Chapter 19, Lesson 4 How Animals Get and Digest Food

Filter Feeding Animals that live in water get their food by filtering or straining it. Protists and Bacteria from the water pass through their bodies. Sponges can not move around as adults, and filter feeding allows them to gather food without chasing it. Barnacles also remain in place and collect particles with their legs.

Feeding on Fluids Some animals get their food for the fluids in plants and other animals. Aphids and Cicadas are insects that have piercing mouthparts and they draw sap from roots, leaves, and stems. Bees, butterflies, and hummingbirds draw nectar from flowers. Spiders and assassin bugs capture insects and sucks the fluid from their bodies. Leeches, mosquitoes,and horseflies feed on the blood of vertebrates, including humans.

Consuming Large Pieces of Food Most animals consume or eat large pieces of solid food Animals use different kinds of body structures to capture and consume their food. Some animals break down their food before consuming and some eat it whole. Vertebrates are the only animals that have teeth. Each kind of tooth does a certain job. Chisel-like teeth cut food into pieces, sharp pointed teeth tear the flesh, flat surface teeth are used for gridding plants.

Digesting Food Food usually contains fats, proteins, and carbohydrates. These are the chemicals that an animal needs to get energy. The process of breaking down food into small chemicals is digestion. Digestion happens by the animal secreting digestive enzymes which speeds up the chemical change. Most animals digest their food outside of cells. So this allows them to eat much larger food.

Gastrovascular Cavities Gastrovascular cavities are were cnidarians digest food. Gastrovascular cavity is a hollow space where this process happens. Food enters through the mouth and special cells line the cavity. The cells secrete digestive enzymes which break down the food into smaller particles. Once it is broken down the cells are able to absorb the particles the material that is not able to be digested passes out through the mouth

Digestive Tracts Animals that are more developed have digestive tract. Example Humans The digestive tract is a tubelike digestive space with an opening at each end. Food moves through a digestive tract in one direction Food enters the mouth down the esophagus to the crop where it is stored. It then mixes in the stomach with the digestive enzymes and moves to the gizzard where it is turned into a watery paste. More digestive enzymes are added in the intestine. The walls of the intestine absorb the small chemicals while the material that is not used is passed thru the body. Some animals have little differences but for the most part this is how a digestive tract functions

Vocabulary Filter Feeding: A way of getting food by straining it out of the water. Secrete: Form and release or give off Enzyme: A substance that speeds up chemical change Gastrovascular Cavity: a digestive space with a single opening Digestive Tract: A tubelike space with an opening at each end.

**Vocabulary Quiz November 6th** Book Work: Page 455 Q 1-5 Workbook Activity # 74 **Vocabulary Quiz November 6th**