Chapter 1:

Introduction to the Human Body

The skull and vertebral column is part of the axial skeleton.The cerebral cortex consists of 4 lobes: frontal , parietal, temporal, occipitalSkeletal muscles pull on bones, creating forces that produce body motionThe stomach, small intestine, and large intestine are chambers of the digestive tract.

Anatomy or physiology

Anatomy or physiology?

Receptors of the eye and ear detect environmental changes for the respective senses of vision and hearing.Antidiuretic hormone, secreted from the posterior lobe of the pituitary gland, stimulates water reabsorbtion in the kidney.

Anatomy and Physiology

Anatomy – Study of structure or morphology of the body.

PhysiologyThe study of how the body works or functionsPathophysiology – how a body part functions when a person has a disease

II. Levels of Organization

From simple to complex

Atom molecule Large molecules Cells – basic unit of life Tissues – groups of

specialized cells Organs – has a specific

function Organ systems – groups

of organs Human organism

III. Organs and Organ systems

Major organ systems

Integument System

Skin, hair and nailsProtectionRegulate body temperatureSense of touch

Skeletal System

Bones, joints, cartilageProtects and supports body organs

Muscular System

Responsible for movement of skeletonposture

Nervous System

Brain, spinal cord, nerves, sense organsIntegration and coordinationRegulation and response

Endocrine System

GlandsSecrete hormones and chemicals to regulate body activities

                                                                                           

Circulatory System

Heart and blood vesselsTransports blood

Lymphatic System

Lymph nodesDefend the bodyimmunity

Respiratory System

LungsExchange of gases with the environment

                                                

    

Digestive System

Convert food to nutrientsAbsorb nutrientsEliminate waste

Urinary System

KidneysExcrete wasteFormation of urine

Reproductive System

Enable the human to reproduce

Homeostasis:

Maintenance of a constant condition in the internal environment Internal environment: extra cellular

fluid surrounding our cells

Homois = same, stasis= standingExamples: body temperature, water balance, ion balance, glucose levels, pH

Maintaining Homeostasis

Nervous System and the endocrine systemNegative Feedback Response – a stimulus is met by a response that reverses the trend of the stimulus

Receptors:

Detect stimuli, deviation from normal

Component of internal environment

Regulatory mechanisms

Negative Feedback Response

Anatomical Terms

Directional Terminology

Anatomical Position

Face ForwardArms at sidePalms forwardFeet forward

1. Prone and Supine

Supine: lying face up Referring to hand – palms forward

Prone: lying face down Referring to hand – palms are back

2. Anterior (ventral) vs. Posterior (dorsal)

Anterior - Referring to front of bodyPosterior – back side of body

Superior vs. inferior

Superior – refers to structures above anotherInferior – refers to a structure below another

Medial vs. Lateral

Medial – located closer to midlineLateral – located away from midline

Proximal vs. distal

Proximal – located closer to the point of originDistal – located away or “distant” from the point of origin.

Body Planes:

Sagittal: Vertically through

the body Divides body into

left and right portions

Frontal or Coronal Plane

Extends verticallyPerpendicular to sagittal planeDivides body into anterior and posterior halves

Transverse Plane or Horizontal plane

Divides the body into superior and inferior portions

Body Cavities

Dorsal body cavity Cranial cavity –

superior, hollow portion of skull, brain located

Spinal cavity – contains the spinal cord, vertebrae make up cavity

Ventral Body CavityVentral body cavity Thoracic cavity

Superior to diaphragm

Contents: Plural cavity (lungs)

Mediastinum – chest cavity space

Contents: pericardial cavity (heart), upper respiratory tract, esophagus, major blood vessels, thymus gland

Ventral Body Cavity

Abdominopelvic cavity

Inferior to diaphragm Abdominal cavity:

stomach, liver, gallbladder, spleen. Pancreas, small intestine, part of large intestine

Ventral Body Cavity

Abdominopelvic cavity Pelvic cavity: rest

of large intestine, bladder, rectum, reproductive organs