Organization Of The Human Body Maintaining Homeostasis

Definition of Anatomy & Physiology AnatomyAnatomy –Structures –Relationship of structures Tortora Page: 2

Definition of Anatomy & Physiology PhysiologyPhysiology –Function of structures Tortora Page: 2

William HarveyWilliam Harvey – –First to observe heart and circulation. –First to notice differences between warm and cold blooded animals. William Harvey First “Real” Anatomist

Levels of Structural Organization ChemicalChemical CellularCellular TissueTissue OrganOrgan Organ systemOrgan system OrganismOrganism Tortora Page: 2

Integration of Body Systems 10 organ systems10 organ systems IntegratedIntegrated Strength of systems.Strength of systems. –Specialization therefore efficiency Weakness of systems.Weakness of systems. –interdependence Tortora Page: 2-4

Unifying Processes of Life MetabolismMetabolism –Catabolism Vs Anabolism ResponsivenessResponsiveness MovementMovement GrowthGrowth –# of cells, cell size, space around cells. DifferentiationDifferentiation ReproductionReproduction –Cells –Organism Tortora Page: 5

Maintaining An Internal Balance HomeostasisHomeostasis Range of tolerance.Range of tolerance. Optimal conditionsOptimal conditions Tortora Page: 5-7

Role of Stress & Homeostasis Homeostasis.Homeostasis. –Maintaining an internal balance. Role of stress.Role of stress. –Environmental factor that could alter the balance. Tortora Page: 5-7

Homeostasis and Blood Pressure Blood pressure is force behind blood as it flows through arteries.Blood pressure is force behind blood as it flows through arteries. Systolic Vs Diastolic pressureSystolic Vs Diastolic pressure Increase heart rate and stroke volume increase BP.Increase heart rate and stroke volume increase BP. Tortora Page: 5-7

Homeostasis and Blood Pressure Pressure sensitive nerves in arteries sense higher BP.Pressure sensitive nerves in arteries sense higher BP. Nerves send signal to brain.Nerves send signal to brain. Brain sends signals to slow heart rate.Brain sends signals to slow heart rate. Tortora Page: 5-7

Feedback Systems Feedback systems are either negative or positive.Feedback systems are either negative or positive. –Negative feedback systems correct deviations due to stress. –Positive accentuate the action. –Most feedback systems in the human body are negative. –Positive feedback mechanisms are regulated by negative feedback loops. Tortora Page: 6

Regulation of Glucose Levels The glucose roller coaster: The glucose roller coaster: –Low levels after sleep. –High levels after 3 donuts and hot chocolate for breakfast! –Low levels by lunch. –High levels after lunch of hershey candy and pepsi ! –Low levels by 2:00 Page 327 Tortora

Regulation of Glucose Levels Excess glucose:Excess glucose: Insulin is secreted by islets of Langerhans (beta cells) in pancreas.Insulin is secreted by islets of Langerhans (beta cells) in pancreas. –Absorbed by liver cells which converts glucose to glycogen. (polysaccharide) –Causes cells to take in glucose Page 327 Tortora

Regulation of Glucose Levels When blood glucose levels are low:When blood glucose levels are low: –Glucagon is secreted by alpha cells in pancreas –Glycogen is broken down into glucose and released into blood. –Glucose levels surrounding the cells stays fairly even through out the day. Page 327 Tortora

Basic Anatomical Position 1.Individual is standing upright. 2.Arms placed at sides of the body. 3.Palms facing forward. 4.Feet flat on floor, toes forward. Tortora Page: 7-15

Directional Terms Used to locate various body structures in relationship to each other.Used to locate various body structures in relationship to each other. –Superior Vs Inferior (Cranial Vs Caudal) –Anterior Vs Posterior ((Ventral Vs Dorsal) –Medial Vs Lateral –Intermediate –Proximal Vs Distal –Superficial Vs Deep Taken from Exibit 1.2 Tortora Page: 2

Planes & Sections Imaginary flat surfaces through the body.Imaginary flat surfaces through the body. –Sagittal plane MidsagittalMidsagittal ParasagitalParasagital –Frontal plane –Transverse Tortora Page: 7-15

Body Cavities Spaces within the body that contain organs.Spaces within the body that contain organs. Ventral body cavityVentral body cavity –Thoracic (heart& lungs) Pericaridal cavityPericaridal cavity Pleural cavityPleural cavity –Abdominal (digestive, liver, reproductive) Lining of cavity is called the peritoneumLining of cavity is called the peritoneum Tortora Page: 7-15

Body Cavities Dorsal CavityDorsal Cavity –Cranial cavity Brain –Spinal cavity Spinal cord Tortora Page: 7-15