Difference between high school biology and college biology

There is more to remember yes. But as you go into higher levels of biology, the focus is usually going to shift more towards molecular biology. Also the content is going to get more detailed and specific, knowing specific names of receptors, etc.

since there are no options posted i'll give you a few examples.

a dolphin's flipper, bird's wing, cat's leg.

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added