Question

stroma is: multiple choice a semi - liquid substance surrounding the thylakoid membrane system. a membrane system that contains chlorophyll. an opening in plant leaves that allows gas exchange. the fluid found inside of the thylakoid membranes.

Explanation:

Stroma in chloroplasts is a semi - liquid substance surrounding the thylakoid membrane system where the light - independent reactions of photosynthesis occur. The other options describe different structures: the membrane system with chlorophyll is the thylakoid, the opening for gas exchange in leaves is a stoma, and the fluid inside thylakoid membranes is the thylakoid lumen.

Answer:

a semi - liquid substance surrounding the thylakoid membrane system.