Thylakoid Membranes

Definition

These are internal membranes of a chloroplast where light-dependent reactions occur during photosynthesis. They contain pigments such as chlorophyll which absorb light energy.

Analogy

Thylakoid membranes are like sponges soaking up sunlight. Just as sponges absorb water, these membranes absorb light for use in photosynthesis.

Related terms

Photosystem II & I: These are protein complexes involved in photosynthesis that participate in the primary photochemistry of photosynthesis - they capture photons and transfer electrons. They're like specific spots on our sponge that do most of absorbing work.

Lumen: The interior space enclosed by thylakoid membrane; this is where protons accumulate during light-dependent reactions - think about it as absorbed water in our sponge analogy.

Cytochrome complex: A group of proteins that act as an electron carrier during photosynthesis, like a bucket brigade passing the electrons along.