Anatomy - the study of the structure of body parts & their relationship to one another
a. Gross (Macroscopic) Anatomy – the study of large (readily visible) body structures (heart, lungs, kidneys)
b. Microanatomy – the study of microscopic body structures; Cytology is the study of cells & Histology is the study of tissues
c. Regional Anatomy – the study of groups of structures in specific body regions
d. Systemic Anatomy – the gross anatomy of organ systems is studied
e. Surface Anatomy – the study of internal body structures as they relate to the body surface (skin)
Physiology - the study of the function of the bodyıs structural machinery
Negative Feedback: the product or response shuts off or reduces the level of the original stimulus; the variable then changes in a direction opposite the initial change
Examples of negative feedback mechanisms: regulation of body temperature, the withdrawal reflex, regulation of blood glucose levels by the hormones insulin & glucagon
Serous membranes: thin 2-layered membranes with fluid-filled space that covers the viscera within thoracic & abdominal cavities and lines walls of thorax & abdomen
- 2 layers:
o visceral layer: covers & adheres to organs within cavity
o parietal layer: lines walls of cavity
- Pleura: covers lungs within pleural cavities
- Pericardium: covers heart within pericardial cavity
- Peritoneum: covers abdominal viscera within abdominal cavity
Know the location of each of the following. Also know the subdivisions where appropriate (for example: the pleural cavity is within the thoracic cavity, which in turn is within the ventral body cavity).
Dorsal Body Cavity
- Cranial cavity
- Vertebral or Spinal cavity
Ventral Body Cavity
- Thoracic cavity
o Pleural cavity
o Mediastinum
o Pericardial cavity
- Abdominopelvic cavity
o Abdominal cavity
o Pelvic cavity
Abdominopelvic Quadrants
Energy – the capacity to do work
- Potential energy: stored energy that is available to do work
- Kinetic energy: energy of motion
Forms of energy:
Chemical energy – energy in the bonds of chemicals
Electrical energy – energy in the movement of charged particles
Mechanical energy – energy used directly to move matter (used by muscle cells)
Radiant energy – energy that travels in waves (includes solar energy, light energy)
Chemical Reactions:
Oxidation: loss of electrons or H atoms
Reduction: gain of electrons or H atoms
Exergonic reactions: release energy
Endergonic reactions: require (absorb) energy
The rate of a chemical reaction is influenced by:
1. temperature: molecules move faster as the temperature is increased (increases collisions) moderate temperature is best; high temperatures often denature (inactivate) enzymes
2. particle size: small molecules move faster (more (forceful) collisions)
3. concentration: usually increased reactant concentrations increases rate (more collisions)
4. catalysts: increase rate of chemical reactions without themselves being changed in the reaction enzymes are biological catalysts
Biochemistry:
Organic Molecules: Carbon-based molecules
Inorganic Molecules: Molecules that do not contain carbon and hydrogen (e.g.: salts, strong acids and bases, metal compounds)
Carbohydrates: (contain carbon, hydrogen, and oxygen atoms)
Monosaccharides: simple sugars with a backbone of 3 to 7 carbon atoms
Disaccharides: 2 monosaccharides joined by condensation
Polysaccharides include:
- Starch is a more moderately branched polymer of glucose, and is the storage form of carbohydrates in plant cells
- Cellulose is an unbranched polymer of glucose, with adjacent chains held together by hydrogen bonds, giving it a very rigid structure. It is the major structural component of plant cell walls
Lipids:
In the form of neutral fats (fats or oils)
One triglyceride = Glycerol + 3 fatty acids
Proteins:
Proteins are composed of chains of amino acid monomers
- Each amino acid has a central carbon bonded to an amino group, a carboxylic acid group, a hydrogen atom, and the remaining side chain (R group); it is the R group that differs in different amino acids
- the R groups do not normally bond between amino acids (the exception is cysteine, which forms disulfide (S-S) bonds within and between polypeptide chains for added strength
Denaturation: disruption of specific 3D structure of a protein by increasing temperature (boiling) or changing pH
Nucleic Acids:
Nucleic Acids are polymers of nucleotide monomers
- a nucleotide = a pentose sugar + a phosphate + a nitrogenous (nitrogen-containing) base
DNA:
DNA is the genetic material of the cell (inherited from parents)
- Composed of a sequence of four different nucleotides
- The 4 nucleotide subunits of DNA are named after the nitrogenous base each
contains; the 4 bases are : adenine (A), cytosine (C), guanine (G), & thymine (T)
- Adenine and Guanine are purine bases, and have very similar structures
- Cytosine and Thymine are pyrimidine bases, and have very similar structures
- DNA forms a double-helical structure (DNA is double-stranded)
- The 2 strands (nucleotide chains) of the double helix are complementary:
each base always pairs with its complement, so that the second strand of the double helix can be deduced, and synthesized in the cell, by simply pairing complementary bases
RNA:
- RNA is synthesized from 1 strand of DNA
- RNA does not form a double helix (no pairing of complementary bases between 2 strands); RNA is single-stranded
- RNA also uses 4 nucleotide subunits; however, uracil (U) replaces thymine in RNA
Chapter 3: Cells: The Living Units
Outer boundary of cells:
Plasma membrane: outer boundary of cells (except plant cells – also cell wall)
- phospholipid bilayer: semipermeable and selectively permeable
- functions in regulation of passage of molecules into and out of the cell
Facilitated Diffusion: passage of small molecules (glucose, amino acids) across the plasma membrane even though they may not be lipid-soluble
- a carrier protein assists movement of molecules down concentration gradient
- no energy is required
Filtration: a pressure gradient pushes solute-containing fluid (filtrate) from area of high pressure to area of low pressure
Cell adhesion molecules (CAMs): anchor cells to extracellular space & each other
- used by cells to assist in migration & recruit immune cells to sites of infection/injury
Cytosol:
Cytoskeleton: composed of microtubules, intermediate filaments, and actin filaments
- Functions in maintaining shape of cell and movement of subcellular structures
- Microtubules: composed of tubulin dimers coiled into tubelike structures
- Intermediate Filaments and actin filaments have structural roles throughout the cell
- Actin filaments combine with myosin in muscle cells to enable muscle movement
Endoplasmic Reticulum: (ER)
- Rough ER: associated with ribosomes; proteins translated on ribosomes associated with the rough ER will be transported and/or secreted outside cell
- Smooth ER: synthesizes phospholipids in all cells; various other cell type-specific functions
Microbodies: smaller version of lysosomes with specific enzyme activities
- Peroxisomes are microbodies that contain enzymes for oxidizing certain organic molecules with the release of hydrogen peroxide (toxic, but breaks down into water & oxygen)
Nucleus: stores genetic information in all eukaryotic cells
- DNA is organized into distinct chromosomes
- Within each nucleolus, ribosomal RNA is produced and joins with ribosomal proteins to form ribosomes
- The nucleus is bounded by a porous membrane, the nuclear envelope, which regulates passage of molecules into & out of the nucleus
Cell Division:
Cell Cycle: Consists of Interphase and Mitosis
Interphase: consists of G1, S, and G2 stages.
- S phase is the synthesis stage of the cell cycle, when the DNA is replicated.
- G1 stage is a growth (formerly gap) stage during which the organelles increase in number to produce enough for two new cells
- G2 stage is also a growth stage in which metabolism provides new metabolites and energy for the mitotic division
DNA Synthesis
DNA replication is carried out by the enzyme DNA Polymerase, as well as some additional protein factors
Mitosis: M stage
Prophase: chromatin condenses and the nuclear membrane begins disintegration. Mitotic spindle begins to assemble from microtubules in centrosomes, where centrioles form short asters prior to formation of spindle fibers.
Late Prophase: chromosomes attach to the spindle fibers, and are moved toward the center of the cell (metaphase plate). Spindle fibers attach to the kinetochores (attachment point of centromeres) of duplicated chromosomes. Nuclear membrane completes disintegration.
