So, of course, many plants get the energy they need to grow from the sun. But what about inside caves? Not much sunlight in there, of course, however, we can see some plant life just inside the mouth of a cave, near the entrance, there's an area with an unusual name, an area known as the Twilight Zone. This part of the cave does get some sunlight. It's a limited amount, but it is enough light for some plants to grow. However, this little bit of light wouldn't be sufficient for the cave dwelling plants to convert enough energy to survive without some adaptations that enable them to do this. Let's talk about a couple. One adaptation these plants may have is a physical feature that allows them to take full advantage of the light that does reach them, even so weakly in The Twilight Zone, a feature that enables them to make the most of the limited light there and maximize it. The plants must be able to capture and absorb all the light possible in order to convert it into the energy they need to grow. For example, some of these plants have especially large leaves, leaves with a greater surface area so there are more cells in each leaf, more of the cells that can capture and absorb available light. Another adaptation these plants have is an ability to take advantage of light coming from only one direction, out in the open. Of course, most plants get sunlight from all directions, but for cave dwelling plants, the light that is available comes just from the cave entrance. So for example, within the cells of certain plants, there are what are called chloroplasts, which are responsible for absorbing light for the plant, and in these plants, the chloroplasts are all clustered, grouped together on the same side in each of the plant cells, the side that's toward the cave entrance, with the chloroplasts in each cell positioned toward The cave entrance, the plant is able to gather as much light as possible from that direction.