Different structures and functions of roots
Explanation:
Roots are the underground descending non-green part of the plant.
Root functions: Anchorages the plant to the soil, absorbs water and nutrients from the soil.
Characteristics: Positively geotropic and hydrotropic, negatively phototropic; does not have nodes, internodes or stems.
Types:
- Tap root
- Adventitious root – fibrous, foliar and true adventitious roots
Structure and functions:
- Root cap or Calyptra: Cap-like structure covering the root tip
.
- Function: protects the meristematic tissues of the root, secretes mucilage which enhances the root tips to grow into the hard soil.
- Meristematic zone or growing point sub-terminal behind root cap. These cells are inverted and looks like a dome.
- Function – helps in the root growth by adding new cells to the root tip and other basal regions
- Zone of elongation behind the meristematic zone.
- Function – helps in elongation of the root
- Root hair zone: This is the zone of differentiation where cells differentiate into vascular tissues like phloem, xylem, endodermis, cortex etc.
- The main function of root hair is to increase the total surface area of root to facilitate more absorption of water and other nutrients from the soil
- Zone of maturation: the major and mature portion of a root.
- Function - lateral roots originates from this zone and radial differentiation leads to secondary growth.
It would be completely false to state that adult <span>brains have about five times the number of connections that a three-year-old has. The correct option among the two options that are given in the question is the second option. A child brain has twice as many connections than that of an adult brain. </span>
Answer:
good question, you don't. Or simply wait untill you finish choking bart
Mitosis begins with prophase, during which chromosomes recruit condensin and begin to undergo a condensation process that will continue until metaphase. In most species, cohesin is largely removed from the arms of the sister chromatids during prophase, allowing the individual sister chromatids to be resolved.
Prometaphase begins with the abrupt fragmentation of the nuclear envelope into many small vesicles that will eventually be divided between the future daughter cells. The breakdown of the nuclear membrane is an essential step for spindle assembly.
Next, chromosomes assume their most compacted state during metaphase, when the centromeres of all the cell's chromosomes line up at the equator of the spindle. Metaphase is particularly useful in cytogenetics, because chromosomes can be most easily visualized at this stage. Furthermore, cells can be experimentally arrested at metaphase with mitotic poisons such as colchicine.
The progression of cells from metaphase into anaphase is marked by the abrupt separation of sister chromatids. A major reason for chromatid separation is the precipitous degradation of the cohesin molecules joining the sister chromatids by the protease separase.
Mitosis ends with telophase, or the stage at which the chromosomes reach the poles. The nuclear membrane then reforms, and the chromosomes begin to decondense into their interphase conformations. Telophase is followed by cytokinesis, or the division of the cytoplasm into two daughter cells. The daughter cells that result from this process have identical genetic compositions.
The answer is genes and not jeans.
