A sudden shift in the tectonic plates of the earth
By all plants, algae, and some microorganisms
Answer:
In nature, limiting factors affecting population sizes include how much food and/or shelter is available, as well as other density-dependent factors. Density-dependent factors are not relevant to populations that are below "carrying capacity," (i.e., how much life a habitat can support) but they start to have to become noticeable as populations reach and exceed that limit. The degree of control imposed by a density-dependent factor correlates to population size such that the effect of the limitation will be more pronounced as population increases. Density-dependent factors include competition, predation, parasitism and disease.
Competition
Habitats are limited by space and resource availability, and can only support up to a certain number of organisms before reaching their carrying capacity. Once a population exceeds that capacity, organisms must struggle against one another to obtain scarce resources. Competition in natural populations can take many forms. Animal communities compete for food and water sources whereas plant communities compete for soil nutrients and access to sunlight. Animals also vie for space in which to nest, roost, hibernate, or raise young, as well as for mating rights.
Predation
Many populations are limited by predation; predator and prey populations tend to cycle together, with the predator population lagging somewhat behind the prey population. The classic examples of this are the hare and the lynx: as the hare population increases, the lynx has more to eat and so the lynx population can increase. The increased lynx population results in more predatory pressure on the hare population, which then declines. The drop in food availability in turn causes a drop in the predator population. Thus, both of these populations are influenced by predation as a density-dependent factor.
Parasitism
When organisms are densely populated, they can easily transmit internal and external parasites to one another through contact with skin and bodily fluids. Parasites thrive in densely packed host populations, but if the parasite is too virulent then it will begin to decimate the host population. A decline in the host population will in turn reduce the parasite population because greater distance between host organisms will make transmission by more difficult.
Disease
Disease is spread quickly through densely packed populations due to how close organisms are to one another. Populations that rarely come into contact with one another are less likely to share bacteria, viruses and fungi. Much like the host-parasite relationship, it is beneficial to the disease not to kill off its host population because that makes it more difficult to for the disease to survive.
Answer:
Impact.
Explanation:
Science can be defined as a branch of intellectual and practical study which systematically observe a body of fact in relation to the structure and behavior of non-living and living organisms (animals, plants and humans) in the natural world through experiments.
In Science, the study of blood is generally referred to as serology.
Impact refers to how fast blood traveled from its source to where it landed.
This ultimately implies that, an impact is a measure of the rate at which blood travels from its source to where it lands. The four (4) phases of impact includes;
I. Displacement.
II. Retraction.
III. Contact and collapse.
IV. Dispersion.
In Human anatomy, cardiac cycle can be defined as a complete heartbeat of the human heart which comprises of sequential alternating contraction and relaxation of the atria and ventricles, therefore causing blood to flow unidirectionally (one direction) throughout the human body.
Generally, the cardiac cycle occurs in two (2) stages;
Diastole : in this stage, the ventricles is relaxed and would be filled with blood.
Systole: at this stage, the muscles contracts and thus, allow blood to be pushed through the atria.
Generally, the right atrioventricular valve (AV) is also referred to as the tricuspid valve and is located on the right dorsal side of the human heart. The right atrioventricular valve (AV) comprises of three (3) leaflets (flaps) which opens and closes in order to allow for the flow of blood from the right atrium of the human heart to the right ventricle. Also, the right atrioventricular valve is saddled with the responsibility of preventing blood from flowing backward in the mammalian heart.
