Answer:
The correct answer is option 4.
Explanation:
Viruses cannot be considered alive as they cannot carry out metabolic reactions on their own. Metabolism signifies the tendency to gather and use energy. The chemical reactions in the cells spontaneously change the molecules into the forms of energy, which can be utilized by the organism.
However, in the case of viruses, they are too small and simple to collect and utilize their own energy. They are completely dependent upon the host cells for energy. The viruses only require energy when they need to make duplicates of themselves, however, they do not require any energy when they are present outside of the cell. Thus, as they cannot carry out metabolic reactions, they are not considered as living.
<span>Smell often trigger vivid memory<span>. This is because of the anatomy of the olfactory pathway. The nasal mucosa senses odorant molecules wherein the olfactory nerve will transduce the signal to the olfactory bulb to the olfactory cortex, bypassing the thalamus (unlike other senses) Anatomically and physiologically, the olfactory cortex is closely related to the amygdala which is associated with memory formation.
</span><span><em>Primary example is that a certain smell of a perfume of your ex-lover can trigger vivid memories even if it was many years ago.</em></span></span>
An ecologist studying plants in the desert performed the following experiment. She staked out two identical plots, which included a few sagebrush plants and numerous small, annual wildflowers. She found the same five wildflower species in roughly equal numbers on both plots. She then enclosed one of the plots with a fence to keep out kangaroo rats, the most common grain-eaters of the area. After two years, to her surprise, four of the wildflower species were no longer present in the fenced plot, but one species had increased dramatically. The control plot had not changed. Using the principles of ecology, propose a hypothesis to explain her results.
Explanation:
- This example highlights the impact of plant predation on species selection. In the fenced off plot animal predation is not a factor on plant selection.
- In this case plants will compete for resources only with each other and in this case one plant had a selective advantage over the other 3 species of plants. In the plot exposed to animal predation the ratio of the four species is equal.
- This is likely do to an increased preference of animals for the plant species that dominates in the fenced off plot and/or anti-animal predation tactics by the other three species.
a.Hypothesis: kangaroo rats are keystone species
-Reintroduce kangaroo rats (and the other locally extinct species)
-Should observe equilibrium re-established
b.Hypothesis: kangaroo rats exert top-down control on community
-Reintroduce kangaroo rats (and other locally extinct species)
-Increase kangaroo rat population in other plot
-Decrease (but don't eliminate) kangaroo rat population in other plot
c.Hypothesis: Locally extinct species inferiorly competed with the extant species of plant
-Remove surviving species from other plot (and remove kangaroo rat population)
Answer:
Plant cells carry chloroplasts: organelles containing the pigment chlorophyll, which they employ to entrap sunlight
Hope this helps!