3b additional practice: classify transport as facilitated diffusion or active transport\n\nthe figure shows…

3b additional practice: classify transport as facilitated diffusion or active transport\n\nthe figure shows a cell membrane with two transport proteins (proteins 1 and 2) and three molecules (molecules 1, 2, and 3). the membrane permeability of each molecule is shown to the right.\n\nwhich type of molecule moves through the membrane by facilitated diffusion involving a carrier protein?\n\na. molecule 1\nb. molecule 2\nc. molecule 3\nd. none of the molecules moves through a carrier protein.\ne. i do not know the answer.

3b additional practice: classify transport as facilitated diffusion or active transport\n\nthe figure shows a cell membrane with two transport proteins (proteins 1 and 2) and three molecules (molecules 1, 2, and 3). the membrane permeability of each molecule is shown to the right.\n\nwhich type of molecule moves through the membrane by facilitated diffusion involving a carrier protein?\n\na. molecule 1\nb. molecule 2\nc. molecule 3\nd. none of the molecules moves through a carrier protein.\ne. i do not know the answer.

Answer

Explanation:

Step1: Identify transport mechanism for Molecule 1

Molecule 1 (purple circles) moves through Protein 1 from high to low concentration without ATP. Protein 1 is a channel protein, not a carrier.

Step2: Identify transport mechanism for Molecule 2

Molecule 2 (pink triangles) moves through Protein 2 against its concentration gradient (low to high) using ATP. This is active transport.

Step3: Identify transport mechanism for Molecule 3

Molecule 3 (green squares) moves through Protein 2 from high to low concentration without ATP. Protein 2 changes shape to move it, acting as a carrier protein.

Step4: Determine the correct molecule

Facilitated diffusion involves moving down a gradient via a protein. Molecule 3 uses Protein 2, which functions as a carrier protein for this passive movement.

Answer:

c. Molecule 3