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Practice Test 40 - High School Biology

20 questions. Answer them in any order, then submit to see your score and every explanation.

  1. Claim: Plants remove carbon from the atmosphere during photosynthesis, supporting carbon cycling. Evidence: 1) In a classroom, CO2_2 near a sunlit plant drops by 40 ppm over 30 minutes. 2) In the same classroom corner with no plant, CO2_2 stays about the same. 3) The plant's mass increases over several weeks when given light and water. 4) The plant has a strong smell. Which evidence is best for supporting the specific claim about removing carbon from the atmosphere?
  2. A diagram uses arrows to show energy flow: [Sun] → [Leaf chlorophyll] → [Glucose] → [Cellular respiration] → [ATP for cell work] Which interpretation is most consistent with the arrow directions?
  3. Which option best matches the correct order of events in a typical homeostatic (negative feedback) loop for an internal condition such as temperature or glucose? 1) A response changes the condition 2) A sensor detects the current condition 3) A control center compares the value to a set point and signals a response​
  4. Which sequence correctly lists the stages from the start of mitosis to the end of cell division (including cytokinesis)?
  5. A river section was contaminated by an oil spill in Year 0. Cleanup removed most oil within 3 months. Scientists tracked river productivity using algae growth on tiles (mg of algae per tile per week). Algae productivity data: - Pre-spill: 18 mg/tile/week - 1 month after spill: 3 mg/tile/week - 6 months after spill: 9 mg/tile/week - Year 2: 16 mg/tile/week Based on these data, approximately how long did it take for productivity to recover to near pre-spill levels?
  6. Translation is part of gene expression: DNA → mRNA → protein. Where does translation occur in a typical eukaryotic cell?
  7. A wildfire burns through a shrubland and kills many mice regardless of where they were living. The fire occurs during a year when the mouse population was both high in some areas and low in others, but the fire killed mice in all areas it reached. Which best classifies the wildfire as a limiting factor?
  8. A trait is considered an adaptation when it increases survival or reproduction in a particular environment and becomes common in a population over many generations. Which statement best describes why adaptations are not the same as an individual organism "adjusting" to its environment?
  9. A student summarizes transcription like this: "DNA stays protected in the nucleus, but the cell needs a copy of a gene's instructions that can travel to where proteins are made." Which statement best describes the purpose of transcription?
  10. A small cut starts bleeding. Chemicals released at the cut activate platelets, and activated platelets release more chemicals that activate even more platelets. The process speeds up until a clot forms and bleeding stops. Which type of feedback is described?
  11. A factory releases mercury into a river. Small aquatic organisms absorb the mercury, small fish eat those organisms, and larger fish eat the small fish. Tests later show the highest mercury levels in the largest predatory fish. Which process best explains this pattern?
  12. Early embryos of fish, chickens, and humans show similar features such as a tail-like structure and pharyngeal arches (structures in the neck region) during early development, even though these features look different in adults. Which type of evidence is this, and what does it support?
  13. A food chain follows the 10% rule. If primary consumers have 4,000 kcal of energy, about how much energy is available to secondary consumers?
  14. A scientist uses three observations to support evolution: (1) fossils in older rock layers differ from fossils in younger layers, showing a sequence of change; (2) the forelimbs of mammals share the same basic bone plan; and (3) closely related species have more similar DNA sequences than distantly related species. Which choice best describes how these observations support evolution?
  15. Claim: Energy flows one-way through ecosystems and does not cycle. Evidence: 1) A meadow receives sunlight each day; when a similar meadow plot is covered so no light enters for 2 weeks, most plants die. 2) Biomass measured in the same meadow: producers 10,000 kg, herbivores 1,200 kg, carnivores 120 kg. 3) A thermometer placed in a compost pile rises from 20°C to 55°C during active decomposition. 4) Nitrogen concentration in soil increases after leaf litter decomposes. Which combination of evidence most directly supports the claim about energy flow (not matter cycling)?
  16. A textbook states: "DNA stores genetic information in the sequence of nucleotide bases." Which statement is the best interpretation of this idea?
  17. A scientist compares two processes: (1) a child growing taller over several years and (2) skin closing after a scrape. Which choice correctly describes what both processes have in common at the cellular level?
  18. In a population of insects, wing length is influenced by alleles LL and ll. A windy environment favors shorter wings. Survival probabilities are: LLLL = 30%, LlLl = 50%, llll = 70%. Which statement best predicts how allele frequencies will shift?
  19. An endangered frog breeds in seasonal ponds but spends most of the year in nearby forest. A conservation plan includes: 1) Protecting a connected corridor of forest between ponds 2) Removing introduced predatory fish from breeding ponds 3) Captive breeding and releasing tadpoles into restored ponds Which evaluation best explains why this plan is more likely to succeed than captive breeding alone?
  20. Why are siblings (from the same two parents) usually genetically different from each other?

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