Chapter 1 Notes The Human Organism

Overview of Anatomy and Physiology the scientific discipline that investigates the body’s structure. Ex. Anatomy describes the shape and size of bones. Physiology the scientific investigation of the processes or functions of living things. LZHS McGraw-Hill

Types of Anatomy Gross Anatomy- structures examined without a microscope. Systemic- studied system by system. Regional- studied area by area. Surface- external form and relation to deeper structures as x-ray in anatomic imaging. Microscopic Anatomy- structures seen with a microscope. Cytology: cellular anatomy. Histology: study of tissues. LZHS McGraw-Hill

Topics of Physiology Reveals dynamic nature of living things. Considers operations of specific organ systems. Cell physiology- examines processes in cells Neurophysiology- focuses on the nervous system Pathology Exercise Physiology LZHS McGraw-Hill

Structural & Functional Organizations Chemical level Atoms Molecules Cell level Tissue level Organ level Organ system level Organism level LZHS McGraw-Hill

Terminology and the Body Plan Anatomical Position- body erect, face forward, feet together and palms face forward Other Body Positions Supine: lying face upward. Prone: lying face downward. LZHS McGraw-Hill

Directional Terms Superior- A structure above another. Inferior- A structure below another. Anterior- The front of the body. Posterior- The back of the body. Dorsal-Back area. Ventral-Stomach area. Proximal- Closer to the point of attachment to the body than another structure. Distal- Farther from the point of attachment to the body than another structure. Medial- Toward the midline of the body. Lateral- Away from the midline of the body. Superficial- Toward or on the surface. Deep- Away from the surface, internal. LZHS McGraw-Hill

Body Terms LZHS McGraw-Hill

LZHS McGraw-Hill

Characteristics of life Organization- condition in which there are specific relationships and functions. Metabolism- all chemical reactions of the body. Responsiveness- ability to sense changes and adjust. Growth Development- changes over time. Differentiation- change from general to specific. Morphogenesis- change in shape of tissues, organs. Reproduction- new cells or organisms. LZHS McGraw-Hill

CONCEPT CHECK! What is the difference between anatomy and physiology? -A: study of the structures & parts of an organism -P: study of the processes & functions What are the levels of organization of living things? Describe them. -cells, tissues, organs, organ systems, organisms What is metabolism? -all the chemical reactions in the body What is the difference between growth and development? -growth: increase in height or mass -development: changes over time (differentiation & morphogenesis) LZHS McGraw-Hill

Body Parts and Regions Upper limb- consists of the arm, forearm, wrist, & hand. Lower limb- consists of the thigh, leg, ankle, and foot. Central region of body- consists of the head, neck and trunk. Trunk: divided into the thorax (chest), abdomen, and pelvis. LZHS McGraw-Hill

Body Planes Sagittal plane- divides the body vertically into right & left portions Midsagittal/Median- divides the body into equal right and left halves. Parasagittal- runs vertically through the body to one side of the midline Transverse (Horizontal)- divides the body into superior & inferior portions. Frontal (Coronal)- divides the body into anterior and posterior parts. LZHS McGraw-Hill

LZHS McGraw-Hill

Body Cavities Thoracic Cavity- surrounded by the rib cage Mediastinum- contains the heart, thymus gland, trachea, esophagus, blood, & vessels. Diaphragm- large muscle that separates upper & lower cavities Abdominal Cavity Contains the stomach, intestines, liver, spleen, pancreas, and kidneys. Pelvic Cavity Contains the urinary bladder, part of the large intestines, and the internal reproductive organs. Ambdominopelvic- large double cavity below breathing muscle LZHS McGraw-Hill

Serous Membranes Serous membranes- covers the organs & lining of the trunk cavities. Visceral-thin membrane that covers the organs within the cavity. Parietal- wall of body cavity that covers its surface. Pericardial cavity- surrounds the heart Pleural cavity- surrounds each lung. LZHS McGraw-Hill

Systems of the Body Systems Studied  Integumentary-consists of skin, hair, nails & sweat glands Skeletal-protects/supports body, produces blood cells, & stores minerals (bones) Muscular-consists of muscles (movement) Nervous-consists of brain & spinal cord, nerves & receptors Vascular-blood Circulatory-consists of the heart and blood vessels Respiratory-exchanges gases btn the blood & air & regulates blood pH Digestive-breaks down food & absorbs nutrients Reproductive-ability to reproduce new offspring Not Studied…But still important to the body  Endocrine-consists of glands that secrete hormones Lymphatic-maintains tissue fluid balance & absorbs fat Urinary-removes waste products from the circulatory system & regulates blood pH LZHS McGraw-Hill

Homeostasis Values of variables fluctuate around the set point to establish a normal range of values. Set point- the ideal normal value of a variable. What is the set point for body temperature? LZHS McGraw-Hill

Negative Feedback Most systems of the body are regulated by negative-feedback mechanisms that maintain homeostasis. 3 Components Receptor: monitors the value of some variable (Ex. Blood Pressure) Control Center: establishes the set point around which the variable is maintained Effector: can change the value of the variable. LZHS McGraw-Hill

Negative Feedback LZHS McGraw-Hill

Positive Feedback When a deviation occurs, response is to make deviation greater. Leads away from homeostasis. Can result in death.  LZHS McGraw-Hill