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The HUMAN BODYConcepts of

ANATOMY and PHYSIOLOGY

ANATOMY

• The scientific study of structures and the relationship of structures to each other.

• FORM

• Other terms include shape, structure, and appearance.

PHYSIOLOGY

• The scientific study of the functioning of specific body parts and systems.

• FUNCTION

Levels of Organization

• Chemical Level

• Cellular Level

• Tissue Level

• Organ Level

• System Level

• Organism Level

Levels of OrganizationChemical Level

•All chemical substances essential for maintaining life – atoms-compounds-molecules.

•Major Elements• C - carbon• H - hydrogen• O - oxygen• N - nitrogen

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Cellular Level

• The cell is the basic unit of structure and function.

• Each cell has a unique structure and function.• Muscle cells

• Nerve cells

• Blood cells

• Cartilage cells

Tissue Level

•Collection of similar cells grouped together to perform a specific function.

•Usually derived from a common embryonic origin.

•Four Major Tissue Types• Epithelial Tissue• Connective Tissue• Nervous Tissue• Muscular Tissue

Organ Level

• Structures composed of two or more different tissues.

• Have specific functions.

• Usually have recognizable shapes• Heart

• Brain

• Kidney

• Liver

System Level

• An association of organs that have a common function.• Digestive System

• Cardiovascular System

• Nervous System

• Lymphatic System

Organism Level

All body systems are functioning with one another as a living individual.

Metabolism

The sum total of all chemical processes that occur in the body.

Meta means"change"

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AnabolismUsing energy to synthesize or manufacture new tissue or

molecules.

Ana means “up” or “again”

Example: building muscle

CatabolismThe breakdown of tissues or chemical structures to produce or

generate energy.

Cata means “throwing down”Example: breaking down food molecules into glucose for energy

Anabolism vs. Catabolism

Body Positions and Descriptors

Anatomical Position

• In the anatomical position, the body is upright, directly facing the observer, feet flat and directed forward. The upper limbs are at the body’s sides with the palms facing forward.

Don’t worry . . .

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Position Descriptors• Anterior

• Front, or toward the front

• Posterior• Back, or toward the back

• Dorsal• Back, or toward the back (think of a whale’s dorsal fin)

• Ventral• Front, or toward the front (think of an air vent)

• Frontal• Front, or toward the front

• Lateral• On the side, or toward the side

• Medial/median• Middle, or toward the middle

Position Descriptors continued

• Proximal• Nearer to the point of attachment (such as the shoulder)

• Distal• Farther from the point of attachment

• Superior• Situated above, or higher than, another body part (cranial)

• Inferior• Situated below, or lower than, another body part (caudal)

• Peripheral• Away from the center

• Superficial• Close to the surface of the body

• Deep• Away from the surface of the body (think deep inside the body)

Position Descriptors Let’s Review

https://www.youtube.com/watch?v=kvHWnJwBkmo

Movement Descriptors

• flexion

• extension

• hyperextension

• abduction

• adduction

• circumduction

• plantar flexion

• dorsiflexion

• supination (LR)

• pronation (MR)

• inversion

• eversion

• elevation

• depression

• protraction

• retraction

Flexion, Extension, Hyperextension

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Abduction, Adduction, and Circumduction Dorsiflexion and Plantar flexion

Pronation and SupinationInversion and Eversion

Elevation and Depression Protraction and Retraction

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Movement Type Description Examples

Flexion Movement that decreases the joint angle, usually anteriorly in the sagittal plane Shoulder, knee, elbow, hip movement

Extension Movement the increases the joint angle, usually posteriorly in the sagittal plane. Shoulder, knee, elbow, hip movement

Abduction Movement away the midline of the body, usually in the frontal plane Shoulder, wrist, hip movement

Adduction Movement toward the midline of the body, usually in the frontal plane Shoulder, wrist, hip movement

Horizontal Abduction Movement away the midline of the body in the transverse plane Shoulder, wrist, hip movement

Horizontal Adduction Movement toward the midline of the body in the transverse plane Shoulder, wrist, hip movement

Internal (medial) Rotation Rotation toward away the midline of the body in the transverse plane Shoulder, hip movement

External (lateral) Adduction Rotation toward the midline of the body in the transverse plane Shoulder, hip movement

Lateral Flexion (right or left) Movement away the midline of the body in the frontal plane Neck, trunk movement

Rotation (right or left) Right or left rotation in the transverse plane Neck, trunk movement

Elevation Movement of the scapula (shoulder girdle) superiorly in the frontal plane Scapula movement

Depression Movement of the scapula (shoulder girdle) inferiorly in the frontal plane Scapula movement

Retraction Movement of the scapula (shoulder girdle) toward the spine in the transverse plane Scapula movement

Protraction Movement of the scapula (shoulder girdle) away from the spine in the transverse plane Scapula movement

Upward RotationSuperior and lateral movement of the inferior angle of the scapula (shoulder girdle)in the frontal plane

Scapula movement

Downward RotationInferior and medial movement of the inferior angle of the scapula (shoulder girdle)in the frontal plane

Scapula movement

Circumduction A compound circular movement involving flexion, extension, abduction, and adduction Shoulder, hip movement

Radial Deviation Abduction of the wrist in the frontal plane. (Same as abduction) Wrist movement

Ulnar Deviation Adduction of the wrist in the frontal plane. (Same as adduction) Wrist movement

OppositionDiagonal movement of the thumb across the palm of the hand to make contact with the5th digit

Thumb movement

Eversion Abduction of the ankle Ankle movement

Inversion Adduction of the ankle Ankle movement

Dorsiflexion Flexing the ankle so that the foot moves anteriorly in the sagittal plane Ankle movement

Plantarflexion Extending the ankle so that the foot moves posteriorly in the sagittal plane Ankle movement

Pronation (foot / ankle)Combined movements of abduction and eversion resulting in lowering of the medial(inner) margin of the foot.

