Pigment molecules absorb light energy.
A substrate fits into the active site of an enzyme like a lock and key. The substrate has a certain shape that matches or is very similar to the shape of the enzyme so it's the perfect fit, like "a lock and key."
Answer: envelope membranes
Like mitochondria, chloroplasts are surrounded by 2 membranes. The outer membrane is permeable to small organic molecules, whereas the inner membrane is less permeable and studded with transport proteins.
An electron is symbolized by a minus (-) sign.
Please mark brainliest if it is correct. :)