The correct term to fill in the blank would be cortisol. In the context of stress hormones and the brain, cortisol has a profound effect on the hippocampus, a brain structure that plays a pivotal role in memory. Cortisol is classified as a steroid hormone which is produced by the adrenal gland. It is deemed as the stress hormone as it is released as a response to stress as part of the fight or flight process. From studies, cortisol was found to have effect on the hippocampus when present in high levels. It damage and kill the cells in that area of the brain. The hippocampus is the area of the brain that is responsible for the long term memory storage. So, when this part is damage then the storage for our memories would surely be affected.
<span>Characteristics that mentioned biomes have in common are:
- They are all forests, dominated by trees and other woody vegetation.
- They inhabit animal life with great microbial diversity.
- They all have big carbon sinks.
Still, trees different in a number of ways in these three biomes:
- </span><span>Tropical rainforest: Trees are evergreen and have large green leaves. Canopy is multilayered and dense, so there is a little light in the forests.
- </span><span>Temperate deciduous forest: Trees are deciduous, leaves are lost annually. Canopy is moderately dense, so there is more light than in tropical rainforests.
- </span><span>Boreal forest: Trees are evergreen conifers with needle-like leaves. Canopy is thick and permits low light penetration.</span>
Unlike other ways of reproduction, sexual reproduction provides variation through inheriting various genes. This variation is essential for adaptation as it would not just create a copy of the original life form, but rather a different unique life form that could adapt to something, and then have it's own offspring with the adapted trait.
