Answer:
Active uptake (which I think you mean active transport) is important when the concentration gradient is against that of a certain substance, so it doesn't cross the membrane through diffusion or passive transport. It is sometimes necessary if a substance needs to move across a membrane but can't do so due to electrical charge or that there is a substance on the other side of the membrane preventing diffusion.
Explanation:
Answer: A (colored feathers.)
Explanation: There are many birds with colors that are variously different on the Galapagos.
So, Darwin carefully observed the finches of the Galapagos island. What he noticed was that they were similar to the mainland finches, but each island finch has different colored feathers.
The heads of phospholipids are hydrophilic while the tails are hydrophobic
Answer: what I learned is that natural selection needs 4 things
Explanation:
over production
genetic variation
i don’t remember the rest but those are the main ones so that there’s lots of offspring in case some cant survive
HOPE I HELPED
Answer:
It has increased
Explanation:
The concentration of carbon dioxide in the atmosphere has increased in the last 200 years. The extra carbon dioxide is causing an enhanced greenhouse effect greater than would happen naturally.