Introduction to the Human Body Anatomy tome means

Introduction to the Human Body

Anatomy • “tome” means to cut in Greek • Describes the structures of the body: – what they are made of – where they are located – associated structures

• All physiological functions are performed by specific anatomical structures • Principle of complementarity says that structure and function are complementary – Function always reflects structure – What a structure can do depends on its specific form

• Key to anatomy is understanding function – For example: Left side of heart is larger than right. – Why is that? Structure (anatomy) and function (physiology) are intimately related

Gross Anatomy • Structures large enough that one can see with the unaided eye – Surface Anatomy - study of superficial markings – Regional Anatomy - The study of specific areas of the body (e. g. head, trunk) – Systemic Anatomy - Study of the 11 specific organ systems

Microscopic Anatomy • Involves studying anatomical structures that cannot be seen with the unaided eye 1. Cytology - cells 2. Histology - tissue

Levels of Organization • Chemical Level: - atoms (e. g. carbon) combine to form molecules (e. g. glucose) • Cellular level: – Smallest living units in organisms – Cells contain organelles, each with a function • Tissue level - different groups of cells that perform a function • Organ Level - Different types of tissues that perform a common function • Organ system – consists of different organs that work closely together

Levels of Structural Organization Smooth muscle cell Molecules 2 Cellular level Cells are made up of molecules. Atoms 1 Chemical level Atoms combine to form molecules. 3 Tissue level Tissues consist of similar types of cells. Smooth muscle tissue Heart Cardiovascular system Epithelial tissue Smooth muscle tissue Connective tissue 4 Organ level Organs are made up of different types of tissues. Blood vessels Blood vessel (organ) 6 Organismal level The human organism is made up of many organ systems. 5 Organ system level Organ systems consist of different organs that work together closely.

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

Body systems: 1 -INTEGUMENTARY ORGANS • Skin FUNCTIONS • Waterproofs, cushions, protects deeper tissue • Excretes salts, pain, pressure • Regulates body temp, synthesize vitamin D

2 -SKELETAL ORGANS • Bones, cartilages, ligaments, joints FUNCTIONS • Protects & supports body organs • Framework for muscles & movement • Store minerals

3 - MUSCULAR ORGANS • Skeletal muscle (attached to bone) FUNCTIONS • Contraction & mobility (locomotion) • Facial expression, posture • Produce body heat

4 - NERVOUS ORGANS • Brain, spinal cord, nerves, & sensory receptors FUNCTIONS • Fast-acting central control system • Responds to external/internal stimuli via nerve impulses (electrical messages)

5 - ENDOCRINE ORGANS • Pituitary, thyroid, parathyroids, adrenals, thymus, pancreas, pineal, ovaries, testes…. . . FUNCTIONS • Slow-acting control system • Glands produce hormones that regulate growth, reproduction, metabolism…. .

6 - Circulatory ORGANS • Heart, blood vessels, capillaries &blood FUNCTIONS • Carries O 2 nutrients, hormones, & other substances to and from tissue cells • White blood cells protect against bacteria, toxins, tumors

7 - LYMPHATIC ORGANS • Lymphatic vessels, lymph nodes, spleen, tonsils FUNCTIONS • Complements circulatory system by returning leaked fluid back to blood vessels • Cleanses the blood; involved in immunity

8 - RESPIRATORY ORGANS • Nasal cavity, pharynx, larynx, trachea, bronchi & lungs FUNCTIONS • Keeps blood supplied with O 2 & removes CO 2 • Carries out gas exchanges through air sacs in lungs

9 - DIGESTIVE ORGANS • Oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus (liver & pancreas) FUNCTIONS • Breaks food down into absorbable units that enter the blood; indigestible food eliminated as feces

10 - URINARY (EXCRETORY) ORGANS • Kidney, ureter, urinary bladder, urethra FUNCTIONS • Eliminates nitrogenous waste from the body (urea & uric acid) • Regulates water, electrolytes, & acid-base balance of the blood

11 - REPRODUCTIVE ORGANS • Male – Seminal vesicles, prostate, penis, vas deferens, testis, scrotum • Female – Ovaries, mammary glands, uterus, vagina, uterine tube FUNCTIONS • Primary function for both sexes is to produce offspring • Male – testes produce sperm & male sex hormones • Female – ovaries produce eggs & female sex hormones; mammary glands for nourishment

Anatomical terms

Anatomical Position – Standing erect – Feet parallel – Arms hanging at the sides – Palms facing forward

Anatomical Position • Hands at sides, palms forward

Orientation of terms • Note that Left/Right are reversed in anatomical figures • WHY?

Directional terms • Superior (cranial) – toward the head end or upper part of a structure or body; above • Inferior – away from the head end or toward the lower part of a structure or body; below • Anterior (ventral) – toward or at the front of the body; in front of • Posterior (dorsal) – toward or at the backside of the body; behind • Medial – toward or at the midline of the body; on the inner side of • Lateral – away from the midline of the body; on the outer side of

• Proximal – close to the origin of the body part or the point of attachment of a limb to the body trunk. • Distal – farther from the origin of a body or the point of attachment of a limb to the body trunk. • Superficial (external) – toward or at the body surface. • Deep (internal) – away from the body surface; more internal.

1. 2. 3. 4. 5. 6. 7. 8. 9. The navel is -------to the breastbone The heart is ------- to the breastbone The arms are ------ to the chest The elbow is ------ to the wrist The skin is ------- to the skeleton The forehead is --------- to the nose The breastbone is------ to the spine The heart is ------to the arm The armpit is -----between the breastbone and the shoulder 10. The knee is -----to the thigh 11. The lungs are -----to the rib cage

Examples: • The navel is inferior to the breastbone • The heart is posterior to the breastbone • The arms are lateral to the chest • The elbow is proximal to the wrist • The skin is superficial to the skeleton • The forehead is superior to the nose • The breastbone is anterior to the spine • The heart is medial to the arm • The knee is distal to the thigh • The lungs are deep to the rib cage

Body planes and sections A section is a cut made along a plane • Sagittal – cut made along the lengthwise or longitudinal plane of the body dividing it into left and right parts • Midsagittal (median) plane – right and left parts are of equal size • Frontal (coronal) plane – cut made along a lengthwise plane that divides the body into anterior and posterior parts • Transverse plane (cross section) – cut made along a horizontal plane dividing the body or organ into superior and inferior parts

Planes • Sagittal Plane – divides body into right and left parts. • Midsagittal =median plane –divides body into two equal halves.

Planes • Frontal = coronal plane – divides body into anterior and posterior parts

Planes • Transverse plane = cross Section= horizontal section divides into upper and lower parts

Body planes and sections - cut into sections along a flat surface called a plane (also called coronal) (also called XS – cross section)

Anatomical Movements

• Supine – Lying on your back • Prone – Lying face down 35

Movements: • Flexion – decreasing the angle between two joints • Extension – increasing the angle between two joints • Hyperextension – occurs beyond extended position 36

• Abduction – moving away from the midline of the body or body part • Adduction – moving toward midline of body or body part 37

• Elevation – moving to superior position • Depression – moving to inferior position 38

• Supination – rotating forearm laterally • Pronation – rotating forearm medially 39

• Inversion – lifting the medial border of the foot • Eversion – lifting the lateral border of the foot 40

• Dorsiflexion – moving the top of the foot toward the shin • Plantar flexion – moving the sole of the foot downward (pointing toes) 41

• Circumduction – flexion, abduction, extension & adduction in a sequence 42

• Rotation – Turning about the vertical axis of the bone 43