The answer is b
<span>1.Upper Epidermis – The upper surface of a leaf that protects the inner cells of the leaf. 2.Palisade Layer – Long, thin, tightly-packed cells where most photosynthesis takes place. 3. Spongy Layer – Loosely packed cells with many air spaces between them in order to allow carbon dioxide to pass among the cells and get to the chloroplasts. 4. Lower Epidermis – The bottom layer that protects the underside of the leaf and has many openings (stomata)</span>
Answer:
When the molecules are too large.
Explanation:
Facilitated diffusion refers to the passive transport of substances down the concentration gradient via specific transport proteins present in the membrane. The large, polar, charged substances and ions cannot pass through the small spaces present between hydrophobic tails of membrane phospholipids. The transport proteins transport these substances in energy independent manner.
All cells require ATP for energy.
Answer:
An endangered species is an animal species that is in danger of becoming extinct, or dying out. An example of an endangered species would be tigers or sea turtles.
Explanation:
