Answer:
increase anxiety; decreased vulnerability to overreact to stress
Explanation:
Serotonin (5-HT) is a natural neurotransmitter that carries signals between nerve cells (neurons) throughout the body. This neurotransmitter (serotonin) is responsible for regulating many biological functions (e.g., mood, digestion, sleep, etc). Moreover, it has been shown that there is an association between low cerebrospinal fluid 5-hydroxyindole-acetic acid (5-HIAA, the principal serotonin metabolite in the brain) levels and the risk of developing depression or destructive behaviors. In addition, serotonin concentration can also be elevated in situations of anxiety and/or stress. Antidepressants such as Prozac, Zoloft and Paxil act as serotonin uptake inhibitors that increase serotonin concentration at the synaptic site. Like other drugs, these antidepressants may lead to increase anxiety and decrease the vulnerability to react to stress by downregulating sensitivity to serotonin released during natural stress situations.
Explanation:
Oxygen and nutrients from food must be absorbed into the bloodstream to be delivered to cells for respiration. Waste materials such as carbon dioxide must be removed from cells into the bloodstream. Tissues contain capillary networks to allow these exchanges to occur at a cellular level.
The correct answer is option C, that is, have poor soils with little organic matter.
In the tropical rain forests, only a thin covering of decaying organic matter is present. The majority of the tropical rainforest soils are comparatively poor in nutrients. The torrential rains and millions of years of weathering have washed the majority of nutrients out of the soil.
In the tropical rain forests, the soils are generally poor in nutrients and all the nutrients are captivated in the living species. The soils in various regions of the tropical rain forests are laterite soils.
It is called the Milky Way because it appears as a milky band of light in the sky when you see it in a really dark area. Just as the Earth goes around the Sun, the Sun goes around the center of the Milky Way.
Answer:
The variation might occur in the population that leads to the evolution of the species. This variation may occur due to natural selection, mutation or recombination.
The variation might change the genotype and allelic frequency of the population and might also change the phenotype of the individual in the population. The breeding adults of the left mouthed in 1981, 1987 and 1990 shows variation and was equally opposite phenotype which is more common in the population.