Foot / ankle movement - Running on the inner edge of the foot.

Supination (foot / ankle)Combined movements of adduction and inversion resulting in raising of the medial(inner) margin of the foot.

Foot / ankle movement - Running on the outer edge of the foot.

Planes

Fixed lines of reference along which the body or organ is often divided to facilitate viewing.

Body Planes

Sagittal Plane

A vertical plane which divides the body or structure into right and left sections.

Sagittal Section of Thorax MRI of Brain

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Mid-Sagittal Plane

A vertical plane which divides a body or structure into equal right and left halves.

Frontal (Coronal) Plane

A vertical plane which divides a body or structure into anterior and posterior sections

X-Ray: Frontal View

Transverse (Horizontal) Plane

A horizontal plane which divides a body or structure into superior and inferior sections.

Transverse Plane(Cross Section)

Chest CT Scan

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Brain MRI Planes - Overview

BODY CAVITIES

Spaces within the body that contain the internal organs.

Body Cavities

Dorsal Body Cavity

• Cranial Cavity• Contains the brain

• Spinal (Vertebral) Cavity• Bony cavity formed by the vertebrae of the spine that contains and protects

the spinal cord.

Ventral Body Cavity

• Thoracic Cavity

• Pleural cavities (2)

• Space around each lung

• Mediastinum

• Divides the lungs into 2 cavities• Aorta and other great blood vessels (superior/inferior vena cava, etc)

• Esophagus

• Trachea

• Thymus

• Pericardial cavity

• Pericardial cavity• Heart

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Thoracic Cavity Ventral Body Cavity

• Abdominopelvic Cavity• Abdominal cavity

• Superior portion of the cavity that extends from the diaphragm to the superior margin of the pelvic girdle

• Pelvic cavity• Inferior portion of the cavity that is surrounded by the

pelvic bones

Abdominal Cavity Organs

•Viscera—collective term for the following:• Stomach• Liver

• Spleen• Gallbladder• Kidneys • Pancreas• Small intestines• Most of the large intestines

Pelvic Cavity Organs

• Urinary bladder

• Cecum

• Appendix

• Sigmoid colon

• Rectum

• Intestines

• Male or female reproductive organs

Abdominopelvic CavityBody Cavities

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Abdominopelvic Quadrants

• The abdominopelvic cavity can be functionally divided into quadrants.

• Used by clinical personnel to describe the location of abdominopelvic pain, tumors, and other abnormalities.

Abdominopelvic Quadrants

•Used mostly in the medical and clinical disciplines.

•Functionally divides the abdominopelvic cavity into four quadrants• RUQ - Right Upper Quadrant• LUQ - Left Upper Quadrant• RLQ - Right Lower Quadrant• LLQ - Left Lower Quadrant

Quadrants and Organs

• RUQ • liver, gallbladder, right kidney

• LUQ • stomach, spleen, pancreas, left kidney

• RLQ • appendix, right ovary

• LLQ • left ovary

Abdominopelvic Quadrants

Abdominopelvic RegionsHomeostasis

The ability of the body to maintain a constant internal environment within prescribed physiological limits.

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Parameters Maintained in Homeostasis

• gas concentrations

• temperature

• pressure

• pH (acidity)

• nutrients

• water

STRESS

•Any factor which disrupts homeostasis.

•Any stimulus which creates an imbalance in the body’s internal environment

•Anything that causes stress - Stressor• Physical• Emotional• Metabolic• Environmental

External Stressors

• Heat

• Cold

• Noise

• Light

• Exercise

Internal Stressors

• Pain

• Tumors

• High blood pressure

• Chemical imbalances

• Unpleasant thoughts

Feedback Mechanisms

Any circular situation in which information about something is monitored and sent to a control center

Components of a Feedback Mechanism

•Control Center• An area that receives information about a monitored

condition and determines an appropriate response.

•Receptor• An area or structure that monitors a controlled

condition.

•Effector• Structure that produces a response or changes a

controlled condition.

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Feedback Mechanisms Feedback Mechanisms

Types of Feedback Mechanisms

•Negative Feedback Mechanisms (Inhibitory)• The response counteracts the input.• The most common feedback mechanism.• Examples:

• blood pressure• blood sugar regulation• cardiac output• temperature regulation

•Positive Feedback Mechanisms (Stimulatory)• The response is intensified by the input.• Example: Breastfeeding by an infant, childbirth, and

blood clotting.

Negative Feedback System

Negative Feedback SystemPositive Feedback System

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Dorsal vs. Ventral (***Don’t worry, you won’t be tested on this picture)