Tuesday 10/30/12 A researcher observing an ecosystem describes the amount of sunlight, precipitation, and type of soil present. Which factors is the researcher most likely describing? A. biotic factors in a forest B. biotic factors in a tundra C. abiotic factors in a prairie D. abiotic factors in an ocean C Wednesday 10/31/12 • Scientists observed that the populations of top-level consumers in a particular ecosystem were rapidly decreasing. Further studies revealed that there was also a decline in producer productivity. Which other changes did the scientists most likely observe in the ecosystem? • A. increased producer diversity • B. decreased population size at all levels • C. decreased primary consumer populations only • D. increased primary and secondary consumer diversity B. Key: A decline in the producers of an ecosystem will cause a decrease in all other organisms because the producers are responsible for converting sunlight or chemical energy into usable energy for consumers. Thursday 11/1/12 Isle Royale is located in Lake Superior. Isle Royale is home to populations of wolves and moose. The interactions between the wolves and moose, as well as the individual population sizes, have been studied since 1958. The graph shows the population sizes over time for both wolves and moose. • Isle Royale is located in Lake Superior. Isle Royale is home to populations of wolves • and moose. The interactions between the wolves and moose, as well as the individual • population sizes, have been studied since 1958. The graph shows the population sizes • over time for both wolves and moose. Describe one limiting factor for the moose population. Friday 11/2/12 Explain one likely reason why the wolf population rapidly increased between 1975 and 1980. Wednesday 11/7/12 • Predict what will happen to the moose population’s size after 1994 by describing the shape of the curve. In your answer, be sure to explain the reasoning behind your prediction. The student response correctly describes one of the limiting factors for moose on the island, logically explains that an increase in wolf population indicates an ample food supply for the wolves, and correctly predicts the shape of the curve and logically explains why the moose population might change after 1994. Thursday 11/8/12 • The diagram models how a poison bonds to the active site of an enzyme. Which function is the enzyme most likely unable to perform because of the attachment of the poison molecule? • A. the release of stored chemical energy • B. the donation of electrons to the substrate • C. the supply of activation energy for a reaction • D. the catalysis of the reaction with the substrate D. Key: Most enzymes react with only one reactant, so when a poison blocks the acti ve site, the enzyme can no longer bond with the substrate, causing the chemical reacti on to stop. Friday 11/9/12 The graph shows how the activity of an enzyme changes at different temperatures. Which statement best describes what happens to the enzyme when the temperature of the reaction increases to 63°C? A. The enzyme is used up and the reaction stops. B. The enzyme begins to decrease the rate of the reaction. C. The enzyme continues to increase the rate of the reaction. D. The enzyme changes shape and can no longer speed up the reaction. D. Key: Enzymes have an opti mal temperature range at which they functi on; when the temperature exceeds that range, the enzyme will denature, causing it to change its shape and no longer be able to bind with the substrate. Monday 11/12/12 • • • A scientist formed Chemical X in a laboratory. The material was then analyzed by other scientists. Molecular Structure • • • • • • • • • • • • • Analysis showed that the chemical was composed of long chains of repeated copies of CH2 molecules. 104831 A.4.1.1 9. A researcher noticed that a similar CH2 molecular structure was also located in the plasma membrane of an animal cell. This CH2 molecular structure contained a negatively charged phosphate group. Which statement best describes the primary function of the CH2 and phosphate molecular structure located in the plasma membrane? A. It contains the genetic information needed for protein production. B. It catalyzes specifi c chemical reactions in the cytoplasm of a cell. C. It stores the energy that a cell needs to perform various life processes. D. It allows a cell to regulate the movement of materials into and out of a cell. Tuesday 11/13/12 • Which type of organic molecule was most likely formed by the scientist in the laboratory? • A. lipid • B. protein • C. nucleic acid • D. carbohydrate Wednesday 11/14/12 • Proteins are a major part of every living cell and have many different functions within each cell. Describe the general composition of a protein molecule. Thursday 11/15/12 • Carbohydrates also perform numerous roles in living things. • Describe how the structures of proteins differ from the structures of carbohydrates. Friday 11/16/12 Describe how the functions of proteins differ from the functions of carbohydrates. Monday 11/ 19 • Students’ Observations of a Pond Ecosystem Quantitative Qualitative 37 fish and 3 frogs Leaves lie on the bottom of the pond. 2 types of aquatic grass Water insects move along the water’s surface. 