Term
4 Types of Primary Tissues in the body |
|
Definition
Epithelial tissue: Covering Connective Tissue: Support Muscle Tissue:Movement Nervous Tissue:Control, they are innervated |
|
|
Term
Characteristics of Epithelial Tissue |
|
Definition
they exhibit polarity, lower atached basal surface,upper free apical surface, They are avascular- lack blood vessels,supported by basement membrane,connective tissue supports all epithelial tissues,they have a high regenerative capacity |
|
|
Term
2 main classes of epithelial tissue |
|
Definition
Membranous epithelia and Glandular epithelia |
|
|
Term
|
Definition
covering and lining epithelia 2 Types: Simple epithelia and Stratified Epithelia |
|
|
Term
|
Definition
form the glands that secrete products in the body |
|
|
Term
|
Definition
composed of a single layer of epithelial cells simple squamous, simple cuboidal,simple columnar,Pseudostratified columnar |
|
|
Term
|
Definition
composed of at least 2 layers of epithelial cells: named for the epithelial cell type on the apical surface of the epithelia stratified squamous, stratified cuboidal, stratified columnar, Transitional epithelium |
|
|
Term
3 Major Types of Epithelial Cells based on shape |
|
Definition
Squamous cells : flattened, scale-like cells with flattened disc-shaped ( spindle-shaped) nuclei.
Cuboidal cells: Cube-like or box-like cells with centrally-placed spherical nuclei.
Columnar cells: Tall, column-shaped cells with elongated nuclei placed closer to the base of the cells. |
|
|
Term
|
Definition
2 classes of glands
Endocrine glands = secrete their products ( hormones) directly into extracellular fluid
Exocrine glands = secrete their product onto body’s surfaces
2 types of Exocrine glands: Unicellular Exocrine glands and Multicellular glands
Unicellular exocrine glands = the only unicellular exocrine glands are Goblet cells which are scattered within membranous epithelia.
Goblet cells secrete Mucin (Mucin + Water = Mucus) |
|
|
Term
Multicellular Exocrine Glands |
|
Definition
Functional Classification of Multicellular Exocrine glands = Mode of Secretion
Apocrine = apex of the secretory cell pinches off to release accumulated products.
Merocrine = the secretory cell undergoes exocytosis to release products.
Holocrine = the secretory cell ruptures to release its accumulated products. |
|
|
Term
Characteristics of Connective Tissues |
|
Definition
All connective tissues are derived from the embryonic tissue called MESENCHYME -They exhibit a degree of vascularity 3. Composed of 2 parts: Nonliving portion and the living portion
Nonliving portion = Extracellular matrix = Ground substance and the fibers Ground substance composed of interstitial fluid, cell adhesion molecules and proteoglycans Fibers – 3 types: Collagen fibers = “white” fibers Elastic fibers = “yellow” fibers
Reticular fibers Living portion = Cells that are derived from mesenchyme and they produce the connective tissue
Fibroblasts – produce connective tissue proper Chondroblasts = produce cartilage
Osteoblasts= produce bone tissue
hematopoietic stem cell = produce blood cells |
|
|
Term
Elastic Connective Tissue |
|
Definition
Description:Dense regular CT with high content of Elastic fibers.
