Practice Test 67 - High School Biology

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

Use the simplified nitrogen cycle diagram description below. Boxes: - Atmosphere (N $_2$ ) - Soil: NH $_4^+$ (ammonium) - Soil: NO $_3^-$ (nitrate) - Plants - Animals - Decomposers Arrows (process labels): - Atmosphere (N $_2$ ) → Soil: NH $_4^+$ (nitrogen fixation by bacteria) - Soil: NH $_4^+$ → Soil: NO $_3^-$ (nitrification) - Soil: NO $_3^-$ → Plants (plant uptake) - Plants → Animals (consumption) - Plants/Animals → Decomposers (death & waste) - Decomposers → Soil: NH $_4^+$ (decomposition/ammonification) - Soil: NO $_3^-$ → Atmosphere (N $_2$ ) (denitrification) Which arrow represents the process that returns nitrogen to the atmosphere?
Atom accounting: A plant has 60 carbon atoms available in glucose molecules it produced earlier. During growth, the plant builds macromolecules so that 30 carbon atoms end up in starch, 20 carbon atoms end up in lipids, and 10 carbon atoms end up in proteins (with nitrogen added from soil). Which statement is most accurate?
In a plant, root hair cells absorb water. Many root hair cells together form a root tissue, and multiple tissues form a root. The root is part of the root system. What level of organization is the root?
When a person becomes dehydrated, the body must conserve water. How do the circulatory and excretory systems interact to help regulate water balance?
Two students propose different models for the relationship between photosynthesis and cellular respiration. Student X: "Energy and matter both cycle in a loop: Sun → photosynthesis → respiration → Sun." Student Y: "Matter cycles between photosynthesis and respiration, but energy flows from the Sun and eventually leaves as heat." Which statement is most accurate?
What role does ATP play in cells that are actively carrying out tasks such as active transport, protein synthesis, or muscle contraction?
A forest energy pyramid follows the 10% rule. Producers have 80,000 kcal. About how much energy is available to tertiary consumers (three transfers: producers → primary → secondary → tertiary)?
In a pond, algae photosynthesize during the day and both algae and fish perform cellular respiration day and night. You want a single diagram that shows (1) how matter (CO2, H2O, O2, glucose) cycles between photosynthesis and respiration and (2) how energy flows from the Sun through the system. Which diagram would be the best choice?
Claim: A fish population in Lake M evolved smaller body size due to heavy fishing that removes large fish. Evidence to evaluate: 1) Average adult body length was 32 cm in 1980 and 24 cm in 2020. 2) In a common-garden experiment, offspring of 2020 fish raised with the same food and temperature as 1980 fish still grew to a smaller average size. 3) A fisherman reported catching one unusually small fish in 1980. 4) The lake's water temperature increased by 2°C from 1980 to 2020. Which choice best evaluates whether the evidence supports the claim that the population evolved smaller size (not just responded to the environment)?
A student drinks a large bottle of water after practice and later urinates more than usual. Which model best shows how the digestive, circulatory, and excretory systems interact in this situation?
In a snail population, shell thickness is controlled by alleles $T$ and $t$ . A new crab predator can crush thin shells more easily. Survival probabilities are: thick-shell phenotype = 85% survive, thin-shell phenotype = 25% survive. Which prediction best matches natural selection over several generations?
A student says, "All mutations change proteins in the same way." Which statement most accurately corrects this idea using mutation types?
A forest bird is declining because its nesting habitat is being converted to housing. A conservation group proposes planting 5,000 nest boxes in remaining small forest patches, while development continues. Another proposal is to protect a large, connected forest tract from development using a conservation easement. Which proposal is more likely to be effective and sustainable for the bird population, and why?
A growing plant cell must produce large amounts of cellulose. Why is synthesizing cellulose important for the cell's function?
A classroom has two identical sealed bottles. Bottle 1 is kept in constant light. Bottle 2 is kept in complete darkness. Each bottle contains a small aquatic plant and a few small animals. Which model best explains why Bottle 1 can continue longer than Bottle 2, using both matter cycling (CO2, H2O, O2, glucose) and energy flow?
After eating a meal, a person's blood glucose rises from about 90 mg/dL to 135 mg/dL. Cells in the pancreas detect the rise and release insulin, which causes body cells to take up glucose and the liver to store glucose. Two hours later, blood glucose is back near 95 mg/dL and insulin release decreases. What would most likely happen if the insulin response did NOT occur after the meal?
A population of insects has two genotypes for a gene affecting pesticide resistance: $RR$ and $rr$ (assume heterozygotes are not present for simplicity). In Field A, $RR$ insects have a 90% chance of surviving spraying and $rr$ insects have a 10% chance. In Field B, $RR$ insects have a 90% chance and $rr$ insects have an 85% chance. In which field will the resistance trait increase more quickly, and why?
A region wants to reduce bird deaths caused by collisions with tall buildings during migration. Two actions are proposed: Action A: Require new buildings to use bird-safe glass and reduce nighttime lighting during peak migration weeks. Action B: Collect dead birds each morning and dispose of them to keep sidewalks clean. Which action is more effective at reducing the negative human impact on the ecosystem, and why?
Emperor penguins in Antarctica often huddle in large groups during winter storms. What is the best explanation for why huddling is advantageous compared with standing alone?
A structure is described as: "A group of many similar elongated cells that contract together to produce movement." At what level of biological organization is this structure?

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