2019 ap bio frq

3 min read 10-12-2024

Conquering the 2019 AP Biology Free Response Questions (FRQs)

The 2019 AP Biology exam presented students with a challenging set of free-response questions (FRQs). This article will dissect those questions, providing insights into successful approaches and highlighting key concepts tested. Mastering these questions requires a strong understanding of fundamental biological principles and the ability to apply them to novel scenarios. Let's dive into the 2019 AP Biology FRQs.

Question 1: Enzyme Activity and Environmental Factors

This question explored the impact of environmental factors on enzyme activity. Students were presented with data on enzyme activity at various temperatures and pH levels. Understanding the concept of optimal conditions for enzyme function was crucial.

Key Concepts Tested: Enzyme structure and function, the relationship between enzyme activity and temperature/pH, denaturation, and interpreting graphical data.
Successful Approach: Students needed to accurately interpret the provided graphs. They needed to explain how temperature and pH affect enzyme structure and, consequently, catalytic activity. Explaining the concept of denaturation at extreme temperatures or pH values was essential for a high score.
Example Response Structure:
- (a) Describe the relationship between enzyme activity and temperature shown in the graph.
- (b) Explain the effect of pH on enzyme activity. Include a discussion of the optimal pH.
- (c) Predict the enzyme activity at a temperature/pH outside the range provided, justifying your prediction.

Question 2: Cellular Respiration and Photosynthesis

This FRQ focused on the interconnectedness of cellular respiration and photosynthesis. Students were asked to analyze processes and energy transfers within these metabolic pathways.

Key Concepts Tested: Photosynthesis (light-dependent and light-independent reactions), cellular respiration (glycolysis, Krebs cycle, electron transport chain), ATP production, and the role of electron carriers (NADH, FADH2).
Successful Approach: A clear understanding of the inputs and outputs of each process was vital. Students needed to trace the flow of energy and the role of key molecules in both photosynthesis and cellular respiration. Connecting the two processes – the products of one being the reactants of the other – was critical.
Example Response Structure:
- (a) Describe the overall process of photosynthesis.
- (b) Explain how cellular respiration uses the products of photosynthesis.
- (c) Compare and contrast ATP production in photosynthesis and cellular respiration.

Question 3: Population Genetics and Evolution

This question delved into population genetics and evolutionary principles. Students were presented with a scenario involving allele frequencies in a population and were asked to analyze changes over time.

Key Concepts Tested: Hardy-Weinberg equilibrium, allele and genotype frequencies, natural selection, genetic drift, and the conditions necessary for Hardy-Weinberg equilibrium.
Successful Approach: Applying the Hardy-Weinberg equation was crucial. Students needed to identify factors that could disrupt equilibrium and explain how these factors could lead to changes in allele frequencies. A strong grasp of the five conditions for Hardy-Weinberg equilibrium was necessary.
Example Response Structure:
- (a) Calculate allele and genotype frequencies using the Hardy-Weinberg equation.
- (b) Explain how a specific factor (e.g., natural selection, genetic drift) could alter allele frequencies.
- (c) Predict the long-term effect of this factor on the population's genetic diversity.

Question 4: Plant Responses and Environmental Stimuli

This FRQ examined plant responses to environmental stimuli, focusing on tropisms.

Key Concepts Tested: Phototropism, gravitropism, auxin, and the role of plant hormones in mediating responses to environmental cues.
Successful Approach: Students had to demonstrate understanding of the mechanisms underlying plant tropisms. Explaining the role of auxin in mediating these responses was a key element. Relating the responses to adaptive advantages for the plant was also important.
Example Response Structure:
- (a) Define phototropism and gravitropism.
- (b) Explain the role of auxin in mediating these responses.
- (c) Discuss the adaptive significance of these tropisms for plant survival.

Question 5: Animal Behavior and Communication

This question explored animal behavior, particularly communication methods.

Key Concepts Tested: Types of animal communication (visual, auditory, chemical, tactile), the function of communication in various contexts (mating, predator avoidance, etc.), and the evolutionary significance of communication.
Successful Approach: Students needed to provide specific examples of animal communication methods and explain how they contribute to the animal's survival and reproduction. Discussing the evolutionary pressures shaping communication strategies was crucial.
Example Response Structure:
- (a) Describe different types of animal communication.
- (b) Explain how a specific communication method helps an animal survive or reproduce.
- (c) Discuss the evolutionary basis of this communication method.

By understanding the key concepts and approaches outlined above, you can better prepare for future AP Biology FRQs. Remember to practice with past exams and seek feedback on your responses to refine your skills. Good luck!