12 small rocks and 1 medium rock All 3 frogs are sitting on a pond bank. A group of students measured a ten-square-meter section of a pond ecosystem and recorded observations. Which statement is a testable hypothesis? • A. The frogs living in the pond represent a population. • B. Water is an abiotic component in the pond ecosystem. • C. If the fish are given more food, then they will be happier. • D. If the frogs are startled, then they will jump into the water. 11/20/12 Tuesday • Why might growth slow from an exponential rate in a population of sheep? • (A) Disease • (B) Lack of space • (C) Wolves • (D) All of the above • (E) None of the above 11/21/12 Wednesday • What is a relationship in which two organisms both benefit from their association? • (A) Symbiosis • (B) Mutualism • (C) Commensalism • (D) Parasitism • (E) Competition 11/27/12 Tuesday Why is energy lost as it moves from producers to primary consumers? • (A) Saprophytic activity • (B) Biomass decreases • (C) Secondary consumers eat primary consumers • (D) Respiration and metabolic activity • (E) None of the above 11/ 28/ 12 Wednesday • Which of the following organisms participate in the nitrogen cycle? • (A) Denitrifying bacteria • (B) Chemosynthetic bacteria • (C) Saprophytes • (D) All of the above • (E) None of the above Thursday 11/29/12 • Which of the following releases carbon dioxide into the atmosphere? • (A) Animal consumption of producers • (B) Photosynthesis • (C) Chemosynthesis • (D) Bacterial decay • (E) None of the above Monday 12/3 • A species of snapping turtles has a tongue that resembles a worm. The tongue is used to attract small fish. Which best describes the interaction between the fish and the snapping turtle? • A. predation • B. symbiosis • C. parasitism • D. competition 12/4/12 Tuesday • In a plains community, the population with greatest biomass would be • (A) hawks • (B) foxes • (C) prairie dogs • (D) grasses • (E) beetles 12/5 Wednesday • Which sequence correctly describes the flow of energy between organisms in a marine food web? seal • penguin sea bird • small fish whale • • krill • A. from seals to penguins to krill • B. from whales to krill to small fish • C. from sea birds to seals to penguins • D. from small fish to penguins to seals 12/6 Thursday • Which statement correctly describes how nitrogen in the soil returns to the atmosphere? • A. soil bacteria convert nitrates into nitrogen gas • B. Decomposers directly convert ammonium into nitrogen gas • C. Plants assimilate nitrites & convert them into nitrogen gas • D. Nitrogen fixing bacteria in plant roots convert nitrates into nitrogen gas. 12/7 Friday • Agricultural runoff can carry fertilizers into lakes & streams. This runoff can cause algae populations to increase. Which effect does this change in the algae population sizes most likely have on affected lakes & streams? • A. increase in water level • B. increase in water clarity • C. reduction in dissolved oxygen needed by fish • D. reduction in temperature variations near the water’s surface Monday 12/10 • If the flow of energy in an Arctic ecosystem goes through a simple food chain from seaweeds to fish to seals to polar bears, then which of the following is TRUE? A. Polar bears can provide more food for Eskimos than seals can. B. The total energy content of the seaweeds is l lower than that of the seals. C. Polar bear meat probably contains the highest concentrations of fat-soluble toxins. D. Seals are more numerous than fish. E. The carnivores can provide more food for the Eskimos than the herbivores can. Tuesday 12/11 • All of the following are likely results of landclearing operations such as deforestation and agricultural activity EXCEPT: A. Destruction of plant and animal habitats. B. Erosion of soil due to increased water runoff. C.Leaching of minerals from the soil. D.Rapid eutrophication of streams and lakes. E.Decreased carbon dioxide in the atmosphere. 12/12 Wednesday • Human use of prokaryotic organisms to help detoxify a polluted wetland would be an example of: A. Ecosystem augmentation. B. Keystone species introduction. C. Biological control. D. Bioremediation. E. Population viability analysis. 12/13 Thursday • The diagram below represents a food web for a particular terrestrial ecosystem. Each letter is a species. The arrows represent energy flow. Answer the following questions concerning this figure. • Which species is the producer? 12/14 Friday The diagram below represents a food web for a particular terrestrial ecosystem. Each letter is a species. The arrows represent energy flow. Answer the following questions concerning this figure. Which species is most likely the decomposer? 12/17 Monday The diagram below represents a food web for a particular terrestrial ecosystem. Each letter is a species. The arrows represent energy flow. Answer the following questions concerning this figure. A toxic pollutant would probably reach its highest concentration in which species? 12/18 Tuesday The diagram below represents a food web for a particular terrestrial ecosystem. Each letter is a species. The arrows represent energy flow. Answer the following questions concerning this figure. Excluding the decomposer, biomass would probably be smallest for which species? 