b. both sexually and asexually
Answer:
1 . The stage on the first meiotic division when the homologous chromosomes move to opposite poles but the sister chromatids remain together
: b. Anaphase I
2 . The stage in the second meiotic division where sister chromatids migrate to opposite poles
: c. Anaphase II
3 . A structure on the chromosome that holds a pair of chromatids together during replication
: f. centromere
4 . A double-stranded chromosome following replication attached by a centromere
: d. chromatid
5 . A condition where non-sister chromatid of homologous chromosomes exchange genes
: e. crossing over
6 . The stage in the first meiotic division where the homologous chromosomes line up as a pair
: a. Metaphase I
7 . The stage in the second meiotic division where the chromatid pair lines up at the equator of the cell: g. Metaphase II
Explanation:
DNA replication occurs during the S phase of the interphase of the cell cycle. The replicated DNA molecules are accommodated in two sister chromatids of a chromosome that are held together by a centromere.
During prophase I, the chromatids of a homologous chromosome pair exchange a genetic segment. This process is called crossing over. It generates recombinant chromatids with new combinations of genes.
Metaphase I of meiosis I includes the alignment of homologous pairs of chromosomes at the cell's equator. This is followed by separation and movement of homologous chromosomes to the opposite poles of the cell during anaphase I.
Metaphase II of meiosis II includes the alignment of individual chromosomes, each with two sister chromatids, on the cell's equator. During anaphase II, splitting centromere separates the sister chromatids which then move to the opposite poles of the cell.
Answer:
Due to the dense atmosphere
The magnetic field of the earth
Explanation:
Most particles in the solar wind do not reach the earth's surface because the atmosphere is very dense and the protecting magnetic field of the earth.
A solar wind is a burst of energetic particles from the sun which are made up electrons, ions, etc.. They travel at a very high velocity.
- The magnetic field of the earth is able to deflect these charged particles away.
- In areas such as the pole, the interact with the atmosphere to produce very stunning auroras.
a. chloroplast and cell wall
The chloroplast contains chlorophyll, which is the stuff that makes plants green. So animals do not have a chloroplast. Only plants have a cell wall and it is what helps plants maintain their shape. Hope this helped! :)