Anatomy & Physiology Unit 1 – Introduction

Anatomy & Physiology Anatomy Gross Anatomy Microscopic Anatomy Study of structure & parts Gross Anatomy Large, easily observable structures Microscopic Anatomy Only viewable by microscope Physiology Study of function and how parts work

Molecules Atoms Chemical level Atoms combine to form molecules

Smooth muscle cell Molecules Atoms Cellular level Cells are made up of molecules Chemical level Atoms combine to form molecules

Smooth muscle cell Molecules Atoms Smooth muscle tissue Cellular level Cells are made up of molecules Tissue level Tissues consist of similar types of cells Chemical level Atoms combine to form molecules

Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Connective tissue Blood vessel (organ) Cellular level Cells are made up of molecules Tissue level Tissues consist of similar types of cells Organ level Organs are made up of different types of tissues Chemical level Atoms combine to form molecules

Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Connective tissue Blood vessel (organ) Cardio- vascular system Cellular level Cells are made up of molecules Tissue level Tissues consist of similar types of cells Organ level Organs are made up of different types of tissues Organ system level Organ systems consist of different organs that work together closely Chemical level Atoms combine to form molecules

Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Connective tissue Blood vessel (organ) Cardio- vascular system Cellular level Cells are made up of molecules Tissue level Tissues consist of similar types of cells Organ level Organs are made up of different types of tissues Organ system level Organ systems consist of different organs that work together closely Organismal level Human organisms are made up of many organ systems Chemical level Atoms combine to form molecules

Organ Systems Integumentary Skeletal Muscular Nervous Endocrine Cardiovascular Respiratory Digestive Urinary Lymphatic Reproductive

Integumentary system Skeletal system Muscular system Cardiovascular system Lymphatic system Nervous system

Male Reproductive system Female Reproductive system Digestive system Respiratory system Urinary system Endocrine system Male Female

Integumentary System Forms the external body covering Protects deeper tissue from injury Helps regulate body temperature Location of cutaneous nerve receptors

Skeletal System Protects and supports body organs Provides muscle attachment for movement Site of blood cell formation Stores minerals

Muscular System Produces movement Maintains posture Produces heat

Nervous System Fast-acting control system Responds to internal and external change Activates muscles and glands

Endocrine System Secretes regulatory hormones Growth Reproduction Metabolism

Cardiovascular System Transports materials in body via blood pumped by heart Oxygen Carbon dioxide Nutrients Wastes

Respiratory Keeps blood supplied with oxygen Removes CO2

Digestive System Breaks down food Allows for nutrient absorption into blood Eliminates indigestible material

Urinary System Eliminates nitrogenous wastes Maintains acid-base balance Regulates water and electrolytes

Lymphatic System Returns fluids to blood vessels Cleanses the blood Involved in immunity

Reproductive System Produces offspring

Characteristics of Life

Characteristics of Life Movement Maintain boundaries Response (reaction to change) Growth (in size, not shape) Reproduction (new organisms & cells) Respiration Digestion Absorption Circulation Assimilation (changing absorbed substances into different forms) Excretion (removal of metabolic wastes)

Requirements of Organisms

Requirements of Organisms Water Food Oxygen Heat Pressure (breathing, circulation)

Homeostasis Dynamic equilibrium Maintenance of a stable internal environment 3 parts: Receptor – receives info; detects stimuli Control center – determines set point & response Effector – provides means for response to stimulus

Variable (in homeostasis)

Variable (in homeostasis) Stimulus: Produces change in variable Imbalance Variable (in homeostasis) Imbalance

Variable (in homeostasis) Receptor (sensor) Change detected by receptor Stimulus: Produces change in variable Imbalance Variable (in homeostasis) Imbalance

Variable (in homeostasis) Input: Information sent along afferent pathway to Control center Receptor (sensor) Change detected by receptor Stimulus: Produces change in variable Imbalance Variable (in homeostasis) Imbalance

Variable (in homeostasis) Input: Information sent along afferent pathway to Control center Output: Information sent along efferent pathway to activate Receptor (sensor) Effector Change detected by receptor Stimulus: Produces change in variable Imbalance Variable (in homeostasis) Imbalance

