Answer:
O.
Explanation:
There are different types of soils and it is made up of different layers or horizon such as A, B, C, O, R and E. Together all the horizons forming soil profile. Each horizon containing different soil types.
O horizon: Known as top layer of the soil which contains layer of organic matter which is about two inches thick, and made up of humus such as decomposing leaves, dark-colored, carbon rich matter, twigs and microbial biomass which is mixed with small grained minerals for the formation of aggregate structures.
Within a gymnosperm megasporangium, the following developmental sequences that are correct, assuming fertilization occurs is: megaspore, female gametophyte, egg cell, sporophyte embryo. The last Option (Option D) is correct.
In gymnosperm megasporangium, the meiotic division produces four haploid megaspores from a single cell, three of which generally degenerate. The female gametophyte is formed by mitosis from the surviving megaspore.
Prior to fertilization, the male mature gametophyte needs to be transferred to the female gametophyte for fertilization to take place.
When the nuclei of the sperm encounter the nucleus of the egg cell in gymnosperms, it fuses with the egg nucleus to produce a diploid zygote.
Mitosis occurs in the fertilized egg to initiate the growth of a new sporophyte generation (the multicellular embryo of the seed.)
Therefore, we can conclude that we've understood the mechanism of developmental sequence in the gymnosperm megasporangium.
Learn more about the gymnosperm here:
brainly.com/question/4526473?referrer=searchResults
Hmm.this one is complicated .many factors affect the amount of solar energy an area receives but mainly the length of the solar rays.places close to the equator are hotter because the rays are short and the travel less distance.but away from the equator the rays are longer
In the nucleus, the part on the cell that contains all the genome
