The complete question is :
The success of plants extending their range northward following glacial retreat is best determined by _____.
A) whether there is simultaneous migration of herbivores
B) their tolerance to shade
C) their seed dispersal rate
D) their size
Answer: The seed dispersal rate
Explanation:
The seed dispersal can be defined as the movement of the seeds away from the parent plant. The ability of the plant to extend is completely dependent on the ability of the plant to disperse its seeds.
Plants have very limited ability, they need vectors to carry its seed from one place to another.
The biotic and abiotic vector both are involved in carrying the seeds which helps in expansion of the trees.
hence, the correct answer is option C
Answer:
B
Explanation:
Water moves from higher potential to lower potential i.e it moves from surounding to the cell.
The answer is <span>Anaphase I separates homologous chromosomes and anaphase II separates sister chromatids into daughter cells.</span>
Meiosis is a cell division which results in the reduction of chromosome number by half - from diploid to haploid - in daughter cells. It consists of meiosis I and meiosis II. Meiosis I produces two haploid cells. Meiosis II is analogous to mitosis, so in total, meiosis results in four haploid cells. So, in meiosis, there are two anaphases - the anaphase I in meiosis I and the anaphase II in meiosis II.
<span>In anaphase I, the sister chromatids separate from each other to the opposite sides of the cells. In meiosis I there are 46 chromosomes in duplicate, which are present as pairs of sister chromatids. In anaphase of meiosis II, since the cell is haploid, there are 23 chromosomes in duplicate, which are present as sister chromatids.</span>
The vegetation of the tundra is composed of shrubs, grasses, mosses, lichens. Tree vegetation is very rare because of low temperature and short growing season.
