Answer:
c. independent variable
Explanation:
#<em>c</em><em>arryonlearning</em>
The origin of life<span> on Earth is a set of paradoxes. In order for </span>life<span> to have gotten started, there must have been a genetic molecule something like DNA or RNA capable of passing along blueprints for making proteins, the work horse molecules of </span>life<span>.</span>
Answer:
<h3>is formed when hydrogens combine temporarily with pyruvate..</h3>
Answer: The following is a <u>postzygotic isolating barrier </u>:
- The hybrid offspring of two species of crocodiles can produce normal gametes but cannot obtain a mate.
Explanation:
<em><u>Reproductive isolation </u></em>occurs when <em>barriers prevent</em> two populations from interbreeding , <u>keeping their gene pools separate.</u>
We can find the Prezygotic isolation that occurs<u> before fertilization </u>can happen.
And the Postzygotic insolation barriers are the reproductive insulation processes that<u> act after the mating</u>. They are all that concern the viability of the individuals produced.
Prezygotic isolation barriers can be temporal, behavioural, geographic , ecological or mechanical; whereas postzygotic isolation barriers include the inviability, infertility or breakdown of hybrid organisms
Ans.
Sickle-cell disorder shows defected red blood cells, due to mutation in gene that code for hemoglobin. The mutated genes for sickle-cell disease are found in higher percentage of sub-Saharan African population as it provides protection against malaria as compared to population of United States.
Malaria is common in sub-Saharan Africa region and there, natural selection favored gene for sickle cells, because it might be beneficial to people having sickle cell disease that makes them able to survive in such condition and transmit their genes to offspring.
On the other hand, in those Africans, who moved to United States, where malaria is uncommon or absent, natural selection favored normal, wild type genes, resulting in fewer people with defected sickle cell.
Thus, the evolutionary process behind this is 'natural selection.'
