You couldnt survive without your skin. It has many important functions. The main function of the skin is controlling what enters and leaves the body. It prevents the loss of too much water from the body. It also prevents bacteria and other microorganisms from entering the body. The skin helps maintain a constant body temperature. It keeps the body cool in two ways. Sweat from sweat glands in the skin evaporates to cool the body. Blood vessels in the skin dilate, or widen. This action increases blood flow to the body surface. This allows more heat to reach the surface. The heat is then able to radiate off the body. The opposite happens to retain body heat. Blood vessels in the skin constrict, or narrow. This decreases blood flow to the body surface. This reduces the amount of heat that reaches the surface. When this happens, less heat can be lost to the air.

Question: "What kind of vessels in the skin dilate to help cool the body?"

Answer: "Plastic vessels"

Response: no

Flowing water causes sediment to move. Flowing water can erode both rocks and soil. You have already learned that materials can dissolve in water. With enough time, even rocks can be dissolved by water. This process happens really slowly. It may take over a million years to dissolve a rock. It doesnt matter how big the rock is. With enough time, flowing water can dissolve it. Moving water also has the ability to move small pieces of rock and soil. How can water move a rock? Doesnt it need energy? Of course, water gets its energy because it is moving. Moving water has kinetic energy. Things that have more energy can do more work. When water stops moving it will have no energy. It will no longer be able to move the rock and soil. When this happens the rock and soil will settle to the bottom of the calm water. Scientists call this process deposition.

Question: "Does moving water have kinetic energy?"

Answer: "Yes"

Response: yes

Mary loved walking through the woods with her dog, Max. Max and Mary would go on all sorts of adventures together. They really loved looking for blueberries together and then falling asleep next to each other in the tall grass. One day, as Mary was picking the blueberries, she turned around to find that Max was not there. She became worried and ran off to look for her dog. She looked in all of their favorite spots...next to the stream, in their secret hiding place behind the raspberry bushes, and even inside the old cabin that sat in the woods. But poor Max was nowhere to be found. Nonetheless, Mary would not give up. She kept looking and she found him not very far away. He had seen a squirrel and run to chase it. When Mary called Max's name he left the squirrel and happily returned to Mary, wagging his tail as he went.

Question: "What things did Mary do?"

Answer: "Walking in the woods"

Response: yes

Do all plants live on the land? Some plants do live in the water. To do this, they have evolved special traits. Plants that live in water are called aquatic plants. Living in water has certain benefits. There is certainly plenty of water! The plant does not need special traits to absorb, transport, or conserve water. They do not need a large root system. They do not need a strong stem to hold up the plant. The plant uses the water for support. Dont think water plants have it easy, though. They also face challenges. Living in water isnt that easy. They do need some special traits to survive. It is tough for the plant to reproduce. Pollination by wind or animals cant happen under water. Sunlight cannot reach very far beneath the waters surface. Some aquatic plants have floating flowers and leaves.

Question: "How is an aquatic plant held up?"

Answer: "They use water for support"

Response:
yes