Function: Exhibit the stretch-recoil properties
|
|
|
Term
|
Definition
Has a semi-solid ground substance
3 types of Cartilage:
1. Hyaline cartilage-embryonic cartilage epiphyseal plates articular cartilage costal cartilage
2. Elastic cartilage epiglottis pinna
3. Fibrocartilage intervertebral discs |
|
|
Term
|
Definition
Living portion = Osteoblasts - produce bone tissue Solid matrix Nonliving portion = Extracellular matrix Organic matrix = osteoid – ground substance + fibers Inorganic matrix = hydroxyapatites= calcium phosphate crystals |
|
|
Term
Membranes as simple Organs |
|
Definition
Cutaneous membrane = Keratinized stratified squamous epithelium/areolar and dense irregular connective tissue
Mucous membrane = Nonkeratinized stratified squamous epithelium /areolar CT or Simple columnar epithelium / areolar CT The areolar CT in mucous membrane is specifically referred to as LAMINA PROPRIA
Serous membrane = Simple squamous epithelium/areolar CT simple squamous epithelium in serous membrane is specifically referred to as the MESOTHELIUM
Synovial membrane = dense irregular CT/areolar CT |
|
|
Term
2 Divisions of the Integumentary system |
|
Definition
Skin = integument = Cutaneous membrane Skin is the largest organ of the body – surface area of 1.2 to 2.2 square meters; weighs 9 to 11 pounds (4-5kg) = 7% of the total body weight Composed of the superficial EPIDERMIS and the deeper
DERMIS 2. Accessory skin structures = skin appendages: i) Sweat (sudoriferous) glands ii) Sebaceous ( oil) glands iii) Hair/hair follicles iv) Nails |
|
|
Term
|
Definition
Stratum Basale – deepest stratum Stratum Spinosum – contains tonofilaments Stratum Granulosum – contains granules Stratum Lucidum – present only in thick skin Stratum Corneum - superficial stratum |
|
|
Term
|
Definition
The deepest stratum. A single layer of cells including Keratinocytes, Melanocytes, Merkel cells: Keratinocytes are mitotically active producing cells for the superficial layers hence, the stratum basale is also known as the stratum Germinativum Melanocvtes produce the pigment MELANIN contained in melanosomes – melanosomes accumulate on the superficial surface of the keratinocvtes in the stratum basale. Melanin acts as a chemical shield to protect the nuclei of the keratinocytes from the harmful effects of UV radiation in sunlight. Melanin gives skin its color. Albinism- genetic condition in which melanin is not synthesized When you go out into the sun, these cells make extra melanin to protect you from getting burned by the sun's ultraviolet, or UV, rays = tanning Merkel cells at the epidermal-dermal junction associate with free nerve endings to form Merkel Discs which act as Touch receptors |
|
|
Term
|
Definition
Several layers of cells Cells are connected by desmosomes – hold cells together which cause the cells to appear “spiny” during histological preparation Cells contain intermediate filaments called Tonofilaments Epidermal dendritic cells – Langerhans’ cells in the stratum spinosum act as macrophages to engulf and digest pathogens |
|
|
Term
|
Definition
Composed of 3-5 layers of cells Cells contain 2 types of granules: Lamellated granules – contain Glycolipids – the lipids make the epidermis water-proof. keratohyaline granules – contain the tough, insoluble protein, Keratin, which makes the epidermis tough and abrasive- resistant |
|
|
Term
|
Definition
Thin, translucent layer of dead cells Thickens the epidermis Present only in thick skin – palms, soles |
|
|
Term
|
Definition
Superficial layer of the epidermis Composed of 20-30 layers of dead, flat cells Dead cells are impregnated with glycolipids and keratin to provide a tough, durable, water-proof “coat”. Replaced every three to four weeks |
|
|
Term
|
Definition
Consists of the superficial PAPILLARY layer and the deep RETICULAR layer The papillary Layer Composed of areolar CT Surface has peg-like projections called DERMAL PAPILLAE – house blood capillaries and nerve endings and Meissner’s corpuscles which act as touch receptors In thick skin, the surface of the papillae are supported by mounds called Dermal Ridges which form impressions on the epidermal surface called the EPIDERMAL RIDGES (= friction ridges) – increase friction and enhance gripping Pattern of epidermal ridges is genetically determined and therefore unique to an individual – acts as the basis for finger-printing |
