Answer:
With each heartbeat, the heart sends blood throughout our bodies, carrying oxygen to every cell. After delivering the oxygen, the blood returns to the heart. The heart then sends the blood to the lungs to pick up more oxygen.
The symbiotic relationship between moss and a tree is commensalism
the negative impact is that the air will get polluted and also that we will have less trees so less oxygen since they will be building more structures and factories and plenty of other stuff, that will lead to chopping up plenty of trees.
The replacement rate is the level at which a population remains stable.
<span>Replacement rate (level) is the fertility rate and represents the average number of children born per woman at which a population<span> exactly replaces itself from one generation to the next (without migration). More precisely, </span>it is the amount of fertility needed to keep the population the same, from generation to generation. As a result of the total <span>fertility rate,</span><span> there will be no increasing or decreasing of the population, it will be stable. </span></span>
