AP Bio FRQs Latest Version 2024/2025 Graded A+

AP Bio FRQs Latest Version 2024/2025 Graded A+ Based on the model, explain whether the molecules shown crossing the membrane require energy to do so. The response indicates that energy is not required for the substances to cross the membrane because the substances are being passively transported from a region of higher concentration to a region of lower concentration. Depending on the organism, the optimal pH for enolase to catalyze its reaction is between 6.5 and 8.0. Describe how a pH below or above this range is likely to affect enolase and its catalytic ability. The response indicates that a pH below or above this range will most likely cause enolase to denature/change its shape and be less efficient or unable to catalyze the reaction. Describe the biological need for cells to be surrounded by a membrane that is selectively permeable for different materials. The response indicates that a cell membrane separates the internal environment of the cell from the external environment OR that a cell membrane that is selectively permeable can help to regulate what molecules move between the differing environments inside and outside of a cell. Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipid molecules to pass directly across the membrane. The response indicates that the interior of a phospholipid bilayer is hydrophobic, which allows small hydrophobic molecules to diffuse across the membrane. Describe the levels of organization among living things. Organelles, cells, tissues, organs, organ systems, organisms, populations, communities, ecosystems, the biosphere. Describe the relationship between the concentration of glucose in the culture medium and the ATP concentration in the cells. The response indicates that the concentration of glucose appears to have little or no effect on the ATP concentration of the cells. Describe the role of carbon in biological systems. The response indicates that carbon is used to build biological macromolecules such as carbohydrates, proteins, nucleic acids, and lipids. Describe the role of oxygen in cellular respiration. The response indicates that oxygen is the terminal acceptor of electrons that have passed through the electron transport chain. Determine the external concentration of substance L that will result in one-half of the maximal entry rate. The response indicates that the external concentration of substance L that will result in one-half of the maximal entry rate is a value other than one between 31 mM and 34 mM. Explain how the amino acid substitution shown in Figure 1 is most likely to affect the function of Receptor X. The response indicates that because function is determined by shape, the function of receptor X is likely to change OR that the structural change might alter the binding of the molecule to receptor X OR that the structural change might alter the ability of receptor X to cause a cellular response.