AP Biology :2.4 Membrane Permeability - Exam Style questions with Answer- FRQ
Question
TOPIC – 2.4 Membrane Permeability
(a) – TOPIC – 2.4 Membrane Permeability
(b) – TOPIC – 2.4 Membrane Permeability
(c) – TOPIC – 2.4 Membrane Permeability
Cystic fibrosis is a genetic condition that is associated with defects in the CFTR protein. The CFTR protein is a gated ion channel that requires ATP binding in order to allow chloride ions (Cl−) to diffuse across the membrane.
(a) In the provided model of a cell, draw arrows to describe the pathway for production of a normal CFTR protein from gene expression to final cellular location.
(b) Identify the most likely cellular location of the ribosomes that synthesize CFTR protein.
(c) Identify the most likely cellular location of a mutant CFTR protein that has an amino acid substitution in the ATP-binding site.
Answer/Explanation
Ans:
(a) In the provided model of a cell, draw arrows to describe the pathway for production of a normal CFTR protein from gene expression to final cellular location.
Drawing (1 point)
The response must follow this pathway: nucleus/nuclear envelope \(\rightarrow \) endoplasmic reticulum \(\rightarrow \) Golgi apparatus \(\rightarrow \) plasma membrane.
The response may be in the form of a continuous arrow or multiple discontinuous arrows.
(b) Identify the most likely cellular location of the ribosomes that synthesize CFTR protein.
Identification (1 point)
• (Rough) Endoplasmic Reticulum/ER
(c) Identify the most likely cellular location of a mutant CFTR protein that has an amino acid substitution in the ATP-binding site.
Identification (1 point)
• In the (cellular/plasma) membrane
(b) The ribosomes that synthesize the CETR protein would probably be found on the rough ER.
(c) The mutant CFTR protein is likely embeded in the plasma membrane.