Question

which two of the following are features of abc transporters? composed entirely of lipids transport dna into the cell act as carriers in facilitated diffusion contain a cytoplasmic domain that binds atp span the plasma membrane

Explanation:

1. Analyze each option:

• "composed entirely of lipids": ABC transporters are proteins, not lipids, so this is incorrect.
• "transport DNA into the cell": ABC transporters are mainly for transporting molecules like nutrients, drugs, etc., not DNA (DNA uptake in prokaryotes is via other mechanisms), so this is incorrect.
• "act as carriers in facilitated diffusion": ABC transporters are active transporters (use ATP), not for facilitated diffusion (which is passive), so this is incorrect.
• "contain a cytoplasmic domain that binds ATP": ABC (ATP - Binding Cassette) transporters have a cytoplasmic domain that binds and hydrolyzes ATP to drive transport, so this is correct.
• "span the plasma membrane": ABC transporters are integral membrane proteins, so they span the plasma membrane, this is correct.

Answer:

D. contain a cytoplasmic domain that binds ATP, E. span the plasma membrane