Human Anatomy and Physiology Ch 1 – Introducing the Human Body

Subdivisions of A and P Gross Anatomy Cytology Histology Embryology Pathology

Human Requirements for Life Water Food Oxygen Appropriate environmental temp. Appropriate environmental pressure Protection from radiation

Characteristics of Life 1.Movement; voluntary/involuntary 2.Metabolism; catabolism and anabolism 3.Growth 4.Responsiveness 5.Reproduction 6.Adaptations

Organization of the Human Body Chemical level; atoms – molecules – compounds Cellular level; blood cell, muscle cell Tissue level; epithelial, connective, muscle, and nervous Organ level Body system level Organism level

Human Body Systems pages 6-9 Integumentary Respiratory Skeletal Muscular Nervous Reproductive Endocrine Cardiovascular Lymphatic Digestive Urinary

Things that must be regulated in body: temp Pressure Fluid balance Blood pressure

Homeostatic Mechanisms 2 types 1. Intrinsic/autoregulation- 2. extrinisic Intrinsic Adjusts automatically w/in a cell, tissue or organ Ex.- decrease in O 2 levels leads to dilation of b.v. by chemicals in cell Extrinsic Nervous or endocrine system causes adjustment Exercising activates N.S. to increase heart rate and increase blood to muscles

Homeostatic Mechanism involves five parts: 1. stressor – env. Change 2. receptor- picks up stressor 3. regulator – aka “control center” 4. effector – responding body part 5. response

Ac kicking on thermostat thermometer Increase in temp Lower temp 72 degrees

Sweating Dilation of bl.v. Hypothalamus Receptors in hypothalamus Increase in temp Lower temp 98.6

insulin Beta cells of pancreas pancreas food.body cells to increase sugar uptake Normal bl.glucose levels

Types of Feedback Mechanisms Negative –Counteracts the stressor –Brings system back to steady state –Diagram resembles a figure “8” or a circle Positive –Works with the stressor to encourage the change –Only a few exist in the human body –Ex. Blood clotting p15, circ. shock p.721, childbirth p.1084

Oxytocin released fr. pituitary Uterus contracts Prostoglandins released Contractions increase Baby arrives!!! Stretching of cervix