Select ALL the components of a photosystem. stomata and guard cell Lipids a reaction center chlorophyll accessory pigments chlorophyll pigment
The Correct Answer and Explanation is:
Correct Answer:
- ✅ a reaction center chlorophyll
- ✅ accessory pigments
- ✅ chlorophyll pigment
Explanation:
A photosystem is a complex found in the thylakoid membranes of chloroplasts, and its main role is to capture light energy and convert it into chemical energy during photosynthesis. There are two major types of photosystems: Photosystem I (PSI) and Photosystem II (PSII). Despite their differences, both share several essential structural components.
- Reaction center chlorophyll: This is the core of the photosystem. In Photosystem I, the reaction center contains a special chlorophyll molecule called P700, while in Photosystem II, it contains P680. These chlorophyll molecules are responsible for converting the energy of absorbed light into chemical energy by donating electrons to the electron transport chain.
- Chlorophyll pigment: This refers to all chlorophyll molecules involved in the photosystem. These include both the reaction center chlorophyll and the light-harvesting complex chlorophylls that collect light energy and transfer it to the reaction center.
- Accessory pigments: These are pigments such as carotenoids and phycobilins that absorb light wavelengths not efficiently captured by chlorophyll. They pass the energy to chlorophyll to improve the efficiency of light absorption. They protect the plant by dissipating excess energy and expanding the range of usable light.
Incorrect choices:
- Stomata and guard cells are part of the leaf structure and control gas exchange, not part of the photosystem itself.
- Lipids are components of membranes in which the photosystems are embedded, but they are not structural components of the photosystems.
Therefore, the components that are part of a photosystem are:
a reaction center chlorophyll, accessory pigments, and chlorophyll pigment.
