It seems that you have missed the necessary options for us to answer this question so I had to look for it. Anyway, here is the answer. Varicose veins seen in the superficial veins of the legs are unsightly and often treated by surgically removing them. however, even without these veins being present, the return of all blood toward the heart from the legs is not diminished primarily because <span>blood can still return via the deep veins. Hope this helps.</span>
Answer:
A
Explanation:
You will always be going uphill which shows a negative acceleration, the other choices have changes of speed or going downhill.
Ecological pyramids are graphical representations of the trophic structure of an ecosystem. Regarding these pyramids, check the incorrect alternative.
A) A pyramid is called a number pyramid when it tells you how many individuals there are at each tropic level.
B) The biomass pyramid can be inverted.
C) An energy pyramid can never be reversed.
D) The base of a pyramid is not always represented by the producer. E) A biomass pyramid represents the amount of organic matter found at each tropic level
C. is the wrong option. This is because it represented the energy fixed in each tropic level . it is never inverted because it flow upwards in the ecosystem. This energy reduces upwards the pyramid, it is largest at the base of the producers, and decreases in amount as it flow upwards from one organism at each trophic level to another. This is because each organism uses the energy for biological work
Answer:
Explanation:
Answer:
<u>the bottleneck effect</u>
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Explanation:
Genetic drift has an important impact on the small populations. mutations, which are spontaneous heritable changes in the genetic code, made up of DNA. Here, mutations accumulate over time in a group, modifying the distribution of alleles or various forms of a gene. Natural selection may result in a loss of diversity in a population called genetic drift; one trait's allelic frequency rises while others become less prevalent. Typically such differences exist because of occurrences of mutation and recombination.
Some mutations or alleles may become extinct from the population.
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Variants of a gene accumulate and are transmitted across generations; the frequencies of these occurrences are altered and become more stable in genetic drift- they become genetically distinct and may eventually form a new species after isolation. This may be further compounded through other phenomena such as the founder effect where a group separates and genetic diversity decreases; and the bottleneck effect where barriers to reproduction or the die-off a population increases genetic drift.
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Answer and Explanation:
The lymph node are the sites for the formation of lymphocytes and monocytes. These are concerned with antibody formation and phagocytosis of foreign materials respectively. In the lymph nodes, bacteria and other harmful materials are removed from lymph.
