Transpiration • Evaporation rates are increased with - high temperatures - high winds - greater exposure (cleared areas) Evaporation and Transpiration • Water also enters the atmosphere through the process of transpiration – the release of water vapor by plants through their leaves. Precipitation and Runoff • Water vapor in the atmosphere condenses to form clouds – eventually coming back to earth in the form of precipitation . Precipitation and Runoff • Some precipitation is taken up by plants or used by animals, but much of it flows as runoff into streams, rivers, etc. – eventually reaching the ocean again. Groundwater • Water from aquifers reenters the hydrologic cycle as humans extract water for drinking or as water tables rise to the surface, allowing water to be evaporated or to runoff into larger sources. Illustrate a simple example of the Hydrologic Cycle (label evaporation, transpiration, precipitation, runoff and aquifers) Bell Ringer 1) In the diagram of the water cycle below, “A” is _______, “B” is ________, “C” is ________, and “E” is ______ Bell Ringer 2) In the water cycle diagram, “F” is representing a ____________, while “D” is representing an ____________ Bell Ringer – AP Practice 3) All of the following are heterotrophs except… a) Vulture b) Bacteria c) Moss d) Human e) Mushroom 4) Which of the following trophic levels has the most biomass? a) Producer b) Primary consumer c) Secondary consumer d) Decomposer e) Tertiary consumer Bottle Ecosystem Day 2 More Biogeochemical Cycles The Phosphorus Cycle • Phosphorus is an important nutrient, making up a key component of cell membranes and found in such important molecules as DNA, RNA, ATP and ADP. The Phosphorus Cycle • Although phosphorus is required for life processes, this nutrient is found mostly outside the body: in rocks, soil and the ocean. The Phosphorus Cycle • Unlike the other biogeochemical cycles (water, nitrogen and carbon), this cycle has no appreciable atmospheric component. • The only time phosphorus enters the atmosphere is if the wind carries the nutrients from one area to another. Step 1: Weathering • The vast majority of the earth’s phosphorus is in the form of rock and is released by weathering. • 3- Phosphate ions (PO 4 ) are released by weathering and enter water systems. Step 2: Dissolving • Phosphate ions that enter lakes or oceans settle to the bottom to form sediment – the precursor to more rock. Lack of Phosphorus • Because most phosphorus is found in rock, there is very little environmental concentrations available to organisms. • This explains why phosphorus is frequently a limiting factor for plant growth (and why it is included in most fertilizers). Step 3: Phosphorus in Living Things • Plants take up phosphorus through their roots only when phosphates are dissolved in water. • Primary consumers acquire phosphorus from water and plants, passing it on to secondary and tertiary consumers. • Phosphorus is passed out of living things through the excretion of waste – decomposers break down the waste, returning the phosphorus to the soil. Step 3: Phosphorus in Living Things Human Affects on the Phosphorus Cycle • Humans influence the P-cycle by: – Mining for phosphorus from rocks – Applying phosphorus to lawns, crops in fertilizers – Wastewater is rich in phosphates – Most detergents are high in phosphates • Excess phosphates entering waterways can lead to eutrophication, altering aquatic ecosystems. Make a Sketch of the P – Cycle Bell Ringer 1) The biggest reservoir of phosphorus is… a) The ocean b) Within rocks c) Within plants d) The atmosphere e) Within cells 2) Which answer below does NOT add phosphorus to the atmosphere? a) The use of detergents b) Human wastewater c) Mining d) Weathering e) Photosynthesis 3) Starting at a plant, put the steps of the hydrologic cycle in the correct order: Precipitation, transpiration, condensation, runoff 4) In your own words, describe the edge effect. Bottle Ecosystem Day 3 More Biogeochemical Cycles The Carbon Cycle • All living things on earth are carbon-based; this element can be found in carbohydrates, fats and proteins. • Carbon can be found all around us – from fossil fuels to DNA to plastic. Step 1 - Photosynthesis • Carbon dioxide in the atmosphere is used by plants to create sugar (glucose) through the process of photosynthesis. Step 2 – Respiration • Cellular respiration is used by all organisms (including autotrophs) to create ATP from sugar. This process releases carbon dioxide back into the atmosphere. Photo and Resp • Photosynthesis and Respiration make their own cycle – each producing products that the other process needs to begin. Carbon Storage • Some carbon used by organisms is stored within that organism, incorporated into its tissues. • Plants take in much carbon dioxide for photosynthesis – making autotrophs a major carbon reservoir. Carbon Storage • Some carbon used by organisms is stored within that organism, incorporated into its tissues. • Plants take in much carbon dioxide for photosynthesis – making autotrophs a major carbon reservoir. • Because carbon dioxide is a greenhouse gas, it is even more important that major tracts of trees and plants remain undisturbed as they have the capability of deflating the effects of global warming. Carbon Storage • Sedimentary rock is the largest carbon reservoir on earth. • As organisms die, they become sediments which, over long periods of heat and pressure, can be transformed into carbon containing rock (such as coal and limestone). Carbon Storage • Carbon molecules in the atmosphere spend a relatively short time there; carbon molecules trapped in rock may reside there for millions of years. • The burning of carbon-containing rocks (such as coal) re -releases this carbon into the atmosphere. Carbon Storage • Oceans represent the second biggest carbon reservoir. • Oceans absorb carbon-containing compounds from the atmosphere, from terrestrial runoff and from the waste of marine life. The Human Effect • An increase of carbon dioxide in the atmosphere has accelerated global climate change. • Human actions can remove carbon from reservoirs, forcing it to accumulate in the atmosphere. These actions include: – The burning of fossil fuels (coal, gasoline, etc.) – Removing vegetation/forests which taken in and store carbon dioxide. .
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