Metaphase: Chromosomes align at metaphase plate attached to kinetochore spindle fibers
Anaphase: Chromosomes move toward opposite poles of the cell due to disassembly of spindle fibers
Telophase: Chromosomes are at opposite poles of the cell; nuclear envelope reforms around each set of chromosomes, and spindle disappears. Cytokinesis begins
Cytokinesis:
- Animal cells divide by means of a cleavage furrow
- Plant cells divide using a cell plate to allow formation of a new plasma membrane and cell wall between the two new cells. Cell wall is too rigid for cleavage furrow
Gene Expression:
- DNA is transcribed to RNA in the nucleus
- transcription is carried out by a 5ı to 3ı RNA Polymerase, as well as additional protein factors
- the result of these modifications is mature mRNA
- Mature mRNA is translated to protein in the cytoplasm (at the ribosomes)
- tRNA molecules carry amino acids to the ribosome during translation (a tRNA for each amino acid)
- rRNA along with proteins comprise the structure of the 2 subunits of the ribosome
Chapter 4: Tissue: The Living Fabric
Epithelial Tissue (epithelium): a sheet of cells that lines a body cavity or covers a body surface
Simple Squamous Epithelial Tissue: single layer of flattened cells with disc-shaped nuclei & little cytoplasm
- locations: in kidney glomeruli, air sacs of lungs, heart lining, blood vessels & lymphatic vessels, lining of ventral body cavity
- functions: diffusion & filtration; secretes lubricating substances in serosae
Simple Cuboidal Epithelial Tissue: single layer of cube-shaped cells with large spherical nuclei
- locations: in kidney tubules, ducts of small glands, ovary surface
- functions: secretion & absorption
Simple Columnar Epithelial Tissue: single layer of column-shaped cells with oval nuclei; some have cilia or microvilli; may include goblet cells
- locations: nonciliated in most of digestive tract, gallbladder & excretory ducts of some glands; ciliated in small bronchi, some regions of uterus
- functions: absorption, secretion of mucus, enzymes; ciliated propels mucus, reproductive cells
Pseudostratified Columnar Epithelial Tissue: single layer of mostly column-shaped cells with different heights (some donıt reach apical surface) & nuclei at different levels; some have cilia; may include goblet cells
- locations: nonciliated in male sperm-carrying ducts & ducts of large glands; ciliated type lines trachea & most of upper respiratory tract
- functions: secretion & propulsion of mucus
Stratified Squamous Epithelial Tissue: multiple layers; basal layer cuboidal or columnar – carry out metabolism & mitosis; outer layers are keratinized
- locations: nonkeratinized type forms linings of esophagus, mouth & vagina; keratinized type forms epidermis of skin
- functions: protects underlying tissues
Stratified Columnar Epithelial Tissue: several layers – basal layer usually cuboidal
- locations: male urethra & some large ducts of glands
- functions: protection, secretion
Transitional Epithelial Tissue: several layers – basal layer cuboidal or columnar; surface cells dome-shaped or squamous-like (depending on stretch)
- locations: ureters, bladder & part of urethra
- functions: stretches & distends urinary organ
Connective Tissue: most abundant primary tissue
- extracellular matrix (collagen or elastin fibers; calcium phosphate (bone)
Ground Substance: fills space between cells & contains fibers
- composed of interstitial fluid, cell adhesion proteins & proteoglycans
Connective Tissue Types:
Areolar Connective Tissue: gel-like matrix with all 3 fiber types; fibroblasts, mast cells, macrophages & some white blood cells
- location: under many epithelia (forms lamina propria); around organs & capillaries
- functions: cushions organs; many immune cells regulate immunity
Adipose Connective Tissue: closely packed adipocytes (fat cells with large fat droplet)
- location: under skin, around kidneys & eyeballs, within abdomen, breasts
- functions: cushions organs; reserve food fuel, insulation
Reticular Connective Tissue: reticular fiber network in loose ground substance; reticular cells
- location: lymphoid organs
- functions: internal skeleton for support of other cell types
Dense Regular Connective Tissue: dense (primarily) parallel collagen fibers, few elastin fibers; fibroblasts
- location: tendons, ligaments, aponeuroses
- functions: attaches muscles to bone & other muscles, attaches bones to bones; withstands high stress
Dense Irregular Connective Tissue: irregular shaped collagen fibers, few elastin fibers; fibroblasts
- location: dermis of skin, digestive submucosa, fibrous capsules of organs & joints