Variable (in homeostasis) Input: Information sent along afferent pathway to Control center Output: Information sent along efferent pathway to activate Receptor (sensor) Effector Change detected by receptor Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis Stimulus: Produces change in variable Imbalance Variable (in homeostasis) Imbalance

Stimulus (Change occurs in internal environment.) Response (Change is corrected.) Receptors Effectors (muscles or glands) Control center (set point) (Change is compared to the set point.) Afferent Pathway Efferent Pathway

Receptors Thermoreceptors send signals to the control center. too high Normal body Temperature 37°C (98.6°F) Control center The hypothalamus detects the deviation from the set point and signals effector organs. Stimulus Body temperature rises above normal. Effectors Skin blood vessels dilate and sweat glands secrete. Response Body heat is lost to surroundings, temperature drops toward normal. too low Normal body temperature 37°C (98.6°F) Control center The hypothalamus detects the deviation from the set point and signals effector organs. If body temperature continues to drop, control center signals muscles to contract involuntarily. Receptors Thermoreceptors send signals to the control center. Effectors Skin blood vessels constrict and sweat glands remain inactive. Stimulus Body temperature drops below normal. Muscle Activity Generates body heat. Response Body heat is conserved, temperature rises toward normal.

Homeostatic Mechanisms Negative feedback (most common) Prevent sudden changes Shuts off original stimulus or reduces it Positive feedback Increases or adds to the change Produces more instability & chaos Blood clotting; child birth

Anatomical Terminology Anatomical position Standing erect Facing forward Upper limbs at the sides Palms facing forward and thumbs out

Terminology Universal system, used for: Position Direction Specific regions or structures

Directional Terms Superior (also: cranial or cephalad) Above; toward head or upper part of structure/body Inferior (also: caudal) Below; away from head or toward lower part of structure/body Ventral (also: anterior) In front of; at/toward front of body

Directional Terms (continued) Dorsal (also: posterior) Behind; toward backside of body Medial On the inner side of; toward or at midline of body Lateral On the outer side of; away from midline of body Proximal Closer to origin of the body part (or point of attachment of a limb to the body trunk) Used for the extremities

Directional Terms (continued again) Distal Farther from origin of body part (or point of attachment of a limb to the body trunk) Used for the extremities Superficial (also: external) Toward or at the body surface Deep (also: internal) More internal; away from body surface Ipsilateral – same side Contralateral – opposite side

Anterior ( V entral) Posterior (Dorsal) Superior Inferior Medial Lateral Midline Right Left Proximal Distal

Regional Terms/Body Landmarks

Body Planes & Sections Sagittal section – divides into left & right parts Median (or midsagittal) section – divides into equal left & right parts Frontal (or coronal) section – divides into anterior & posterior parts Transverse (or horizontal, or cross) section – divides into superior & inferior parts

Sagittal (Midsagittal) Transverse Coronal

A section along a frontal plane A section along a transverse A section along the median plane Transverse (horizontal) Frontal (coronal) Parasagittal Median (midsagittal)

Other Body Sections Cross Section Oblique section Longitudinal section

Body Cavities 2 layers: Visceral layer – covers an organ Parietal layer – lines a cavity or body wall Thoracic Membranes Visceral pleura Parietal pleura Visceral pericardium Parietal pericardium Abdominopelvic Membranes Parietal peritoneum Visceral peritoneum Parietal perineum Visceral perineum

Body Cavities Dorsal Ventral Cranial cavity – houses brain Vertebral cavity – houses spinal cord Ventral Thoracic cavity – heart, lungs Abdominopelvic – digestive, urinary system organs

Body Cavities Cranial cavity Vertebral canal Thoracic cavity Diaphragm Abdominopelvic cavity Abdominal Diaphragm Pelvic cavity Cranial cavity Vertebral canal Body Cavities

Thoracic cavity Abdominopelvic cavity Abdominal Pelvic cavity Right pleural Mediastinum Left pleural cavity Pericardial Diaphragm Vertebral canal Cranial cavity Thoracic

Cranial cavity Frontal sinuses Sphenoidal sinus Orbital cavities Middle ear cavity Nasal cavity Oral cavity

Regions of the Body Abdominopelvic Quadrants

Abdominopelvic Regions (more specific) Right hypochondriac region lumbar iliac Epigastric Umbilical Hypogastric Left