12/19 Wednesday • A typical pyramid of energy has a broad base tapering to a narrow top. The primary reason for this pattern is that: A. Secondary consumers require less energy than producers. B. At each step, energy is lost from the system as a result of keeping the organisms alive. C. As materials pass through ecosystems, some of them are lost to the environment. D. Biomagnification of toxic materials limits the secondary and tertiary consumers. E. Secondary consumers have a more general diet than primary producers. 12/20 Thursday Which of the following statements about the ozone layer are true: A. The ozone layer has been eroded by the release of chloroflourocarbons. B. The ozone layer is thinnest at the equator. C. Ozone caused by automobile emissions is slowly replacing lost ozone at higher atmospheres. D. The release of pollutants from manufacturing sources had destroyed the ozone layer directly over major industrial centers. E. Deforestation and "slash and burn" land clearing are responsible for most of the ozone layer depletion seen today. 1/2 Wednesday • Differentiate between a food chain and a food web. Which is more likely to exist in nature? 1/3 Thursday • Which characteristic is shared by all prokaryotes & eukaryotes? • • • • A. ability to store hereditary info B. use of organelles to control cell processes C. use of cellular respiration for energy release D. ability to move in response to environmental stimuli 1/4 Friday • Which statement best describes an effect of the low density of frozen water in a lake? • A. When water freezes, it contracts, decreasing the water level in a lake. • B. Water in a lake freezes from the bottom up, killing most aquatic animals. • C. When water in a lake freezes, it floats, providing insulation for organisms below. • D. Water removes thermal energy from the land around a lake, causing the lake to freeze. 1/7 Monday • Which statement best describes a difference between prokaryotic cells and eukaryotic cells? • A. The presence of both DNA and ribosomes in prokaryotic cells indicates that they are more complex than eukaryotic cells. • B. The larger size of prokaryotic cells indicates that they are more complex than eukaryotic cells. • C. The presence of membrane-bound organelles in eukaryotic cells indicates that they are more complex than prokaryotic cells. • D. The larger size of eukaryotic cells indicates that they are more complex than prokaryotic cells. 1/8 Tuesday • Which component of this membrane contains a hydrophobic region and acts as the primary barrier to most foreign substances? • A. protein • B. cholesterol • C. carbohydrate chain • D. phospholipid bilayer 1/9 Wednesday • Scientists observed that the populations of toplevel consumers in a particular ecosystem were rapidly decreasing. Further studies revealed that there was also a decline in producer productivity. Which other changes did the scientists most likely observe in the ecosystem? • A. increased producer diversity • B. decreased population size at all levels • C. decreased primary consumer populations only • D. increased primary and secondary consumer diversity 1/10 Thursday • The structure found in ALL cells that encloses a cell from the outside is the ______. • • • • A. Cytosol B. Cell wall C. Endoplasmic Reticulum D. Cell membrane 1/11 Friday • Due to having less items in the cell, and less complex, ________ are usually smaller • • • • A. Prokaryotes B. Eukaryotes C. Both D. Neither 1/14 Monday • The function of the nucleus is to: • • • • A. make the cell bigger B. make proteins C. surround and protect the cell D. surround and protect DNA 1/15 Tuesday • Which of the following correctly matches a cell part with its function? • • • • A. mitochondria...photosynthesis B. nucleus...make ATP C. vesicle/vacuole...storage D. lysosome...movement 1/16 Wednesday • This cell barrier refers to the "fluid mosaic mode" and is highly selective about what passes through • A. gap junction • B. cell wall • C. nuclear membrane • D. cell membrane 1/17 Thursday • The diffusion of water across a membrane is known as: • • • • A. facilitated diffusion B. active transport C. osmosis D. diffusion 1/18 Friday Living organisms can be classified as prokaryotes or eukaryotes. Which two structures are common to both prokaryotic and eukaryotic cells? A. Cell wall and nucleus B. Cell wall and chloroplast C. plasma membrane and nucleus D. plasma membrane and cytoplasm 1/22 Tuesday 1/23 Wednesday 1/24 Thursday 1/25 Friday • Which statement best compares the energy transformations of photosynthesis and cellular respiration? • A. Only photosynthesis uses oxygen to create energy. • B. Only photosynthesis causes an increase in kinetic energy. • C. Photosynthesis and cellular respiration both store energy in chemical bonds. * • D. Photosynthesis and cellular respiration both require chemical energy to make food. Tail length in mice varies within a population. Scientists observed change in the distribution of tail lengths in a mouse population over time. At the genetic level, what has most likely happened to the allele for the shortest tail lengths? A. The allele changed from being dominant to being recessive. B. The allele changed from being autosomal to being sex-linked. C. The allele became less frequent than the alleles for longer tail lengths. D. The allele began to code for long tail lengths instead of the shortest ones. Thursday 11/ 29