Answer:
What sends oxygenated blood back to the heart from the lungs?
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
Explanation:
Answer:
The ability of species of living beings to overproduce offspring
Explanation:
Darwin proposed that species have the ability to produce offspring at a rate that could cause a geometric increase in the population size. This is called biotic potential. The overproduction of offspring causes intraspecific competition for the limited available resources. Darwin reasoned that the overproduction of progeny leads to a struggle for existence between the individuals of a population. He observed that the struggle for existence does not allow the population size of species to grow geometrically.
Answer:
The answer is D.) Mercury
The answer is invasive species.
Invasive species are species that are not native to specific ecosystem,
but they have a capability to spread widely through the ecosystem, This way
they can threaten native species of the ecosystem or cause
environmental harm.
<span>After being introduced into the Black Sea, they greatly affect local
ecosystem. In the new area, they have no natural predators and are able to
spread. If they spread beyond the area they are introduced, they
become invasive species which can overgrow native biotopes and are
a great threat to the local biodiversity. This could lead to the extinction
of some native species.</span>
In complementary base pairing, the G pairs with C, and A pairs with T. Given that this be the rule, the complementary nucleotides for your sequence would be as follows: CGATTAACGTAGGCA.
With regards to proofreading, mutations in cell division occur once in around every 100,000 base pairs. If this happens, the enzyme that pairs the nucleotides to form DNA, called DNA polymerase, detects the error and moves back along the strand, it then cuts the incorrect nucleotide and replaces it with the correct one, fixing the error and continuing with the DNA synthesis.
This process corrects the majority of errors in DNA synthesis, but some errors can still be missed by the DNA polymerase, this is then rectified by a protein complex which binds to the incorrect pairing until anther complex, comes along and cuts that particular section of DNA out, which is then replaced by a new section of correct nucleotides synthesized by the polymerase enzyme, the two sections at either end that were cut is then sealed by ligase, an enzyme which essentially "glues" the DNA stands back together.
My apologies for the long answer, I hope I answered your question and that you understand it well enough.