There are guard cells surrounding each stoma that cause them to open or close throughout the life cycle of the plant. This occurs in response to water and ions concentration in the plant cell.
Answer:
1. They must be removed before sister chromatids or homologous chromosomes can separate
Explanation:
During the S-phase of the cell cycle, not only does DNA have to be replicated, but also newly synthesized DNA molecules have to be connected with each other. This replicated DNA (sister chromatids) remain physically connected with each other from S phase until metaphase. This physical connection is called Sister chromatids cohesion.
Sister chromatid cohesion depends on COHESIN, a tripartite protein complex that forms a ring structure to hold sister chromatids together during mitosis and meiosis. Cohesin regulates the separation of sister chromatids during cell division, either mitosis or meiosis. This sister chromatid cohesion is essential for the biorientation of chromosomes on the mitotic or meiotic metaphase spindle, and is thus an essential prerequisite for chromosome segregation. Without the cohesion, sister chromatids would not be segregated symmetrically between the forming daughter cells, resulting in aneuploidy.
Cohesion is established during S-phase of DNA replication, and the cohesins hold the sister chromatid together after DNA replication until anaphase when the removal of cohesin leads to separation of sister chromatids (meiosis II and mitosis) and homologous chromosomes (meiosis I).
Answer:
They would be smaller than their normal size.
Explanation:
The G2 phase of a cell's cycle is where the cell starts preparing itself for the mitosis by producing proteins and growing in size. If the G2 phase of the parent cell is shortened, then the cell is not able to grow as much as it needs but this does not affect the mitosis process, the daughter cells would be much smaller due to the parent cell's size.
I hope this answer helps.
~Hello there!
Your question: <span>The ______ in lycophytes are called microphylls.
Your answer: </span>The leaves in lycophytes are called microphylls.
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