1. Brian Howey is a conformist.

2. I. Skin A.Anatomy 1. 3 Layers: Epidermis, Dermis and Subcutaneous/Hypodermis (not part of skin). 2. Melanocytes: Cells within the dermis that produce melanin. 3. Keratinocytes: Cells within the dermis that produce keratin, the major protein in skin

3. I. Skin B. Physiology 1. Makes vitamin D 2. Protection: Strong due to collogen component. 3. Temperature Regulation

5. II. Bone A.Osteocytes: Bone cells 1. Osteoblasts: Build Bone Tissue 2. Osteoclasts: Dissolve Bone Tissue B. Osteon: Functional Unit of Bone Building.

7. II. Bone C. Anatomy: Compact bone, Spongy bone, Yellow Marrow, Red Marrow 1. Compact: Lacks air spaces 2. Spongy: Interlaced with air spaces 3. Yellow Marrow: Stores fat 4. Red Marrow: Produces blood cells.

8. III. Muscle Contraction A.Sarcomere: Functional unit of muscle contraction. 1. Actin – Thin protein filaments 2. Myosin - Thicker protein filament

9. Fig. 38.20c, p. 658 one actin molecule part of a thin filament Arrangement of actin molecules in the thin filaments of a sarcomere parts of myosin molecule part of a thick filament Arrangement of myosin molecules in the thick filaments of a sarcomere

10. Muscle Contraction B. Sliding Filament Theory: The myosin proteins slide past the actin filaments. Pulls Z-bands closer together.

11. Fig. 38.21, p. 659 Cross-bridge forms between an actin and a myosin filament Actin filament slides past myosin filament, toward sarcomere’s center, in a power stroke The cross bridge is broken Another cross- bridge forms between same filaments Another power stroke slides actin filament closer to the center of sarcomere between contractions actinmyosinactin same sarcomere contracted

12. IV. Signaling Muscle Contraction A.Motor neurons stimulate release of calcium for muscle contraction. B.Calcium provided by Sarcoplasmic Reticulum.

13. C. Acetylcholine is neurotransmitter that communicates with muscle.

14. Fig. 38.23, p. 660,61 section from spinal chord motor neuron Signal from the neuron system travel along spinal cord, down motor neuron T tubule section from a skeletal muscle Sarcoplasmic reticulum (calcium storage) plasma membrane of skeletal muscle cell Z band one of the myofibrils inside the muscle cell

15. IV. Fueling Muscle Contraction A. When myosin and actin interact, they need ATP to release. B. Preference for ATP: Creatine Phosphate, Respiration, then Lactic Acid Fermentation