Anatomy & Physiology Chapter 1

A & P Anatomy - study of structure Anatomy - study of structure Physiology - study of function Physiology - study of function Structure is always related to function Structure is always related to function

Levels of Organization Atom Atom Chemical Chemical –Molecule –Macromolecules –Organelle Cellular Cellular Tissue Tissue Organ Organ Organ System Organ System Organism Organism

Characteristics of Life = Metabolism Movement: internal or gross Responsiveness : rxn to internal or external change Growth: increase in size w/o change in shape Reproduction: new organisms or new cells Respiration: use of O 2 ; removal of CO 2 Digestion: breakdown of food into simpler forms Absorption: movement of substances through membranes & into fluids Circulation: movement within body fluids Assimilation: changing nutrients into chemically different forms Excretion: removal of metabolic wastes

Organism Requirements Water: required for metabolic rxns, transport of substances, temperature regulation Food: nutrients needed to supply energy & raw materials for building new living matter Oxygen: releases energy from nutrients Heat: byproduct of metabolism; rate of rxns Pressure: force that facilitates movement of air or fluids (atmospheric & hydrostatic)

Homeostasis condition in which the body’s internal environment remains within certain physiological limits condition in which the body’s internal environment remains within certain physiological limits –Ex: Temperature 98.6°F Receptors Receptors Set Point Set Point Effectors Effectors Feedback Loop Feedback Loop –Negative –Positive

Negative Feedback Loop – change from a set point is detected & the body acts to return to the set point Ex. Temp 98.6°F or 37°C

Positive feedback is a self-amplifying cycle in which a physiological change leads to even greater change in the same direction. Ex. oxytocin is secreted in small amounts at the beginning of labor. These small amounts cause more &more oxytocin to be released, causing uterine contractions throughout labor. Only when the baby is expelled does the feedback system shut down.

Anatomical Position The subject stands erect facing the observer, with feet flat on the floor, arms at sides & palms turned forward

Relative Positions (1) add to your list Supine = on back Prone = on belly

Relative Positions (2) Superior – Superior – –Toward the head or upper part of a structure Inferior – Inferior – –Away from the head or lower part of a structure

Relative Positions (3) Anterior Anterior –Nearer to or at the front of the body Posterior Posterior - Nearer to or at the back of the body

Relative Positions (4) Medial Medial –Nearer to the midline Lateral Lateral –Towards the sides /farther from the midline Intermediate Intermediate –Between two structures

Relative Positions (5) Proximal Proximal –Nearer to the attachment of a limb to the trunk, towards the point of origin Distal Distal –Farther from the attachment of a limb to the trunk, away from the point of origin

Relative Positions (6) Superficial Superficial –Toward the surface of the body Deep Deep –Away from the surface of the body

Relative Positions (7) add these Ipsilateral Ipsilateral –On the same side of the body Contralateral Contralateral –On the opposite side of the body

Human / Cat Clarifications Anterior = front, Ventral = belly Anterior = front, Ventral = belly –mean the same in humans but in the cat anterior is forward and ventral faces the ground Posterior = rear/behind, Dorsal = back Posterior = rear/behind, Dorsal = back –mean the same in humans but in the cat posterior is rear and dorsal faces up Cranial = toward the head Cranial = toward the head –which is Superior in humans, but superior is dorsal in cats Caudal = towards the tail Caudal = towards the tail –which is Inferior in humans, but inferior is ventral in cats

Directional Terms Review

Planes/Body Sections (1) Plane: an imaginary flat surface

Planes/Body Sections (2) Sagittal - Vertical plane dividing the body/organ into left & right halves Sagittal - Vertical plane dividing the body/organ into left & right halves –Midsagittal – Median/midline, equal sides –Parasagittal - Unequal sides

Planes/Body Sections (3) Transverse - Cross sectional or horizontal plane dividing the body/organ into superior (top) and inferior (bottom) portions Transverse - Cross sectional or horizontal plane dividing the body/organ into superior (top) and inferior (bottom) portions

Planes/Body Sections (4) Coronal/ Frontal - Divides the body/organ into anterior (front) & posterior (back) portions Coronal/ Frontal - Divides the body/organ into anterior (front) & posterior (back) portions

Planes/Body Sections (5) add this Oblique - Passes through the body/organ at an angle between transverse & sagittal or frontal planes Oblique - Passes through the body/organ at an angle between transverse & sagittal or frontal planes

Body Cavities (1) Confined spaces containing internal organs Confined spaces containing internal organs –protect, separate & support the organs 2 Main Cavities 2 Main Cavities –Dorsal & Ventral Each are divided in to smaller cavities Each are divided in to smaller cavities Viscera = organs within these cavities Viscera = organs within these cavities

Body Cavities (2) Dorsal - back Dorsal - back –Cranial - the cranial bones & the brain –Spinal (Vertebral Canal) – located inside the vertebral column & contains the spinal cord

Body Cavities (3) Ventral - front Ventral - front –Thoracic - Superior portion, heart & lungs Pleural - 2, surround the lungs, fluid filled Pleural - 2, surround the lungs, fluid filled Mediastinum - everything except the lungs Mediastinum - everything except the lungs –Pericardial - covers the heart –Abdominopelvic - Inferior portion Abdominal - Superior portion Abdominal - Superior portion –liver, spleen, stomach etc. Pelvic - Inferior portion Pelvic - Inferior portion –Urinary bladder, reproductive organs, lower intestines etc.

Membranes Serous membranes – thin slippery tissue lining the walls of the ventral cavity double layered Serous membranes – thin slippery tissue lining the walls of the ventral cavity double layered –Visceral layer – lines the organs –Parietal layer – outer membrane Pericardium – serous membrane around the heart Pericardium – serous membrane around the heart Pleural membrane - surrounds lungs Pleural membrane - surrounds lungs Peritoneum –lines the abdominopelvic cavity Mesentery – holds visceral organs of abdominopelvic cavity in place Peritoneum –lines the abdominopelvic cavity Mesentery – holds visceral organs of abdominopelvic cavity in place

Serous Membranes 1-14

The efforts of all systems must be coordinated for the animal to survive. Any organism is a coordinated living whole greater than the sum of its parts.

Major Body Systems Integument – body covering Integument – body covering Skeletal – support & movement Skeletal – support & movement Muscular – support & movement Muscular – support & movement Nervous – integration & coordination Nervous – integration & coordination Endocrine – integration & coordination Endocrine – integration & coordination Digestive– absorption & excretion Digestive– absorption & excretion Respiratory - absorption & excretion Respiratory - absorption & excretion Circulatory - transport Circulatory - transport Lymphatic/Immune – transport & immunity Lymphatic/Immune – transport & immunity Urinary - absorption & excretion Urinary - absorption & excretion Reproductive - reproduction Reproductive - reproduction

Abdominal Cavity Abdominal CavityRUQLUQRLQLLQ Quadrants Nine regions