- functions: withstands tension, adds structural strength
Hyaline Cartilage: amorphous firm matrix; collagen fibers form glassy (invisible) network; chondrocytes in lacunae
- location: embryonic skeleton, covers long bones in joints, costal cartilage of ribs, cartilage of nose, trachea & larynx
- functions: support, cushioning, resists stress
Elastic Cartilage: similar to hyaline cartilage, with elastin fibers in matrix
- location: external ear (pinna), epiglottis
- functions: maintains shape while adding flexibility
Fibrocartilage: similar to hyaline cartilage, less firm with thick collagen fibers in matrix
- location: intervertebral discs, pubic symphysis, knee joint discs
- functions: tensile strength, absorbs shock
Bone: hard calcified matrix, many collagen fibers, well vascularized, osteocytes in lacunae
- location: bones
- functions: support, levers for muscles, calcium storage, blood cell formation (hematopoiesis) in marrow
Blood: red blood cells (erythrocytes) & white blood cells (leukocytes) in fluid matrix (plasma)
- location: in blood vessels
- functions: transports oxygen & carbon dioxide, nutrients, wastes & other substances
Nervous Tissue: neurons & supporting cells
- location: brain, spinal cord & nerves
- functions: transmit electrical signals from sensory receptors to effectors
The Skin (Integument): composed of 2 regions:
- Epidermis: outermost layer composed of epithelial cells
- Dermis: underlying layer composed of fibrous connective tissue; vascularized
Hypodermis: subcutaneous layer just deep to the dermis
- mostly adipose with some areolar connective tissue
- insulates, absorbs shocks, & anchors skin loosely to muscles
Epidermis: keratinized stratified squamous epithelium
- 4 distinct cell types:
o keratinocytes: produce the fibrous protein keratin
§ tightly connected by desmosomes
§ outermost cells dead & keratinized; lifespan of 25-45 days
§ thick skin has accelerated cell division & keratinization
o melanocytes: spider-shaped cells that produce the pigment melanin
§ located in deepest layer of epidermis; melanosomes in melanocyte processes transfer melanin to keratinocytes
§ melanin granules protect the cell nucleus from UV radiation
o Langerhansı cells (epidermal dendritic cells): macrophages; part of immune system
§ produced in bone marrow; migrate to epidermis & form network around keratinocytes
o Merkel cells: associate with disclike sensory nerve endings to form Merkel disc – a sensory receptor for touch
Layers of Epidermis:
- Thick skin has 5 layers (strata)
o Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum & stratum corneum
- Thin skin has only 4 layers missing stratum lucidum; stratum corneum thinner
Stratum Basale (Stratum Germinativum): basal layer; deepest epidermal layer firmly attached to dermis
- single layer of cells; cell division produces new keratinocytes for all layers
Stratum Spinosum: several layers thick; interrupted by dermal papillae
- keratinocytes are flat & spiny (prickle cells)
- some melanin granules; Langerhansı cells
Stratum Granulosum: 3-5 cell layers thick; cells contain granules
- keratohyaline granules: help in keratin formation
- lamellated granules: contain waterproofing glycolipid – released into extracellular space to prevent water loss
Stratum Lucidum: a few rows of clear, flat dead keratinocytes
- only in thick skin
Stratum Corneum: outermost layer; 20-30 cell layers thick
- protects skin with keratin & thick plasma membranes; glycolipids prevent water loss
Dermis: strong, flexible connective tissue
- fibroblasts, macrophages, mast cells & white blood cells with collagen, elastin & reticular fibers
- rich supply of nerve fibers, blood vessels & lymphatic vessels
- houses hair follicles, oil & sweat (sudoriferous) glands
- papillary layer: upper layer composed of areolar connective tissue
o dermal papillae: projections that indent the epidermis; contain capillary loops & touch receptors (Meissnerıs corpuscles)
o dermal ridges on palms of hand & soles of feet form epidermal ridges – genetically determined pattern of ridges; leaves fingerprint
- reticular layer: lower layer (most of thickness of dermis); composed of dense irregular connective tissue
o thick collagen fiber bundles form lines of cleavage (tension lines) in skin; used in surgery (incisions made parallel to lines to speed healing)
o flexure lines: dermal folds near joints
Skin Color: dictated by 3 pigments: melanin, carotene, & hemoglobin
- melanin: tyrosine polymer; relies on enzyme tyrosinase in melanocytes
o protects cell nucleus from UV light-induced mutations; UV repair mechanisms may stimulate synthesis
