Learning Goal 2 Explain the function of structures involved in protection, support, and movement of animals Protection Epithelial Tissue – Classifications of Epithelial Tissue – Support Skeletal Systems – Movement Muscle Tissue – Muscle Cells – Skeletal Muscle – Cardiac Muscle – Smooth Muscle – Patterns of Movement in Vertebrates Fishes – Amphibians and Reptiles – Birds and Mammals -

LG 2 Terms 1.Epithelial Tissue – 2.Hydrostatic Skeleton – 3.Exoskeleton – 4.Endoskeleton – 5.Skeletal Muscle – 6.Cardiac Muscle – 7.Smooth Muscle – 8.Actin – 9.Myosin – 10.Sarcomere –

Unit III Anatomy and Physiology of Animals Learning Goal 2 Explain the function of structures involved in protection, support, and movement in animals

Protection Epithelial Tissues Cover body surfaces and the surfaces of internal organs, as well as line cavities and ducts within the animal body. They provide protection from invasion by bacteria and viruses and secrete and absorb substances.

Classifications of Epithelial Tissue: Simple or stratified, meaning single or multi- layered. Squamous – flattened cells Cuboidal – roughly shaped like cubes Columnar - elongated

Support Skeletal Systems Hydrostatic Skeletons- consist of muscles and fluid that provide support for the animal with no rigid support from tissue like bone. Found in many invertebrates like worms, and cnidarians.

Exoskeletons A rigid external body covering that provides support and protection. May be made of hard calcium carbonate such as in mollusks or chitin as in arthropods.

Endoskeletons Consist of internal body structures made of bone or cartilage and protection in some invertebrates and all vertebrates.

Movement Muscle tissue provides all animals with the ability to move around independently. Muscle cells can contract or shorten due to the interaction of two proteins, actin and myosin. The contractile unit of a muscle cell is called a sarcomere. There are three types of muscle tissue, skeletal, cardiac, and smooth which produce movement in vertebrates.

Skeletal Muscle Also called muscle fibers, are attached by tendons to the skeleton. They contain many nuclei and are packed with actin and myosin molecules.

Cardiac Muscle This is the contractile tissue of the heart. It has a striated appearance because it contains actin and myosin molecules arranged in a similar manner to skeletal muscle. They form an interlinked network that makes heart muscle contract in all directions, producing a squeezing or pumping action.

Smooth Muscle Found in the walls and tubes of cavities in the body. Contractions of smooth muscle move and mix the stomach and intestinal contents, constrict blood vessels, and push the infant out of the uterus during childbirth.

Patterns of Movement in Vertebrates Fishes have muscle blocks located on either side of backbone that give them a side-to-side movement for forward motion.

Amphibians and reptiles have limbs on sides in a “push-up position” causing them to walk in a side-to-side motion.

Mammals have limbs straight under them giving them more of an up and down motion when they walk.

LG 2 Terms 1.Epithelial – 2.Hydrostatic Skeleton – 3.Exoskeleton – 4.Endoskeleton – 5.Actin – 6.Myosin – 7.Sarcomere – 8.Skeletal Muscle – 9.Cardiac Muscle – 10.Smooth Muscle –