By P. Dawson. Washington & Jefferson College.

The initial symptoms of hypothermia are When the body’s heat-producing mechanisms cannot keep numbness order diabecon 60 caps, paleness generic diabecon 60 caps with visa, delirium, and uncontrolled shivering. A lengthy exposure temperature falls below 32° C (90° F), the heart loses its ability to to temperatures below 20° C (68° F) and dampness may lead to this pump blood and will go into fibrillation (erratic contractions). This is why it is so important that a hiker, for example, victim is not warmed, extreme drowsiness, coma, and death follow. Integumentary System © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 114 Unit 4 Support and Movement (a) (b) FIGURE 5. During the rainy season, which may last 5 to 6 months, the children are kept indoors. Rickets develops from an improper diet and also from lack of the sunlight needed to synthesize vitamin D. Called cuta- neous receptors, these sensory nerve cells are especially abun- Because of the effective protective barriers of the integument al- dant in the skin of the face and palms, the fingers, the soles of ready described, cutaneous absorption (absorption through the the feet, and the genitalia. Some gases, such as oxygen and carbon dioxide, back and on the back of the neck and are sparse in the skin over may pass through the skin and enter the blood. Generally speaking, the thinner the UV light, necessary for synthesis of vitamin D, are absorbed read- skin, the greater the sensitivity. Of clinical consideration is the fact that certain chemicals such as lipid-soluble toxins and pesticides can easily enter the body through the skin. Communication Humans are highly social animals, and the integument plays Synthesis an important role in communication. Various emotions, such The integumentary system synthesizes melanin and keratin, which as anger or embarrassment, may be reflected in changes of remain in the skin synthesis of vitamin D, which is used elsewhere skin color. The contraction of specific facial muscles pro- in the body and begins in the skin with activation of a precursor duces facial expressions that convey an array of emotions, in- molecule by UV light. The molecule is modified in the liver and cluding love, surprise, happiness, sadness, and despair. Only small amounts of UV light are necessary for vita- frequently elicit subconscious responses from others who de- min D synthesis, but these amounts are very important to a grow- tect them.

Along the superior border diabecon 60caps without prescription, a distinct depression called the scapu- Clavicle lar notch is a passageway for the suprascapular nerve order 60caps diabecon mastercard. Clinically, the pectoral girdle is significant be- joint away from the trunk to permit freedom of movement. The cause the clavicle and acromion of the scapula are frequently broken in trying to break a fall. The acromion is used as a landmark articulation of the medial sternal extremity (fig. This site is chosen icle to the manubrium of the sternum is referred to as the stern- because the musculature of the shoulder is quite thick and contains oclavicular joint. Both processes serve as attach- In strict anatomical usage, arm refers only to this portion of the ments for ligaments. The long, delicate clavicle is the most commonly broken bone in the body. When a person receives a blow to the shoulder, or Humerus attempts to break a fall with an outstretched hand, the force is trans- mitted to the clavicle, possibly causing it to fracture. It consists of a proximal head, which articulates with the gle- the conoid tubercle. Because the clavicle is directly beneath the skin and is not covered with muscle, a fracture can easily be palpated, noid cavity of the scapula; a body (“shaft”); and a distal and frequently seen. Skeletal System: The © The McGraw−Hill Anatomy, Sixth Edition Appendicular Skeleton Companies, 2001 174 Unit 4 Support and Movement Parietal bone Frontal bone Temporal bone Skull Occipital Zygomatic bone bone Maxilla Mandible Clavicle Pectoral Scapula girdle Costal cartilages Sternum Rib cage Ribs Humerus Vertebral column Ulna Ilium Pelvic girdle Os Pubis Sacrum coxae Coccyx Ischium Radius Carpal bones Metacarpal bones Phalanges Femur Patella Tibia Fibula Calcaneus Tarsal bones Creek Metatarsal bones Phalanges (a) (b) FIGURE 7. Skeletal System: The © The McGraw−Hill Anatomy, Sixth Edition Appendicular Skeleton Companies, 2001 Chapter 7 Skeletal System: The Appendicular Skeleton 175 Acromion of scapula Clavicle Coracoid process of scapula Head of humerus Scapula Acromial extremity Sternal extremity Greater tubercle Conoid of humerus tubercle Body of humerus (a) Creek Body of Acromial extremity clavicle Sternal extremity FIGURE 7. Skeletal System: The © The McGraw−Hill Anatomy, Sixth Edition Appendicular Skeleton Companies, 2001 176 Unit 4 Support and Movement Greater tubercle Greater tubercle Lesser tubercle Head Anatomical neck Intertubercular groove Surgical neck Nutrient foramen Deltoid tuberosity Body of humerus (posterior surface) Body of humerus (anterior surface) Olecranon fossa Radial fossa Coronoid fossa Lateral epicondyle Medial epicondyle Lateral epicondyle Capitulum Ulnar sulcus Trochlea (a) (b) FIGURE 7. Surrounding the margin of the head is a slightly in- the lateral rounded part that articulates with the radius. The greater tubercle is a large knob on the lateral proximal the lateral and medial epicondyles.