- carotene: yellow-orange pigment found in plants (carrots)
o accumulates in stratum corneum & hypodermis; most evident in thick skin
- hemoglobin: oxygenated hemoglobin in dermal capillaries gives fair skin a pinkish color
Skin Appendages:
Sweat (sudoriferous) glands: eccrine & apocrine
- eccrine sweat glands (merocrine sweat glands): far more numerous – most abundant on palms of hands, soles of feet & forehead
o secrete sweat: hypotonic blood filtrate 99% water with salts, vitamin C, antibodies, metabolic wastes & lactic acid
o sweat prevents overheating; regulated by sympathetic division of autonomic nervous system
- apocrine sweat glands: mostly confined to axillary & anogenital regions
o ducts empty into hair follicles
o in addition to components of sweat, secretion contains lipid & proteins
- ceruminous glands: modified apocrine glands in the external ear canal
o secrete cerumen (earwax); deters insects & blocks foreign material
Sebaceous (oil) glands: simple alveolar glands (holocrine glands); located all over body except palms of hand & soles of feet
- secrete sebum (rich in oils) into hair follicle (or pore) bacteriocidal; lubricates hair & skin
- inflammation/infection can lead to acne; overactivity leads to seborrhea
Hair & hair follicles:
- hair (pili) are flexible strands of mostly dead, keratinized cells
- melanin from melanocytes at base of follicle produces color
- hair follicle: extends from epidermal surface to dermis or hypodermis
o arrector pili muscle: smooth muscle bundle that contracts to raise hair
- types of hairs: short, fine vellus hairs; longer, coarser terminal hair
- alopecia: hair loss brought on by aging & hormones
Nails: scalelike epidermal modifications at dorsal surface of distal region of fingers & toes
- nail matrix cells produce new growth
- meet skin at folds of skin called nail folds & cuticle
Bone structure:
Gross anatomy of long bones:
- Compact bone: dense outer layer of bone
- Spongy bone (cancellous bone): trabeculae – needle-like or flat pieces internal to compact bone; spaces between trabeculae filled with red or yellow bone marrow
- Diaphysis (shaft): forms long axis of bone; thick collar of compact bone surrounding medullary (marrow) cavity
o In adults, marrow cavity contains fat – yellow bone marrow cavity
- Epiphyses: ends of bone; often more expanded than diaphysis; outer compact & internal spongy bone
- Membranes: periosteum covers entire surface of bone except joint surfaces;
o endosteum: covers trabeculae of spongy bone & canals of compact bone
Hematopoietic tissue in bones:
- Hematopoiesis occurs in red marrow (in cavities of spongy bone of long bones & diploe of flat bones)
- In infants, medullary cavity & all spongy bone have red bone marrow
- In adults, red bone marrow in the head of the femur & humerus, & diploe of flat bones & some irregular bones (hip bone)
- During anemia (blood cell deficiency), yellow marrow can revert to red marrow
Microscopic structure of bone:
Compact bone (lamellar bone): units called osteons or Haversian systems
- osteons: cylinder oriented parallel to long axis of bone; within each cylinder is tubes (concentric circles) of bone matrix (lamellae)
- central (Haversian) canal: runs through center of osteon; carries blood vessels & nerve fibers
- perforating (Volkmannıs) canal: at right angles to long axis; connect blood vessels & nerves of periosteum to those of central canals & medullary cavity
- osteocytes: bone cells in small cavities called lacunae
- canaliculi: connect lacunae to each other & central canal
- interstitial lamellae: partially formed fill gaps or have been replaced
- circumferential lamellae: extend around all osteons within shaft (just deep to periosteum)
Spongy bone: trabeculae a few cell layers of irregularly arranged lamellae & osteocytes connected by canaliculi
- no osteons; nutrients delivered by capillaries in endosteum
Chemical composition of bone:
- organic component: cells (osteocytes, osteoblasts & osteoclasts) & osteoid (organic matrix ground substance & collagen fibers)
- inorganic component: hydroxyapatites (mineral salts); mostly calcium phosphates
- calcium salt crystals pack around collagen fibers in matrix
Control of Remodeling:
Hormonal control:
- parathyroid hormone (PTH, from parathyroid gland): stimulates osteoclasts to resorb bone to raise blood calcium levels
- calcitonin (from parafollicular (C) cells of thyroid): inhibits osteoclasts & stimulates calcification of bone matrix to lower blood calcium levels
Osteomalacia: bones are inadequately mineralized (osteoid not calcified)
- symptoms: pain when weight placed on bones
- cause: insufficient dietary calcium or vitamin D (helps to absorb dietary calcium from intestine)
- treatment: calcium & vitamin D supplements & sunlight
Osteoporosis: bone resorption outpaces bone deposit
- normal bone matrix composition, but bone mass is reduced & bones are porous
- causes: many, including hormonal deficiencies (especially steroid hormone deficiency due to decline in old age), insufficient exercise, poor diet,
- treatment: calcium & vitamin D supplement, & hormone replacement therapy (HRT)
Pagetıs disease: excessive bone formation & breakdown
- Pagetic bone : abnormally high ratio of spongy bone to compact bone
- symptoms: progressive weakening & deformity of bones (esp. spine, pelvis, femur & skull)
- cause: unknown, may be viral
- treatment: calcitonin & drug therapy to prevent bone breakdown
Chapter 7: The Skeletal System
- consists of bones arranged along (longitudinal) axis of body
- includes: skull bones, auditory ossicles (ear bones), hyoid bone, ribs, sternum (breastbone) & vertebral column (backbone)
- consists of the bones of the upper & lower limbs (extremities), & the bones forming the pectoral & pelvic girdles (shoulder & hip bones) that connect the limbs to the axial skeleton
Bone Types:
- long bones: have greater length than width; consist of diaphysis (shaft) & epiphyses; slightly curved to absorb stress
o includes: femur, tibia & fibula, humerus, radius & ulna & phalanges of fingers & toes
- short bones: cube-shaped; spongy bone with thin outer layer of compact bone
o includes: carpal (wrist) bones (except pisiform, which is a sesamoid bone) & tarsal (ankle) bones (except calcaneus, which is an irregular bone)
- flat bones: thin; composed of 2 parallel plates of compact bone enclosing a layer of spongy bone
o offer protection & broad surface for muscle attachment (tendons)
o includes: cranial bones, sternum & ribs, & scapulae (shoulder blades)
- irregular bones: complex shapes; donıt fit into other categories
o includes: vertebrae, coxal (hip) bone, calcaneus (heel bone), & some facial bones
- sesamoid bones: sesame shaped bones that develop in tendons to protect against friction & stress
o includes patellae (kneecaps) & pisiform (smallest wrist bone)
- sutural bones: small bones located within immoveable joints (sutures)
o vary in number among individuals & not included in named bones
- Know the bones & features including basic locations for each & placing features with correct bones
Classification of Joints:
- Functional Classification:
o Synarthroses: immovable joints (sutures)
o Amphiarthroses: slightly movable joints (symphyses)
o Diarthroses: freely movable joints (most joints)
Fibrous Joints: bones joined by fibrous tissue; no joint cavity
- most are immovable or slightly movable
- sutures: between bones of the skull
o joined with short connective tissue fibers in middle age, connective tissue ossifies forming synostoses
- syndesmoses: bones connected by ligament; immovable or slightly movable
o examples include connections between bones of lower arm (radius & ulna) & lower leg (tibia & fibula)
- gomphoses: peg in socket joint; only example is tooth in bony alveolar socket
o connected by short periodontal ligament
Cartilagenous Joints: bones joined by cartilage; no joint cavity
- synchondroses: bones joined by hyaline cartilage; almost always synarthrotic
o examples are epiphyseal plates in long bones of children, joint between costal cartilage of first rib & manubrium of sternum
- symphyses: articular surfaces of bone covered with hyaline cartilage fused to plate of fibrocartilage
o fibrocartilage compressible – shock absorber, but limited movement; joints are amphiarthrotic
o examples are intervertebral joints (discs) & pubic symphysis
Synovial Joints: bones separated by fluid-containing joint cavity
- all are freely movable
- rich supply of blood vessels & nerve endings (sense stretch)
- articular cartilage: hyaline cartilage protects bone ends
- joint (synovial) cavity: potential space with synovial fluid
- articular capsule: external fibrous capsule (dense irregular CT) & internal synovial membrane (loose CT)
- synovial fluid: occupies free spaces in joint cavity; reduces friction
o mostly blood filtrate; viscous fluid containing hyaluronic acid
o weeping lubrication: fluid forced from cartilage during compression & soaked back up when pressure is relieved
Angular movements: increase or decrease angle between 2 bones
- Flexion: decreases angle of joint & brings bones closer together
- Extension: increases angle of joint & moves bones away from each other
o Hyperextension: moving head backwards beyond straight
- Dorsiflexion: lifting foot
-