What is the growth response shown by the shoot and roots and what is the primary growth pattern of roots and shoot?
The growth response of both shoots and roots in plants is influenced by various environmental factors and internal regulatory mechanisms. These growth responses can be categorized into primary and secondary growth patterns.
Primary Growth:Primary growth is the initial growth in plants that leads to an increase in length of both shoots and roots. It occurs in the apical meristems, which are regions of actively dividing cells located at the tips of stems and roots.
Secondary Growth:Secondary growth, which occurs in some plants, leads to an increase in girth or diameter of stems and roots. This type of growth is particularly prominent in woody plants and is facilitated by lateral meristems such as the vascular cambium and cork cambium.
Growth Responses:The growth response of shoots and roots is influenced by various factors:
In summary, the growth responses of shoots and roots are regulated by various external factors and internal mechanisms, allowing plants to adapt to their environment and optimize their growth patterns. Primary growth, driven by apical meristems, is responsible for the elongation of stems and roots, while secondary growth, facilitated by lateral meristems, leads to an increase in girth in woody plants.
The movement of the plant towards the response of gravity pull is known as geotropism. The roots of the plant show positive stimuli as they grow in the direction of gravity and the stem reflects negative stimuli as it grows in the opposite direction. The shoot of the plant grows towards sunlight and this is called phototropism. The roots grow towards gravity or the earth and this is geotropism. Plant shoots usually grow upward against the pull of gravity. This is an example of negative geotropism, as the plant shoot is growing away from the stimulus, which is the downward force of gravity. The roots, on the other hand, can be seen as positively geotropic as they grow downward toward the pull of gravity. The movement away from a stimulus is called a negative response, and the movement towards the stimulus is a positive response. For example, roots exhibit a positive response to gravity, while stems exhibit a negative response. It is important that plants are anchored in soil to absorb water and nutrients.Both shoots and roots develop from apical meristems, undifferentiated cells clustered at their tips. In roots, a root cap is also produced, which protects the meristem as it grows through the soil the lateral organs of the shoot. The shoot apical meristem produces stems, leaves, and reproductive structures. In phototropism a plant bends or grows directionally in response to light. Shoots usually move towards the light; roots usually move away from it. Shoots are part of a plant that grows above the ground, while roots grow below the ground. The growth of the parts of plants in response to the force of gravity is called geotropism. The upward growth of plant shoots is called negative geotropism. The downward growth of roots is positive geotropism. Phototropism is the ability of the plant to re-orient the shoot growth towards a direction of light source. Phototropism is important to plants as it enhances the ability of plants to optimize their photosynthetic capacity. Primary growth is a result of rapidly-dividing cells in the apical meristems at the shoot tip and root tip. Subsequent cell elongation also contributes to primary growth. The growth of shoots and roots during primary growth enables plants to continuously seek water (roots) or sunlight (shoots). Contrast primary growth in roots and shoots. In roots, primary growth occurs in three successive stages, moving away from the tip of the root: the zones of cell division, elongation, and differentiation. In shoots, it occurs at the tip of apical buds, with leaf primordial arising along the sides of an apical meristem.Gravitropism ensures that roots grow into the soil and that shoots grow toward sunlight. Growth of the shoot apical tip upward is called negative gravitropism, whereas growth of the roots downward is positive gravitropism. The main difference between a shoot and a root is that shoots are parts of the plant that grow above the ground, whereas roots are parts of the plant that grow below the ground
- Badges
- Science topic
- Similar topics
- Mathematics
- Statistics
- Sampling Design
- Sample Size