I believe that a cell must use active transport to move molecules across the membrane against a gradient. Your answer should be D.
Proteins help in the development of muscle, acts in the immune
system and also as enzymes. They are considered as a <span>class of nitrogenous
organic compounds that are comprise of large molecules which contains one or
more long chains of amino acids and are a vital portion of all active
organisms.</span>
<span>The Cambrian. The Cambrian Explosion, which began roughly 545 million years ago, was a relatively rapid (~5-10 million years) diversification of multicellular life, including most of the animal phyla currently extant today. This was an evolutionary arms race of sorts, with many creatures achieving both larger size as well as symmetrical bodies and various structural supports, including skeletal systems. It was also a highly experimental times in terms of evolution, as many forms of creatures arose and went extinct in rapid succession during this period.</span>
Answer:
It contains thousands of nerve endings that make it an extremely sensitive organ. Touch stimulation of the nerve endings in the produces sensations of pleasure.
Explanation:
