Developed a way to protect their foliage. Instead of flat leaves, pine trees have needles<span>. These </span>needles<span> are the key to the Winter survival of the </span>pine tree<span>. </span>Needles<span> cut evaporation so</span>trees<span> can save water!
Cacti have sines instead of leaves because they help protect them from getting eaten and they don't need leaves because they store water inside themselves.
They both have adapteations to help them servive in very harsh conditions. Cacti use their adaptations to survive in scourching heat and pine trees can servive in freezing cold.</span>
It is the variable being controlled/changed to see if there are any effects on the dependent variable (the thing getting tested/measured)
Hey there,
It means that, it is absorbed back into the blood after being filtered.
Hope this helps :))
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