EUKARYOTIC CELLS 4 - PLANT ORGANELLES Flashcards
What is the tonoplast?
Specialised membrane that surrounds the permanent vacuole in plant cells & controls movements of substances into/out of the cell sap.
What is the cell sap?
Aqueous solution that fills the permanent vacuole.
What is osmosis?
Specialised form of diffusion, movement of solvent molecules down a concentration gradient through a partially permeable membrane.
What is a chloroplast?
Organelle adapted to carry out photosynthesis, containing the green pigment chlorophyll.
What is chlorophyll?
Green pigment responsible for trapping energy from light, making it available for the plant to use in photosynthesis.
What are amyloplasts ?
Plant organelles that store starch.
What organelles are found in plant cells that aren’t found in animal cells?
Permanent vacuole and chloroplasts.
What is a vacuole?
Any fluid-filled space inside the cytoplasm surrounded by a membrane
How are vacuole is animal cells different to those formed in plant cells?
They are temporary in animal cells, being formed when needed then destroyed.
How does the cell sap affect water in the cell?
It causes water to move in by osmosis, and as a result the cytoplasm is kept against the cell wall, keeping the cells turgid (swollen) and the whole plant upright.
What else do vacuole store?
- Store pigments: e.g. beetroot, if the tissue is heated, characteristics around the vacuole will change and pigment will leak out more rapidly.
- Store proteins.
- Often store waster products and other chemicals
What plants contain chloroplasts?
Only those cells from green parts of plants. However, almost all plants contain genetic information to make chloroplasts.
What are the similarities between chloroplasts?
- Contain their own DNA.
- Are large organelles.
- Surrounded by outer membrane.
- Have folded inner membrane, increases surface area.
- Thought to have been free-living prokaryotic organisms that were engulfed & became part of other cells.
What is different about chloroplasts compared to mitochondria?
- Site of photosynthesis.
- Contain chlorophyll, green pigment, for trapping light energy.
- Formed from relatively unspecialised plant organelle known as leucoplast.
Describe how amyloplasts are used in plants?
Developed from leucoplasts; colourless; store starch; can be converted into glucose & used to provide energy.
