<span>Pepsin is an enzyme that breaks down proteins. Produced in the stomach, pepsin becomes inactive at pH values of 6.5 or more, but it is not fully denatured until it is in an environment with a pH of 8.0. Bile in the small intestine increases the pH value of food from the stomach to make them alkaline, which denatures pepsin.</span>
From my notes
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1.mature shark
2. eggs
3. pups
4. new born shark
5. immature shark
then it goes on and on
Answer: the answer is <u><em>A</em></u>
- Explanation: Because bears know that every time they go for food near the picnic <u>they will find some</u> there
1.)Coral reefs are busy underwater ecosystems. Some people call them the “rainforests of the sea.” The corals look like rocks but actually are animals. They have hard calcium carbonate skeletons like clams. They form a base for lots of other organisms to live. You’ll find crabs, sea stars, worms, clams, sponges, jellies, sea turtles, and lots of fish. Coral reefs are complicated and very fragile. They are easily affected by pollution.
2.) Tropical rainforests are near the equator where it’s almost always warm and wet. These are the key ingredients for making lots of lush plants and trees. Half of the world’s plants and animals live in tropical rainforests. It’s a very busy ecosystem with many kinds of plants, animals, fungi, and microscopic organisms. Many of them live here and nowhere else.
3.) In the world’s many deserts, there is very little rain. The land is very, very dry. Here, living things have creative ways of finding and saving water. Cactuses are very good at storing water. They can live without rain for months. The kangaroo mouse lives in the Nevada desert. It rarely drinks water. It can get its water from the food it eats.
The immune system protects the body from possibly harmful substances by recognizing and responding to antigens.
