A&P Exam 2 TERMS AND DEFINITIONS

Closed fracture

Fracture that doesn’t break the skin

Open fracture

Fracture in which at least one end of the broken bone tears through the skin; carries a high risk of infection

Transverse fracture

fracture straight across the long axis of bones

Spiral fracture

fracture resulting from twisting forces applied to the bone

Comminuted fracture

Fracture in which the bone is shattered into multiple scattered into multiple fragments, difficult to repair.

Impacted fracture

fracture in which one fragment is driven into the other; usually as a result of a compression

Greenstick fracture

Fracture in which the bone breaks on one side but only bends on the other side; simillar to when a twig is bent.

Oblique fracture

fracture that occurs at an angle that is not 90 degrees

Compression fracture

fracture in which the bone is crushed under the weight it is meant to support

Avulsion fracture

Fracture in which a tendon or ligament pulls off a fragment of bone, often seen in ankle fractures.

Epiphyseal Plate fracture

fracture that involves at least part of the epiphyseal plate; occurs only in children and young adults.

1. Fracture hematoma forms (blood clot)

2. Internal and external calli form (phagocytic cells start cleanup, fibroblasts release collagen, chondrocytes secrete cartilage = soft callous is formed)

3. Cartilage of calli is replaced by trabecular bone (osteoblasts turn the cartilage into spongy bone)

4. Remodeling occurs (spongy bone to normal bone)

Stages in fracture repair

Connective tissue features

• most abundant tissue in the body

• functions as strength, support, and protection

• insulation

• transport substance around body

• degrees of vascularity

• composed primarily of non-living substances

Elements of connective tissue

fibers, cells (cytes; immune cells, blood cells, fat cells, etc.)

Protein fiber types in CT

Collagen, elastic, reticular

Collagen

most common protein in body; ropes of three; high tensile strength; white fibers; stronger than steel cables

Elastic

thing fibers forming branching networks; made of elastin; coiled like a spring; yellow fibers

Reticular

short collagen fibers, has collagen; forms nets; has more give than larger collagen

blasts (cells)

create and send out proteins (create the extracellular matrix)

Cytes

“basic” cells; maintain the matrix

Immune cells

ex. macrophages, lymphocytes, mast cells

Connective tissue (overview)

cells spread out through the matrix, degrees of vascularity, functions are strength, protection, and support

All CT starts as a ____ cell

mesenchyme

Mesenchyme

source of all CT; undifferentiated; star shaped, fluid ground substance, fine protein fibrils

Areolar CT (diagram)

Areolar CT (photo)

Areolar CT characteristics

gel-like matrix, scattered fibrous proteins, most abundant CT

Areolar CT cells

fibroblasts, macrophages, mast cells, and adipocytes

Areolar CT locations

under ET, around organs and capillaries

Areolar CT functions

reservoir for salt and water, diffusion space, universal packing material

Adipose CT

Adipose Tissue characteristics

closely packed cells; chicken wire appearance; packed with lipids that push nucleus to the side; low cell division

adipose tissue functions

energy storage, insulation, supports and protects organs

adipose tissue locations

subcutaneous, surrounds kidneys, mammary glands

Reticular CT

Reticular CT

reticular fibers in web-like nets; fibroblasts
functions: supports soft tissue and small blood vessels; bed for free blood cells

locations: lymph nodes, spleen, and bone marrow

dense regular CT

matrix of parallel fibers, has a direction, more collagen than elastin, mostly fibroblasts
Functions: tensile strength and stretch resistance in ONE direction

Locations: ligaments, tendons

Dense regular CT (photo)

Dense irregular CT (photo)

Dense irregular CT

interwoven fibers, wavy/swirled, fibroblasts
functions: tensile strength and stretch resistance in multiple directions

locations: dermis, fibrous joint capsule

Elastic CT (photo)

Elastic connective tissue

similar to dense regular; slightly wave; elastin instead of collagen

functions: elastic; recoils after stretch
locations: walls of large arteries, walls of bronchial tubes

Cartilage

avascular; chondrocytes widely dispersed; matrix fairly solid; stands up to tension/compression; primarily collagen; 80% water; associated with bone

Hyaline Cartilage (photo)

Hyaline cartilage

matrix appears transparent, chondrocytes in lacunae, chicken wire appearance

functions: rigid/smooth yet flexible, forms embryonic skeleton, allows growth of long bones
locations: articular cartilage, growth plate, costal cartilage, nose, trachea

Elastic cartilage (photo)

Elastic cartilage

similar to hyaline, but contains elastin as well; more visible fibers

functions: flexibility and strength, shape retention
locations: external ear, epiglottis

fibrocartilage (photo)

fibrocartilage

bundles of collagen fibers, chondrocytes in lacuna
functions: absorbs compression forces, tensile strength
locations: intervertebral disks, articular disks (hips, wrist, spine, etc.), pubic symphysis

bone tissue (photo)

bone tissue

highly vascular; osteocytes surrounded by lacuna; matrix

blood cells (photo)

blood

40-45% of volume is cells, fibrous proteins for clotting, mostly fluid
functions: transportation of gases, nutrients, wastes, and hormones
locations:
cardiovascular system

covering/lining membranes

thin sheet of tissue covering a structure or lining a cavity; made of epithelium and underlying CT
3 types: Cutaneous, serous, mucous

cutaneous

epithelial layer of skin

serous membranes

moist membranes in closed cavities; have 2 surfaces and serous fluid in the middle

functions of the skin

protection, temperature regulation, sensation, vitamin d synthesis, blood reservoir, excretion

vasodilate; sweat

when the body is too hot, blood vessels ___ to create ____

vasoconstrict; sweat

when the body is too cold, blood vessels ____ so that the body does not ____

Epidermis

made of ET; has keratinocytes, melanocytes, langerhans cells, and merkel cells

Dermis

made of mostly collagen fibers, has fibroblasts, gel-like ground substance, highly vascularized and innervated

Papillary layer of dermis

Areolar CT, papilla, dermal ridges

reticular layer of dermis

80% of thickness of dermis, strength/stretch/flexibility, thick collagen bundles, dense irregular CT

Hair

Functions: protect from insects, warmth (in animals), guard against physical trauma, heat loss, and sun on the head, eyelashes shield eyes from sun, nose hairs catch and filter large particles and insects

vellus hair

short, fine, unpigmented hair

terminal hair (coarse hair)

longer, pigmented; eyebrows, eyelashes, pubic, facial, chest, armpit hair

nails

heavily keratinized cells

functions: protection

Sebaceous glands

function: produce sebum (oily, lipid rich), waterproofing, antibacterial, softens skin
ducts terminate in hair follicles

Location: not in thick skin, large on face, neck, and upper chest

Acne

plugging of hair follicle by excess oil and keratin leading to infection

Eccrine sweat glands

most common type; secretes 99% water, salts, and merocrine; in dermis; NOT associated with hair follicles

Located: palms, soles, and forehead

function: temperature regulation

Apocrine sweat glands

less abundant, in axillae and anogenital regions; secretes sweat, proteins, and lipids; ASSOCIATED with a hair follicle; larger than eccrine

Functions: protection from bacteria, odor (bacteria degrading secretions/proteins)

Ceruminous glands

modified apocrine gland that produces a thick, waxy secretion; found in the ear canal

Mammary glands

modified sweat gland, produces milk, has immune function and nutritional value

Basal Cell Carcinoma

found in lowest layer of Epithelium; low malignancy; 80% of skin cancers; 99% cure rate

sun exposure, fair skin, being older than 50

risk factors of skin cancer

Squamous cell carcinoma

in stratum spinosum (keratinocytes specifically); rapid growth; 2nd most common; high cure rate if caught early

Malignant melanoma

in melanocytes; high malignancy rate; 5% of skin cancers; 30% survival if already spread far when detected

heat, chemical, electricity, light, radiation

types of burns

Superficial burn

1st degree, involves the epidermis; red, dry, painful skin; nerve endings still intact; may also be swelling

Partial thickness burn

2nd degree, damages dermis and epidermis; intense blistering forms, considerable swelling/reddening, severe pain

Full thickness burn

3rd degree, damages all layers of skin (fat/muscles/bones may also be involved); appears charred black, dry, and white; may not have any pain if nerves are severely damaged

Shock

inability to get enough blood flow to our vital organs

Burn complications

immediate loss of body fluids (blood pressure drops) and risk of infection

Abrasion

open wound where part of the epidermis/dermis is scraped off

Laceration

open wound where there is a clean cut, and likely needs a suture

Puncture Wound

Open wound where something is stabbed into the body

Avulsion

open wound where a chunk is taken out of the skin

Contusion

closed wound where blood vessels are damaged, causing blood to leak beneath the skin surface, which causes bruising.

Sesamoid bone

bone encased in a tendon

Long bone

longer than wide; almost all limb bones (except patella, carpals, and tarsals)

Short bone

Equally broad and long; cube like rounded; carpals, tarsals, sesamoids

Flat bones

thin, flat and usually curved; scapulae, ribs, and cranial bones

Irregular bones

doesn’t fit with the others; vertebrae, os coxa bones

protection, support, blood cell formation, mineral storage

Bone functions

forming a lever for our muscles to pull on

Bones create movement by….

Hematopoiesis

production of blood (happens in bone marrow)

calcium and phosphate

minerals bones store

Spongy bone tissue

location: internal

compact bone tissue

location: external

Cartilage as a bone tissue

always associated with bone;

Hyaline = ends of bones, articular

Fibrocartilage = meniscus, between vertebrae