Chloroplast Structure
This lesson covers:
- The function of chloroplasts
- The structure of chloroplasts
The function of chloroplasts
Chloroplasts are the site of photosynthesis. They are organelles found in some algae and plant cells. In plants, they are mainly found in the mesophyll tissues of leaves.
The main roles of chloroplasts are:
- To absorb light energy to drive photosynthesis.
- To convert light energy into chemical energy.
The structure of chloroplasts
Chloroplasts are surrounded by a double membrane.
The interior of chloroplasts contains:
- Thylakoids - These flattened sacs contain complexes of pigments like chlorophyll in their membranes to absorb light for the light-dependent reaction.
- Grana - These are stacks of thylakoids.
- Lamellae - These are membranous extensions that connect thylakoids.
- Stroma - This is a fluid surrounding the thylakoids where the light-independent reaction occurs.
- Starch grains - These store sugars.
- Ribosomes - These are for protein synthesis within the chloroplast.
- Chloroplast DNA - This has genes that code for proteins involved in photosynthesis.