|
|
Term
Reticular Layer of the Dermis |
|
Definition
Deeper layer accounting for 80% of the dermis Composed of dense irregular CT Contains the touch receptors for deep pressure called Pacinian corpuscles Cleavage (tension) lines – areas of the reticular layer with less collagen bundles Incisions made parallel to the cleavage lines gape less and therefore heal faster. Striae ( stretch marks) – indicate dermal tearing replaced by slivery white scars |
|
|
Term
Location of the Nervous Structures in the Skin |
|
Definition
Merkel discs: epidermal-dermal junctions; act as light touch Meissner’s Corpuscles: Papillary layer of the dermis; act as touch receptors
Root hair plexus: wrapped around the base of a hair follicle called the hair bulb and it’s stimulated when the hairs bend; act as touch Pacinian Corpuscles: located in the reticular layer of the dermis and they respond to deep pressure placed on the skin |
|
|
Term
Accessory Structures of the Skin All derived from the epidermis but reside in the dermis: |
|
Definition
Sweat glands(sudoriferous),Sebaceous glands(oil glands),Hairs/hair follicles,Nails |
|
|
Term
|
Definition
Also known as sudoriferous glands Simple coiled tubular multicellular exocrine glands 2 types: Eccrine and Apocrine Eccrine Sweat Glands: 3 million per person Abundant in the palms, soles and forehead Secrete SWEAT Use the MEROCRINE mode of secretion Hence, the eccrine sweat glands are also known as merocrine sweat glands |
|
|
Term
|
Definition
Hypotonic filtrate of blood 99% water Antibodies Vitamin C Salts – NaCl Metabolic wastes Dermicidin – antimicrobial protein pH between 4-6 = Acidic ACIDIC MANTLE – acidic pH of sweat prevents microbial growth on the surface of the skin |
|
|
Term
|
Definition
Become active after puberty when they are stimulated by the sex steroid hormones Secrete a viscous, yellowish fluid onto hair follicles Secrete their product via MEROCRINE mode of secretion Secretion is associated with body odor hence, the apocrine sweat glands are also known as “ODORIFEROUS” glands |
|
|
Term
2 Specialized Sweat Glands |
|
Definition
Ceruminous glands: specialized sweat glands located in the lining of the external ear canal; they secrete a bitter substance called CERUMEN(earwax) which prevents entry of foreign objects such as, insects and water, into the ear
Mammary glands: specialized sweat glands located in breasts; secrete milk to feed the young |
|
|
Term
Sebaceous Glands(oil glands) |
|
Definition
Also known as Oil glands Simple alveolar glands Found all over the body except the palms/soles Secrete an oily substance called SEBUM into hair follicles and via pores to the surface of the skin Sebum softens and lubricates hair and skin Secrete via the HOLOCRINE mode of secretion Whiteheads: sebum accumulated in the ducts of the sebaceous glands Blackheads: popped whiteheads that result in oxidation and darkening Acne: inflammation of sebaceous glands caused by bacteria |
|
|
Term
|
Definition
Produced by cells in the MATRIX inside hair follicles Each hair has 2 regions – shaft and root SHAFT – region exposed above the skin ROOT – region below the skin enclosed by the hair follicle |
|
|
Term
3 Concentric Layers of hair |
|
Definition
Hair is composed of 3 concentric layers of keratinized cells: Inner medulla – the core Middle cortex – the largest layer Outer cuticle – a single layer of overlapping cells that protects the underlying layers and to prevent hair from matting Conditioners keep the cuticle smooth to prevent matting of the hair and split ends Alopecia – rate of hair loss outpaces rate of hair growth |
|
|
Term
|
Definition
For protection; hair on scalp, eyelashes To provide insulation: in cold weather, bands of smooth muscle attached to the hair follicles called the arrector pili muscles, contract pulling the hair follicles and hairs from an oblique position to an upright position resulting in dimpling of the skin referred to as “goose bumps”; in this position a layer of air can be trapped on the surface of skin to act as an insulator to prevent heat loss from the body |
|
|
Term
|
Definition
