The ultrastructure of plant cells Flashcards
What extra cell components do plants cells have?
- Cell wall
- Permanent vacuole
- Chloroplast
What are vacuoles?
Membrane lined sacs in the cytoplasm containing cell sap.
Why do plants have permanent vacuoles?
They help to keep the cell turgid, and so that the contents of the cell push against the cell wall and maintain a rigid framework.
What is the membrane of a vacuole called?
Tonoplast
Why is the vacuole selectively permeable?
So that some small molecules can pass through it but others cannot.
What is the major reaction that happens inside the chloroplast?
Photosynthesis
Where are chloroplast found in plant cells?
Inside the green parts, such as the stems and leaves.
Describe the structure of the chloroplast
They have a double membrane with fluid inside called the stroma. They have an interior network of membranes, which form flattened sacs called thylakiods. Several of these thlokiods stacked together are called granum (plural grana). The grana are held together by membranes called lamellae
What do grana contain?
The chlorophyll pigments
What happens inside the chlorophyll pigments?
Light dependent reactions occur during photosynthesis
What is the equation for photosynthesis
carbon dioxide + water —> glucose + oxygen + water
What is the symbol equation for photosynthesis
6CO2 + 6H2O —> C6H12O6 + 6O2
Do chloroplast contain DNA and ribosomes?
Yes (just like the mitochondria)
What are plant cell walls made of?
Cellulose (a carbohydrate)
The fact that chloroplast contain there own DNA and ribosomes allows them to make what?
There own proteins
Why are plant cell walls freely permeable?
To allow substances to pass in and out of the cell through the cellulose wall.
Why do plants have a cell wall?
To maintain there rigid shape. And to protect the contents of the cell against invading pathogens.
What do the plasmodesmata allow for?
One cell to exchange material with another (via the cytoplasm).
Draw and label a plant cell
