D. Cyanobacteria one of the first beings
Answer:
Using the food chain which originates from the sun's energy.
Explanation:
The main benefit of crossing over is that it increases genetic diversity.
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Crossing over and
Genetic Diversity</h2>
Crossing over ensures that the daughter cells produced are genetically more diverse than their parent cells.
The exchange of chromosomal segments makes the chromosomes of the daughter cells to be more sophisticated than that of their parents.
Increased genetic diversity in daughter cells increases their chances of survival as more genes are present in their genomes that could potentially make them more adaptable to the environment.
In summary, crossing over increases genetic diversity and genetic diversity increases the chances of survival in the face of changing environment.
More on genetic diversity can be found here: brainly.com/question/1446827?referrer=searchResults
D) no change in cardiac output, increased heart rate, decreased stroke volume occurs after blood donation
Explanation:
When a person donates blood, there is a slight loss of blood volume or hypovolemia. This triggers the baroreceptors of the blood; although does not trigger the osmoreceptor.
The baroreceptor responses are according to the arterial pressure which rises momentarily and results in increased sympathetic activity with decreased vagal activity.
These changes will lead to vasoconstriction, reduced stroke volume, increased heart rate or tachycardia which helps to maintain the cardiac output.
The soreness at the venepuncture site on the skin is due to bruising which is common after any needleprick. applying cold pack, elevating and resting the arm.
In order to compensate for the fluid volume loss and avoid dehydration, one must take plenty of fluids before and after blood donation.