AP Biology Exam FRQ's 2023 with 100% correct answers

(Unit 1) Describe the role of carbon in biological systems. correct answersCarbon is used to build biological macromolecules such as carbohydrates, proteins, nucleic acids, and lipids. (Unit 1) Explain how, when the membranes are fused, the polar parts of the phospholipids from one cell will interact with the phospholipids from the other cell and how the nonpolar parts of the phospholipids from one cell will interact with the phospholipids from the other cell. correct answersWhen the membranes are fused, the polar parts of the phospholipids (hydrophilic head) from one cell to the other dissolves in water and forming hydrogen bonds with the water. The non polar parts of the phospholipids (hydrophobic tail) from one cell to the other avoids water. They create a lipid bilayer where the hydrophobic tails are between the hydrophilic heads. When this layer is formed the heads are exposed to water while the tails only interact with other tails not the water. (Unit 1) Make a claim about the most immediate effect on the fused B-cancer cells if the fused cells are transferred to a growth medium that lacks a source of nitrogen. correct answersThe denature of the B-cancer cells would be the most immediate effect if the fused cells are transferred to a growth medium that lacks a source of nitrogen. The cells will either die OR be unable to synthesize DNA and RNA/nucleic acids/nucleotides and amino. (Unit 1) Provide reasoning with evidence based on the composition of biological macromolecules to support your claim. correct answersNitrogen is a part of the base component in the biological macromolecules (nucleic acids (DNA, RNA, or nucleotides) and amino acids (polypeptides, or proteins)) meaning that if there is a lack of it the B-cancer cells would not be able to properly function or exist due to it missing and important component to its structure. Identify the process used to form the covalent peptide bonds that join amino acids into a polypeptide. correct answers2 amino acids were joined together into a polypeptide by hydrolysis, which is in its most basic description, the loss of a hydrogen molecule. The change in the amino acid sequence illustrated in Figure 1 caused a change in the shape of Receptor X. Based on the R groups of the original and substituted amino acids, explain why Receptor X changed shape. correct answersBased on the R groups of the original and substituted amino acids, two amino acids with charged or ionic or hydrophilic R-groups were replaced by two amino acids with uncharged or nonpolar or hydrophobic R-groups.