Basal Cell Carcinoma: involves the proliferation of stratum basal basale cells. The least malignant and most common type of skin cancer ( 80% ); grows slowly Squamous Cell Carcinoma: involves the cells in the stratum spinosum. Second most common type of skin cancer; grows rapidly Melanoma: proliferation of the melanocytes; most aggressive type of skin cancer, highly metastatic and resistant to chemotherapy; least common |
|
|
Term
|
Definition
Tissue damage by intense heat, radiation, electricity and chemicals such as acids Classified based on severity: First-degree burns – damage is confined to only the epidermis; associated with redness, swelling and pain; heal in 3day without medical intervention. Ex. Sunburn Second-degree burns – damage to the entire epidermis and the papillary layer of the dermis; associated with blisters ( fluid collection at the epidermal-dermal junction), swelling, redness and pain; heal in 3-4 weeks if infection is prevented Third-degree burns – damage to the entire skin= damage to the entire epidermis and dermis including all nerve endings hence, the burn site is not painful; subjected to infections and fluid loss; medical intervention involving grafting, fluid, protein and ion replacement are required for healing |
|
|
Term
|
Definition
When skin is young, thick, and full of elasticity it can resist muscle tension and does not develop a grove or crease when a facial muscle is contracted - such as a frown, squint, or a smile. However as we age and our skin becomes thinner, drier, less resilient, it starts to adhere itself to the underlying muscle tissue. So now when we frown the skin gets pulled along with the muscle creating a valley, a line, or a deep wrinkle over time. Botox blocks the transmission of signals from nerves to the muscles, by hindering the production of the neurotransmitter (the chemical which relays the signals). When used for cosmetic purposes this causes the muscle to relax giving it a smoother appearance and greatly reducing the appearance of lines and wrinkles |
|
|
Term
Classification of bones on the basis of shape |
|
Definition
Long bone (humerus),
Short bone (triquetral),
Flat bone (sternum)
Irregular bone (vertebra), left lateral view |
|
|
Term
|
Definition
Spongy bone-like a honeycomb – composed of needle-like structures called TRABECULAE = structural units of spongy bone Compact bone-composed of OSTEONS = structural units of compact bone. |
|
|
Term
|
Definition
Epiphyses = expanded ends of long bones spongy bone surrounded by a thin layer of compact bone Diaphysis = shaft = long axis of a long bone composed of a thick collar of compact bone which surrounds a Medullary Cavity – contains red bone marrow in childhood and yellow bone marrow in adulthood Hematopoiesis, the process by which blood cells and platelets are formed, occurs only in red bone marrow Membranes: Endosteum and Periosteum |
|
|
Term
|
Definition
Endosteum: covers the internal surfaces of bone such as the canals. It contains osteoblasts and osteoclasts Periosteum: is double-layered – composed of the outer fibrous layer and the inner osteogenic layer. The fibrous layer is composed of dense irregular connective tissue The osteogenic layer contains of osteoblasts and osteoclasts. The periosteum is attached to compact bone by tough collagenous fibers called the SHARPEY”S(perforating) FIBERS |
|
|
Term
|
Definition
Osteoblasts: bone-forming cells – secrete bone tissue Osteogenic cells: give rise to osteoblasts Osteocytes: matured osteoblasts Osteoclasts: bone-resorbing cells – destroy bone tissue |
|
|
Term
Microscopic structure of compact bone |
|
Definition
Composed of osteons= structural units of compact bone Each osteon is an elongated cylinder consisting of concentric tubes called LAMELLAE hence, compact bone is also known as Lamellar bone. The collagen fibers in adjacent lamellae run in opposite directions to resist twisting HAVERSIAN CANAL = Central canal – runs in the core of each osteon contains blood vessels and nerves Perforating or Volkmann’s canals – connect blood vessels and nerves between the periosteum and the Haversian canals LACUNAE – shallow cavities in the solid bone matrix that house the osteocytes. CANALICULI – tiny canals that connect lacunae to each other and to the Haversian canal to allow for transfer of substances from the blood vessel in the Haversian canal |
|
|
Term
OSSIFICATION ( Osteogenesis) - Development of the bony skeleton from the embryonic skeleton |
|
Definition
2 forms: PRENATAL AND POSTNATAL Prenatal bone development – occurs before birth; 2 types i) INTRAMEMBRANOUS OSSIFICATION ii)ENDOCHONDRAL OSSIFICATION Intramembranous ossification: develops from FIBROUS CONNECTIVE TISSUE MEMBRANE ( derived directly from mesenchyme) and results in the formation of MEMBRANE BONES = cranial bones and clavicles Note: all membrane bones are flat bones. |
|
|
Term
An ossification center appears in the |
|
Definition
fibrous connective tissue membrane. •Selected centrally located mesenchymal cells cluster and differentiate into osteoblasts, forming an ossification center. Bone matrix (osteoid) is secreted within the fibrous membrane. • Osteoblasts begin to secrete osteoid, which is mineralized within a few days. • Trapped osteoblasts become osteocytes. |
|
|
Term
Intramembranous ossification |
|
Definition
develops from FIBROUS CT MEMBRANE ( derived directly from mesenchyme) and results in the formation of MEMBRANE BONES = cranial bones and clavicles Note: all membrane bones are flat bones |
|
|
Term
Endochondral Ossification |
|
Definition
Derived from HYALINE CARTILAGE produced by chondroblasts; (chondroblasts are derived from mesenchyme) The bones formed from endochondral ossification are called endochondral or cartilage bones = all bones in the body except the cranial bones and the clavicles |
|
|
Term
Endochondral Ossification |
|
Definition
Hyaline cartilage is ossified into bone. After endochondral ossification, hyaline cartilage still persists in two areas in the long bones as the: 1. Articular cartilage – capping the ends of the epiphyses of long bones 2. Epiphyseal plates = at the junctions of the epiphyses and the diaphysis of a long bone |
|
|
Term
|
Definition
Ossification that occurs after birth 2 types: Longitudinal bone growth and Appositional bone growth
Longitudinal bone growth = Linear bone growth increases the length of long bones = height
Appositional bone growth = increases the width/diameter of all bones |
|
|
Term
|
Definition
Involves the EPIPHYSEAL PLATES New hyaline cartilage is added on at the epiphyseal faces of the epihyseal plates New bone tissue is added on at the diaphyseal faces of the epiphyseal plates Results in lengthening of the diaphysis of the long bone = lengthening of the long bone The amount of new hyaline cartilage added on the epiphyseal face = the amount of bone tissue formed on the diaphyseal face hence, the width ( thickness) of the epiphyseal plates does NOT change |
|
|
Term
|
Definition
All bones widen and increase in diameter/thickness via appositional bone growth Sequence of events: Osteoblasts in the osteogenic layer of the periosteum secrete new bone tissue onto the external surface of the bone Osteoclasts in the endosteum slightly resorb bone tissue in the internal surface of the bone Overall, more new bone tissue is added onto the external surface and old bone tissue is slightly resorbed from the internal surface resulting in a thicker but lighter bone. |
|
|
Term
Hormonal Control of Postnatal Bone Growth |
|
Definition
Growth hormone – stimulates hepatocytes to produce Insulin-like growth factors ( IGFs) IGFs stimulate chondroblasts to produce hyaline cartilage on the epiphyseal faces of the epiphyseal plates and bone formation on the diaphyseal faces Sex steroid hormones ( testosterone in the male and the estrogens in the female) synergize with growth hormone to cause “growth spurt” Towards the end of adolescence, the sex steroid hormones antagonize the actions of growth hormone and the epiphyseal plates become ossified = EPIPHYSEAL PLATE CLOSURE – height determined |
|
|
Term
|
Definition
Adult bones constantly undergo bone formation on the periosteal surface and bone resorption on the endosteal surface = Bone Remodeling In healthy adults, the bone density remains constant because Rate of Bone formation = rate of bone resorption If the rate of resorption outpaces the rate of formation = OSTEOPOROSIS Functions of Bone Remodeling: i) To maintain calcium homeostasis ii) To allow for bone repair after fractures |
|
|
Term
Factors that Control Bone Remodeling |
|
Definition
