B, the independent variable because this is the one that is purposefully changed in an experiment to test the hypothesis.
Because the soil didn't have the same nutrients it has now due to lack of decomposition of other plants and animals.
<span>The sex cells, more scientifically known as the ova and spermatozoa, are composed of 23 of the usually 46 human chromosomes. They have half the usual number because they of course combine to form a new, genetically distinct, cell, termed the zygote. The correct term for this type of cell, one with half of the complete genome, is GAMETE. Therefore the answer is option (a).</span>
A
Planting the same crop over and over again depletes the nutrients of the soil and it also allows any pests to get used to the soil. That’s why many people practice crop rotation.
To show the carbon cycle in a bottle ecosystem. A bottle ecosystem is to recreate an ecosystem inside a bottle or a container to study them or just for decoration. ... The second thing that happens in the ecosystem is that the pondweed absorbs the carbon dioxide converting it into oxygen by the process of photosynthesis.
