There are a couple reasons the ice is important to polar bears, but given the choices you have the correct one would be:
A. The polar bears can’t out swim the seals, so they sit quietly on an ice platform and attack the seals when they come up for air.
<span>(4) active transport
</span>Active transport is the movement of molecules across a cell membrane in the direction against their concentration gradient, i.e. moving from an area of lower concentration to an area of higher concentration.
The savanna is very dry and desert like. Grasslands get precipitation and have tons of grass, hence the name grasslands.
Assessing aggregate exposure to a series of compounds with the same biological mechanism is called cumulative exposure assessment.
<h3>
What is cumulative exposure?</h3>
Because cumulative exposure evaluations evaluate exposure to numerous stressors via different pathways, they are referred to as "combined exposure assessments." Exposures to a single stressor are estimated using aggregate evaluations from different sources and pathways.
Cumulative evaluations portray real-world exposure more accurately, but they also provide an element of complexity not seen in typical exposure assessments , which evaluate stressors separately.
Learn more about cumulative exposure refer:
brainly.com/question/20749276
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Answer:
Many different genes control the height of the plants
hope this helps! <3