2 factors: Hormonal control and mechanical stress Hormonal Control: Under hypercalcemic conditions, CALCITONIN is released to stimulate osteoblasts to produce bone tissue and stimulate mineralization – uses calcium from blood Under hypocalcemic conditions, PARATHYROID HORMONE (PTH) is released to stimulate osteoclasts to cause bone resorption to release calcium from bones into blood I,25 dihydroxyvitamin D stimulates calcium absorption from the small intestine Mechanical Stress:
+Bones remodel/grow in response to mechanical stresses placed on the bones = WOLFF’S LAW |
|
|
Term
Forms of evidence in support of Wolff’s Law |
|
Definition
Bone attachment sites for active skeletal muscles appear thicker – projections such as trochanters, spines, Bones of the upper limb often used are thicker than the less used limb – bones in the right arm of a right-handed individual are thicker than bones in the left arm and vice versa Long bones are thickest in the middle region of the diaphysis where bending stresses are greatest Bedridden individual not subjected to the stresses of walking or exercises lose bone density Astronauts who spend appreciably amount of time in space (where there’s no gravity and they cannot walk), lose bone density |
|
|
Term
|
Definition
Skeletal muscle tissue striations; long, cylindrical cells called muscle fibers; multinucleate cells Cardiac muscle tissue striations; branching cells with intercalated discs; uninucleate cells Smooth muscle tissue No striations; spindle-shaped cells; uninucleate cells |
|
|
Term
|
Definition
Each muscle fiber ( = skeletal muscle cell) is wrapped in a delicate CT membrane called ENDOMYSIUM Fascicle – consists of a group of endomysium-covered muscle fibers wrapped in a coarse CT membrane called PERIMYSIUM Skeletal muscle – consists of a group of fascicles wrapped in a tough CT membrane called EPIMYSIUM |
|
|
Term
Patterns of Arrangement of Fascicles in skeletal Muscles |
|
Definition
Muscle fibers in a skeletal muscle form bundles called fascicles. The muscle fibers in a single fascicle are parallel, but the organization of fascicles in the skeletal muscle can vary, as can the relationship between the fascicles and the associated tendon. The different patterns of fascicle organization form parallel muscles, convergent muscles, pennate muscles, circular muscles Parallel MusclesIn a parallel muscle, the fascicles are parallel to the long axis of the muscle. Most of the skeletal muscles in the body are parallel muscles. The biceps brachii muscle is a parallel muscle with a central body. When a parallel muscle contracts, it gets shorter and larger in diameter. A skeletal muscle cell can contract until it has shortened by roughly 30-50 percent. Because the fibers in a parallel muscle are parallel to the long axis of the muscle, when the fibers contract together, the entire muscle shortens by the same amount. If the muscle is 10 cm long, the end of the tendon will move 3-5 cm when the muscle contracts. |
|
|
Term
Pattern of Arrangement, continued |
|
Definition
In a convergent muscle, the muscle fibers are spread over a broad area, but all the fibers converge at one common attachment site. The muscle fibers typically spread out, like a fan or a broad triangle, with a tendon at the apex. The pectoralis major muscle is a good example of it. A convergent muscle has versatility, because the stimulation of only one portion of the muscle can change the direction of pull. Then, convergent muscle fibers pull in different directions rather than all pulling in one same direction.Pennate MusclesIn a pennate muscle, the fascicles form a common angle with the tendon. Because the muscle cells pull at an angle, contracting pennate muscles do not move their tendons as far as parallel muscles do. But a pennate muscle contains more muscle fibers--and, as a result, produces more tension--than does a parallel muscle of the same size. If all the muscle fibers are on the same side of the tendon, the pennate muscle is unipennate. More commonly, a pennate muscle has fibers on both sides of the tendon. Such a muscle is called bipennate. The rectus femoris muscle, for example, is bipennate If the tendon branches within a pennate muscle, the muscle is said to be multipennate. The triangular deltoid muscle of the shoulder is multipennate. Circular Muscles also referred to as sphincters the fascicles are arranged in concentric rings; they surround external body openings Source: IFBB.com |
