LG 1 – Protection, Support, and Movement Plants Protection – Support – Invertebrates Support and Movement – Vertebrates Movement – Movement Patterns –

Unit II Organs and Organ Systems Learning Goal One Examine tissues in plants and animals that function in protection, support, and movement.

Plants Protection Dermal tissue is the outermost layer of cells that form the “skin” of the plant. Consists of epidermal cells covered by a waxy layer called a cuticle. The cuticle protects against water loss and injury.

Support Plant cells have cell walls made of the carbohydrate cellulose; otherwise known as fiber. Turgor Pressure Cells in stems have thick cell walls that when filled with water become very rigid helping the plant to stand upright.

Invertebrates (animals with no spinal cord) Protection A layer of cells known as epidermis protects from injury and water loss.

Support and movement Hydrostatic skeletons – muscles relax and contract, pushing against fluid filled cavity to change shape. Example: jellyfish, sea anemones

Exoskeletons – hard body covering made of chitin ( a type of carbohydrate). Movement is by muscles attached to exoskeleton. Example: insects, snails, clams, lobsters.

Endoskeletons – structural support located inside the body Endoskeletons – structural support located inside the body. Example: starfish

Vertebrates Protection – outer layer of epidermis and inner layer of dermis. Support – most have an internal skeleton of bone or cartilage.

Movement – ligaments connect bones and tendons connect muscle to bone.

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