Plant growth and development
Plant Growth and Development
Active Processes in Growth
- Growth in plants is an active process where cells divide and increase in size.
- This process largely involves two phases: cell division, also known as mitosis, and cell expansion.
- New cells are primarily formed in areas known as meristems found at the tips of roots and shoots.
Processes Driving Development
- Plant development is mainly driven by a variety of different plant hormones, such as auxins, gibberellins, and cytokinins.
- These hormones dictate processes such as phototropism (growth towards light), gravitropism (growth in response to gravity), and dormancy among others.
- Plant development is also co-ordinated through gene expression which guides the correct formation of various plant structures.
Photosynthesis and Growth
- Light absorbed by chlorophyll in the leaves powers photosynthesis, which is central to plant growth.
- During photosynthesis, carbon dioxide, water and light are used to produce glucose (plant food) and oxygen.
- The glucose is then used by the plant to promote synthesis of proteins and nucleic acids necessary for cell division and growth.
Secondary Growth and Development
- Apart from primary development, plants also go through secondary growth which makes them thicker and more resilient.
- This increase in girth is due to the activity of the vascular cambium and cork cambium, which form new xylem, phloem and bark.
- Secondary growth is often seen in woody plants and trees which require more structural support to stand upright.
Environmental Influence on Growth and Development
- Plant growth and development are domains greatly influenced by environmental factors, such as light, water, temperature, and nutrients.
- For instance, inadequate light may limit photosynthesis, thus reducing the plant’s ability to produce nutrients for growth.
- On the other hand, availability of water and essential nutrients in the soil directly influences root development, leaf formation, and overall health.
Effective understanding of plant growth and development involves knowing how complex biological processes work together to form the structure and function of plants. The study of these processes assists in our capacity to cultivate, manage and conserve plant resources.