Cells Chemicals Activities OCS Biology Mrs Bonifay Chemicals

Cells, Chemicals & Activities OCS Biology Mrs. Bonifay

Chemicals u u Living things are alike because: 1. they are composed of cells. 2. they have similar chemicals. These chemicals include: 1. water. 2. carbohydrates. 3. fats. 4. proteins. 5. minerals. 6. vitamins. 7. nutrients

WATER Life cannot exist without water. u Water makes up about 2/3’s of a cell’s weight. u Special properties of water allow it to break down things into tiny particles. u When water and these particles are evenly mixed, it is called a solution. u Your bodily fluids and liquids in your cells are not pure water; they are a solution of many salts, water, and other chemicals. u

CARBOHYDRATES u Carbohydrates are sugars and starches. u Living things use carbohydrates for energy. u Plants use the energy from sunlight to make carbohydrates from carbon dioxide and water. u Animals get energy from the carbohydrates made by plants.

FATS u Fats store large amounts of energy that are released when they are broken down. u Of all the chemicals important for life, fats contain the most energy.

PROTEINS u u Proteins also provide energy for living things. Proteins have other important functions: 1. They help to repair damaged cells and build new ones. 2. They help control body activities such as heart rate and breaking down food. Proteins are made up of smaller molecules called amino acids. There are 20 different amino acids that can be arranged in different ways to make different proteins. Proteins with different shapes have different functions.

MINERALS, VITAMINS, & NUTRIENTS u Minerals and vitamins are needed by living things in small amounts. u Nutrients are any chemicals found in foods that are needed by living things. u Nutrients include minerals and vitamins.

ACTIVITIES u u Getting food: 1. Animals get food by eating plants or other animals. 2. Plants make their own food. Digestion breaks down food into chemicals that cells can use. During respiration, cells release the energy that is stored in chemicals. The removal of wastes from living things is excretion.

MORE ACTIVITIES u u u Movement in plants and animals is outside and inside living things. Materials inside plants and animals are in constant motion. Animals and plants have tissues and organs that sense signals from their surroundings. Example: Many flowers open in the morning light and close when darkness comes. The ability of living things to keep their internal conditions is called homeostasis. An example of this is your body maintaining a “normal” temperature range around 98. 6 degrees. Another activity that living things do is growing. Development happens as living things grow.

Reproduction is the process by which living things produce offspring. u Different types of reproduction: 1. Bacteria reproduce by dividing in two. 2. In other living things (humans, for example), reproduction needs two parents. u Offspring of living things resemble their parent or parents. u