|
|
Term
Simple squamous epithelium |
|
Definition
Description:Single layer of flattened cells with disc-shaped,
function: secretes lubricating substances in serosae |
|
|
Term
Simple cuboidal epithelium |
|
Definition
Description:Single layer of cubelike cells with large, spherical central nuclei,
Function:Secretion and absorption. |
|
|
Term
Simple columnar epithelium |
|
Definition
Description:Single layer of tall cells with round to oval nuclei,
Function:Absorption; secretion of mucus |
|
|
Term
Pseudostratified columnar epithelium |
|
Definition
Description:Single layer of cells ofdiffering heights,
Function:Secretion |
|
|
Term
Stratified squamous epithelium |
|
Definition
Description:Thick membrane composed of several cell layers,
Function:Protects underlying tissues in areas subjected to abrasion |
|
|
Term
Stratified Columnar Epithelium |
|
Definition
Description:at least 2 layers of cells – the apical cells are columnar shaped,
Function:Secretion, Protection |
|
|
Term
Stratified Cuboidal Epithelial Tissue |
|
Definition
Description:at least 2 layers of epithelial cells – apical cells are cuboidal cells
Function:Secretion and protection |
|
|
Term
|
Definition
Description: Resembles both stratified squamous and stratified cuboidal,
Function: Stretches readily and permits distension of urinary organ by contained urine |
|
|
Term
|
Definition
Description:Gel-like matrix with all three fiber types, Function:Wraps and cushions organs |
|
|
Term
|
Definition
Description:closely packed adipocytes,
Function: Provides reserve food fuel; insulates against heat loss; |
|
|
Term
|
Definition
Description:Network of reticular fibers in a typical loose ground substance,
Function:Fibers form a soft internal skeleton (stroma) that supports other cell types including white blood cells, |
|
|
Term
Dense Regular connective tissue |
|
Definition
Description:Primarily parallel collagen fibers,
Function:Attaches muscles to bones or to muscles |
|
|
Term
Dense Irregular Connective Tissue |
|
Definition
Description:Primarily irregularly arranged collagen fibers, Function:Able to withstand tension exerted in many directions |
|
|
Term
Elastic Connective Tissue |
|
Definition
Description:Dense regular CT with high content of Elastic fibers
Function:Exhibit the stretch-recoil properties |
|
|
Term
|
Definition
Description:Amorphous but firm matrix, Function:Supports and reinforces |
|
|
Term
|
Definition
Description: Similar to hyaline cartilage, but more elastic fibers in matrix,
Function:Maintains the shape of a structure while allowing great flexibility |
|
|
Term
|
Definition
Description:thick collagen fibers predominate
Function: Tensile strength with the ability to absorb compressive shock. |
|
|
Term
|
Definition
Description: Hard, calcified matrix containing many collagen fibers
Function:Bone supports and protects |
|
|
Term
|
Definition
Description:Red and white blood cells in a fluid matrix (plasma)
Function:Transport of respiratory gases, nutrients, wastes, and other substances. |
|
|
Term
|
Definition
Description:Neurons are branching cells;
Function:Transmit electrical signals from sensory receptors and to effectors (muscles and glands) which control their activity. |
|
|
Term
|
Definition
Description:Long, cylindrical, multinucleate cells, Function:Voluntary movement; locomotion; |
|
|
Term
|
Definition
Description:Branching, striated,
Function:As it contracts, it propels blood into the circulation; |
|
|
Term
|
Definition
Description:Spindle-shaped cells with central nuclei;Function:Propels substances or objects (foodstuffs, urine, a baby) along internalpassageways |
|
|
Term
Classification of joints: 2 ways |
|
Definition
•Functional Classification - based on amount of movement allowed at the joint:
3 Types:
Synarthrotic joints (Synarthroses)– immovable joints
Amphiarthrotic joints (Amphiarthroses) – slightly movable joints
Diarthrotic joints (Diarthroses ) – freely movable joints
•Structural Classification - based on the material binding the bones at the site, and the absence or the presence of a joints.
3 Types: Fibrous joints, Cartilaginous joints, Synovial joints
|
|
|
Term
3 Structural Classes of Joints |
|
Definition
Fibrous joints-bones joined together by dense CT(type of fibrous CT):joint cavity absent.
