Answer:
Uncontrolled cell division can lead to the formation of masses of cells that can remain in a place called <u>primary </u>tumors or ones that can move called <u>metastatic </u>tumors.
Explanation:
The term primary tumor refers to the original tumor, a place where the tumor first appeared.
Metastatic tumors are tumors that appear in other organs and originate from the primary tumor. Tumor cells can break away from the primary tumor and travel to other locations in the body through the blood or lymph system and form new tumors. This is how metastatic tumors appear.
For example, a brain tumor is a primary tumor if it first appeared in the brain. A metastatic brain tumor is a tumor that appeared in another organ and then spread to the brain.
Explanation:
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An ecological pyramid (also trophic pyramid, Eltonian pyramid, energy pyramid, or sometimes food pyramid) is a graphical representation designed to show the biomass or bioproductivity at each trophic level in a given ecosystem.
A pyramid of energy represents how much energy, initially from the sun, is retained or stored in the form of new biomass at each trophic level in an ecosystem. Typically, about 10% of the energy is transferred from one trophic level to the next, thus preventing a large number of trophic levels. Energy pyramids are necessarily upright in healthy ecosystems, that is, there must always be more energy available at a given level of the pyramid to support the energy and biomass requirement of the next trophic level.
A pyramid of energy shows how much energy is retained in the form of new biomass at each trophic level, while a pyramid of biomass shows how much biomass (the amount of living or organic matter present in an organism) is present in the organisms. There is also a pyramid of numbers representing the number of individual organisms at each trophic level. Pyramids of energy are normally upright, but other pyramids can be inverted or take other shapes.
Ecological pyramids begin with producers on the bottom (such as plants) and proceed through the various trophic levels (such as herbivores that eat plants, then carnivores that eat flesh, then omnivores that eat both plants and flesh, and so on). The highest level is the top of the food chain.
a scientific model is a model used to test theories. sometimes scientist use rats as a scientific model
<span>Cytokinesis takes place by formation of a cell plate in plant cells, and a cleavage furrow in animal cells. Cytokinesis is the process of cell division. Cell plates are found in plants and some algae. Cleavage furrows are found in animals and some algae as well.</span>
Answer:
Genetic drift is a mechanism of evolution in which allele frequencies of a population change over generations due to chance (sampling error).
Genetic drift occurs in all populations of non-infinite size, but its effects are strongest in small populations.
Genetic drift may result in the loss of some alleles (including beneficial ones) and the fixation.
Genetic drift can have major effects when a population is sharply reduced in size by a natural disaster (bottleneck effect) or when a small group splits off from the main population to found a colony (founder effect).
