Miosis. Explain briefly.
Answers
Answer:
Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information. These cells are our sex cells – sperm in males, eggs in females. During meiosis one cell? divides twice to form four daughter cells.
Interphase
Cells in interphase carry out various processes, such as replicating DNA and chromosomes and synthesizing proteins. Interphase occurs during meiosis I.
Prophase I
Replicated chromosomes of two sister chromatids become visible during this stage as they begin to condense and form pairs. Synapsis, or the exchange of chromosome segments, then takes place between the paired chromosomes and genetic information is exchanged. During this process, the nucleur envelope has broken down and centrioles with spindle fibers have moved to opposite ends of the cell. Prophase occurs during meiosis I.
Metaphase I
The homologous chromosomes line up as pairs at the equator of the cell. Spindle fibers then attach to the centromere of each homologous chromosome. Metaphase occurs during meiosis I.
Anaphase I
The homologous chromosomes separate, as each pair is then guided by spindle fibers and moved to opposite ends of the cell. The chromosome number is reduced from 2n to n when the chromosomes seperate. Each chromosome still consists of two sister chromatids. Anaphase I occurs during meiosis I.
Telophase I
The homologous chromosomes, consisting of two sister chromatids, reach opposite ends of the cell to form to nuclei. The sister chromatids might not be identical due to crossing over during synapsis in prophase I. Each pole contains only one member of the original pair of homologous chromosomes. The cell then divides. Telephase I occurs during meiosis I.
Prophase II
Chromosomes condense, spindle fibers form in each new cell, and spindle fibers attach to chromosomes. Prophase II occures during meiosis II.
Metaphase II
Centromeres of chromosomes line up randomly at the equator of each cell. Metaphase II occurs during meiosis II.
Anaphase II
The centromeres split and the sister chromatids separate and move to opposite poles. Anaphase II occurs during meiosis II.
Telophase II
Four nuclei form around the chromosomes, the spindle fibers break down, and the cells divide. Telophase II occurs during meiosis II.
Cytokinesis
Four cells have formed and each nucleus contains a haploid number of chromosomes. Cytokinesis occurs during meiosis II.
Explanation:
Answer:
Miosis, or miosis is exercise construction of the pupil. the term is from ancient Greek muein to close the eye". the opposite condition mydriasis, dilation of the pupil Anisocoriya is the one of condition of one pupil being more dilated than the other