How do auxin and cytokinin interact to determine size of root apical meristem?
How do auxin and cytokinin interact to determine size of root apical meristem?
In the root meristem, auxin induces the meristematic cell division, whereas cytokinin promotes the cell to switch from the meristematic to differentiated state through inhibiting auxin signaling.
Is cytokinin antagonistic to auxin?
The hormones auxin and cytokinin are essential for plant growth and development. An increase in cytokinin level counteracts this inhibitory effect and leads to an inhibition of auxin signaling. At higher concentrations of both hormones, these antagonistic interactions between cytokinin and auxin are absent.
How does cytokinin affect root growth?
Cytokinin (CK), synthesized in the root cap, promotes cytokinesis, vascular cambium sensitivity, vascular differentiation and root apical dominance. Both IAA and CK regulate root gravitropism.
Does cytokinin inhibit root growth?
Cytokinins Inhibit Lateral Root Development. Cytokinins are known to be involved in multiple developmental processes, including rhizogenesis (Haberer and Kieber, 2002). Kinetin concentrations of 0.1 and 0.5 μM had little effect on primary root length, reducing growth 8.2 and 13.3%, respectively (Figure 1A).
What is auxin antagonistic?
Antagonism between auxin and cytokinin is not the only type of interaction that governs developmental outputs in plants. Rather, synergistic interaction between auxin and cytokinins also exists in processes such as nodule organogenesis [8], light-mediated leaf initiation, and organ positioning [9].
What is the difference between auxin and cytokinin?
Auxin stimulates root branching. > Cytokinin inhibits root branching and lateral root formation….Write the main difference between auxins and cytokinins.
| Auxins | Cytokinins |
|---|---|
| In the stem tip, the auxins are produced. | In the roots, cytokinin is produced and the cytokinins in xylem sap travel upward. |
Which hormone is antagonistic to auxin and why?
We found that auxin at low concentrations limits the action of cytokinin. An increase in cytokinin level counteracts this inhibitory effect and leads to an inhibition of auxin signaling. At higher concentrations of both hormones, these antagonistic interactions between cytokinin and auxin are absent.
Which hormone is antagonistic to gibberellins?
abscisic acid
Dormant seeds germinate when the effects of ABA are suppressed by gibberellins. Due to their opposite effect on plant growth, gibberellins, and abscisic acid can be said to be an antagonist to each other. So, the correct answer is ‘ABA’.
Which hormone is basically telling the plant to slow down and basically to stop producing?
Cytokinins are known to delay senescence in leaf tissues, promote mitosis, and stimulate differentiation of the meristem in shoots and roots. Many effects on plant development are under the influence of cytokinins, either in conjunction with auxin or another hormone.
Does auxin promote root growth?
Introduction. Auxin is considered a key regulator of root growth, gravitropism, and lateral root (LR) formation (Muday and Haworth, 1994). Exogenous auxin treatment has typically resulted in inhibited root growth rate (Zeadan and Macleod, 1984; Hurren et al., 1988; Lloret and Pulgarín, 1992; Gaspar et al., 2003).
Is cytokinin a plant hormone?
It has been recognized that cytokinins are plant hormones that influence not only numerous aspects of plant growth, development and physiology, including cell division, chloroplast differentiation and delay of senescence but the interaction with other organisms, including pathogens.
Which hormone is antagonistic to abscisic acid?
gibberellins
– So there is a hormone that behaves as an antagonist to the Abscisic acid which is gibberellins. – Gibberellins is also a plant hormone, where it Regulates the various developmental processes.