Vacuoles + Chloroplasts Flashcards
What are vacuoles
Vacuoles are membrane lined sacs in the cytoplasm containing cell sap.
Why are vacuoles important
They are very important in the maintenance of turgor, so that the contents of the cell push against the cell wall and maintain a rigid framework for the cell.
What’s the membrane of the vacuole called
The membrane of a vacuole in a plant cell is called the tonoplast. It is selectively permeable.
Where are chloroplasts found
They are found in the cells in the green parts of plants such as the leaves and the stems but not in the roots
What is a chloroplasts structure
They have a double membrane structure, similar to mitochondria. The fluid enclosed in the chloroplast is called the stroma. They also have an internal network of membranes, which form flattened sacs called thylakoids.
What are several thylakoids stacked together called
Granum (plural grana). The grana are joined by membranes called lamellae. The grana contain the chlorophyll pigments, where light-dependant reactions occur during photosynthesis.
Where is starch present.
Starch produced by photosynthesis is present as starch grains. Like mitochondria, chloroplasts also contain DNA and ribosomes. Chloroplasts are therefore able to make their own proteins.
What do the internal membranes of a chloroplast provide
The internal membranes provide the large surface area needed for enzymes, proteins and pigment molecules necessary in the process of photosynthesis.
