VMBO Year 3 · Organs and cells · Section 1.3
Animal and plant cells
What do animal and plant cells have in common?
A cell can be compared with a tiny factory. It contains cytoplasm, a jelly-like material containing water, dissolved substances and cell structures. Most animal and plant cells have a nucleus, which contains genetic information and controls many cellular processes. A nuclear envelope surrounds the nucleus. The cell membrane encloses the cytoplasm and controls the exchange of substances with the surroundings.
What is different about plant cells?
Plant cells often contain fluid-filled vacuoles. Young cells may have several small vacuoles which merge as the cell grows, usually forming one large central vacuole. A strong cell wall outside the cell membrane provides extra support and protection. It lies outside the living contents of the cell.
Plastids in plant cells
Plant cells may contain several types of plastid, each with a different function.
- Chloroplasts are green and carry out photosynthesis. Their chlorophyll gives green plant parts their colour.
- Chromoplasts contain yellow, orange or red pigments, giving many flowers and fruits their bright colours.
- Starch-storing plastids contain colourless starch grains, storing an important reserve substance.
Plastids can change from one type into another. During the ripening of some fruits, for example, chloroplasts develop into chromoplasts as the fruit changes colour.
Intercellular spaces
Small gaps between plant cells are called intercellular spaces. They contain air or water and help substances move through plant tissues.
Glossary
- Chloroplasts
- Green plastids in which photosynthesis takes place; chlorophyll gives green plant parts their colour.
- Nucleus
- The cell structure containing genetic information and controlling many cellular processes.
- Cell membrane
- A thin boundary around the cytoplasm that regulates the passage of substances.
- Cell wall
- A strong supporting layer outside a plant cell's membrane, surrounding its living contents.
- Cytoplasm
- The jelly-like contents of a cell outside the nucleus, containing water, dissolved substances and cell structures.
- Chromoplasts
- Plastids containing yellow, orange or red pigments which colour many flowers and fruits.
- Vacuoles
- Fluid-filled compartments in plant cells; many mature plant cells have one large central vacuole.
- Starch grains
- Colourless deposits of starch stored as a reserve, often inside specialised plastids.