How are auxins able to cause a stem to grow upright?

Answer 1

• HERBACEOUS STEMS
• Herbaceous~ description of a plant whose stem has little or no woody tissue
• -In cold climates, herbaceous plants die back to their roots every year. For example, perennials such as Chrysanthemums and tulips grow new leaves and stems every spring. In tropical climates, the above ground parts of both woody and herbaceous plants can grow throughout the year.
• *Most herbaceous plants are annual and their stems grow longer at the tip as the cells divide in the apical meristem.

  -The apical meristem is a plant structure containing meristematic tissue that divides, allowing stems and roots to grow in length.

• Cytokinins is a hormone that acts as a retarding agent in plant growth. This hormone also works with auxin to stimulate cell division and more.
• There are five types of plant hormones. Each hormone has a specific function that is directly related to the concentration of the hormone, its site of action, and the developmental stage of the plant. The cytokinins hormone is the second hormone that synthesizes the roots and transports them to other organs.
• Cytokinins is defined as a class of related plant hormones and retard aging and act in concert with auxin to stimulate cell division, influence the pathway of differentiation, and control apical dominance.
• In the 1940's cytokinins were discovered by Johannes van Oberbeek. He was conducting trial-and-error experiments to find chemical additives that could enhance growth and development of plant cells. While he was working he found growth of plant cells could be stimulated by adding coconut milk. Then ten years later Folke Skoog and Carlos O. Miller induced tobacco cells that were being grown in a culture to divide by adding degraded samples of DNA. In each experiment the additives were forms of adenine. From this the growth regulators where names cytokinins because they stimulate cell division or cytokinesis.
• Growing tissue are where cytokinins are produces. They reach their target area by moving up the xylem sap. Working with auxin the cytokinins influence the pathway of differentiation as well as stimulating growth. A sample of parenchyma tissue is cultivated without cytokinins, the cells grow very large but cannot divide. Then if just cytokinins are added there will be no effect. Yet if the cytokinins are added with auxin then the cells will divide. The differentiation of cells is based on the cytokinins to auxin ratio. If there is more auxin then cytokinins roots will form. If vise versa shoots buds develop from the callus. Yet if the ratios are equal the mass of cells will continue to grow but it remains an undifferentiated callus. These hormones stimulate RNA and protein synthesis.
• The control of the apical dominance is an interaction between cytokinins and auxin. When the terminal bud suppresses the development of auxiliary buds. This cases is an example of when the two hormones are antagonistic. When the auxin transports down the shoot it restrains auxiliary buds from growing which allows the shoot to lengthen. Yet if cytokinins are entering the shoot systems they signal the auxiliary buds to start growing. Auxin cannot stop the buds from growing once it has begun.
• The coordination between auxin and cytokinins allow a balance of growth in the shoots and roots systems. When the roots become more extensive they cytokines level increase and signals the system to form more branches. Once the roles are reversed in the development of the lateral roots; cytokinins inhibit root branching while auxin stimulates. Growth of the auxiliary buds are regulated by both auxin and cytokinins are still effected by one more hormone, ethylene.
• Cytokinins can slow down the aging of some plant organs. This may be because they are inhibiting protein breakdown, by stimulating RNA and protein synthesis. If you took leaves from a plant and dipped them into a cytokinins solutions, they would stay green much longer. Fresh cut flowers are often sprayed with cytokinins spray to make them last longer
• ENGLISH
• Auxins cause cells to grow longer on the sunny side of the stem. This is because auxins are plant
• Auxins loosen up the cell walls which allows the cell to elongate.
• Cells grow in number, but not in size. Cells are always very small since they must retain a high
• TAGALOG
• Auxins ay maging sanhi ng mga cell upang palaguin na sa maaraw na bahagi ng stem. Ito ay dahil auxins ay halaman

  Auxins buhaghagin ang mga pader ng ​​cell na nagbibigay-daan sa cell na pahabain.

  Palaguin ang mga mga cell sa numero, ngunit hindi sa laki. Mga cell ay palaging napakaliit dahil dapat silang kumuha ng isang mataas na

Answer 2

Auxins promote cell elongation on one side of the stem, causing it to bend towards the opposite side. This differential growth elongates one side of the stem more than the other, resulting in the stem bending, and ultimately growing upright.

Answer 3

causes cells to elongate