Phospholipids have two distinct polarities. The phosphate head is always polar, while the two "tails" it has are nonpolar.
Advancement in technology. For example, body odor on humans was considered attractive thousands of years ago. Now it's just considered a hassle and we try our best to get rid of the smell.
Biology answers many questions<span>, </span>but its main focus is<span> how living organisms interact and function.
hope it helped give thanks :)
</span>