Answer - Theory
Reasoning - Your best bet and term to describe the evolution by natural selection is theory as to still scientific theory/research is still ongoing and changes can be made in a different direction.
Answer:
To conclude, you cannot prove a hypothesis because you can never generalise the results to the whole population and foresee the results will always be the same in the future. You can however, reject the null hypothesis consistently, through statistical hypothesis testing so that the theory becomes highly likely to be true, but not proven.
Explanation:
<span>I'm assuming this in plants.
Brief-ish answer:
"Fertilization in plants occurs when pollen grains are transported from anthers to stigma. When ripe pollen from an anther catches on the stigma of the same kind of flower, each pollen grain sends out a small thread-like tube."
Here's a fuller answer:
"</span>Fertilization occurs after pollination, when pollen grains land on the stigma of a flower of the same species. During this time, a series of events take place leading to the formation of seeds. A pollen grain on the stigma develops a tiny tube that runs down the style of the ovary. The pollen tube contains a male gamete which meets the female gamete in the ovule. Fertilization occurs when the two gametes combine and their chromosomes join. The resulting product is a normal complement of chromosomes, with some from either parent flower. The fertilized ovule forms a seed, which consists of a food reservoir and an embryo that later develops into a new plant. In gymnosperms (conifers) male gametes are enclosed in pollen grains and are transmitted by wind or insects to the female reproductive organs. Fertilization in angiosperms (flowering plants) occurs when insects or other animals transport the pollen to the female reproductive organ (pistil).<span>
</span><span>Fertilization is the fusion of gametes to launch the development of a new individual organism. In animals, the process entails the combination of ovum with a sperm, leading to the development of an embryo. Fertilization in plants occurs when haploid gametes meet to create a diploid zygote, which eventually forms an embryo.</span><span>"
source: </span>https://www.reference.com/science/plant-fertilization-occur-ccf48c80e72fc410
