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Living Environment Flashcards

7 cards from real Regents practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

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  1. An antibiotic kills 99% of a bacterial population. The surviving 1% reproduces rapidly. Over time, the population becomes antibiotic-resistant. This is an example of:

    Answer: Natural selection

    Natural selection favors individuals with traits (antibiotic resistance) that improve survival, allowing those traits to increase in the population.

  2. Which statement best describes the role of decomposers in an ecosystem?

    Answer: They recycle nutrients by breaking down dead organic matter

    Decomposers break down dead organisms and waste, returning nutrients to the soil and completing nutrient cycles.

  3. A student wants to test whether temperature affects enzyme activity. Which variable should be kept constant in a controlled experiment?

    Answer: Both pH and amount of enzyme

    In a controlled experiment, all variables except the independent variable (temperature) must remain constant, including pH and enzyme concentration.

  4. The diagram of a food web shows grass → grasshopper → frog → snake → hawk. If the frog population suddenly decreases, which population would most likely decrease next?

    Answer: Snake

    Snakes depend on frogs as a food source, so a decrease in frogs would reduce the food supply for snakes, causing their population to decline.

  5. Which process directly produces gametes in sexually reproducing organisms?

    Answer: Meiosis

    Meiosis is the type of cell division that produces haploid gametes (sperm and egg cells) with half the chromosome number of body cells.

  6. A scientist discovers that two distantly related species have similar bone structures in their front limbs. These structures are called:

    Answer: Homologous structures

    Homologous structures are anatomically similar structures in different species that share a common ancestor, indicating evolutionary relationship.

  7. Insulin is a protein hormone that regulates blood sugar levels. Which organelle is primarily responsible for synthesizing insulin?

    Answer: Ribosome

    Ribosomes are the site of protein synthesis where amino acids are assembled into proteins like insulin based on mRNA instructions.