3 types:
Sutures– located only in the skull
Functional class of sutures in baby skull: Amphiarthrotic joints
Functional class of sutures in adult skull: Synarthrotic joints
Gomphoses– located only between teeth and bony alveolar sockets
Functional class of gomphoses: Synarthrotic joints
Syndesmoses– bones are connected by ligaments (Synarthrotic joints)
•Cartilaginous Joints– cartilage connects the bones; joint cavity absent
2 types:
Synchondroses – Hyaline cartilage connects bones (Synarthrotic joints)
Symphyses – Fibrocartlage connects bones (Amphiarthrotic joints)
•Synovial Joints – ligaments bind the bones; Joint cavity present
ALL Synovial joints are Diarthrotic joints
Plane joints Pivot joints Saddle joints
Hinge joints Condyloid joints Ball-and-socket |
|
|
Term
|
Definition
•2 types:
•Synchondroses – cartilaginous joints with bones connected by hyaline cartilage. Functional class of synchondroses: Synarthrotic joints
Example: Epiphyseal plates – composed of hyaline cartilage connecting the diaphysis and the epiphyses of a long bone
•Symphyses: cartilaginous joints with bones connected by fibrocartilage
Functional class of symphyses: Amphiarthrotic joints
Examples: Intervertebral disc Pubic symphysis |
|
|
Term
General characteristics of Synovial Joints |
|
Definition
•Articular cartilage – caps the ends of the bones
•Joint Cavity – space that contains synovial fluid which acts like a lubricant to reduce friction
•Articular Capsule – double-layered consists of an
outer fibrous capsule and an inner synovial membrane
• Ligaments that reinforce synovial joints – 3 types of ligaments based on their location in relation to the articular capsule:
Capsular or intrinsic ligaments – located inside the fibrous capsule (example: medial collateral ligaments)
Extracapsular ligaments – located external to the articular capsule
(example: tibial collateral ligaments)
Intracapsular ligaments – located deep to the articular capsule
(example: anterior cruciate ligament (ACL) - a blow to the front of the extended knee tears the ACL , a common sport injury. )
MENISCI – discs of fibrocartilage that extend from the articular capsule into the synovial cavity to improve the fit of a synovial joint which minimizes wear and tear
BURSAE – flattened fibrous sacs that contain synovial fluid to reduce friction where bones, tendons, ligaments and muscles rub together
TENDON SHEATHS – elongated bursae that wrap completely around tendons subjected to a lot of friction; tendon sheaths reduce friction. |
|
|
Term
All Synarthrotic Joints are Diarthrotic Joints |
|
Definition
•Some movements allowed at Synovial joints:
•Gliding: slipping movements
•Flexion: movement that decreases the angle of a joint
•Extension: movement that increases the angle of a joint
•Abduction: movement of a limb AWAY from the midline of the body
•Adduction: movement of a limb TOWARD the midline of the body
•Circumduction: movement of the limb that describes a cone in space
•Rotation: movement of a bone around an axis |
|
|
Term
6 Types of Synovial Joints |
|
Definition
A. Plane joint : articulating surfaces are flat
intercarpals/intertarsals ; Gliding movements allowed
B. Hinge joint: one articular surface is cylindrical and the other surface is a trough; Flexion/extension allowed
Examples: elbow joint; knee joint
C. Pivot joint: one articular surface is round and the other surface is a sleeve or ring; Rotation allowed
Examples: Radioulnar joint
atlanto-axial joint = allows us to move the head side to side to motion “NO”
D. Condyloid joint: one articular surface is oval protrusion and the other surface is an oval depression; Flexion, Extension, Abduction, Adduction, Circumduction allowed
Examples: metacarpophalangeal joints (knuckles); atlanto-occipital joint: allows us to move head up and down to motion “YES”
E. Saddle joint: one articular bone has both convex and concave surfaces and the other articular bone has both concave and convex surfaces ( in reverse); flexion, extension, abduction, adduction, Circumduction allowed
*carpometacarpal joint of the thumb – the only example in the human body
F. Ball-and-socket joint: one articular surface is a spherical head and the other surface is a cuplike socket. ALL movements allowed
shoulder joint; hip joint |
|
|