Chapter 40: Body Surface and Skeletal Systems

Epithelial tissue

Tissue forming protective surfaces and secretions.

Integumentary system

Organ system covering the body, including skin.

Vertebrate skin

Skin structure with epidermis and dermis layers.

Epidermis

Outer skin layer providing protection.

Dermis

Inner skin layer containing connective tissue.

Burns

Tissue damage caused by heat, chemicals, or radiation.

Skin cancers

Malignant growths originating in skin cells.

Skeleton functions

Provides support, protection, and movement.

Animal skeletons

Structures providing support in various organisms.

Vertebrate skeleton divisions

Axial and appendicular skeletons in vertebrates.

Red bone marrow

Produces blood cells in bones.

Yellow bone marrow

Stores fat in long bones.

Structural types of bones

Includes long, short, flat, and irregular bones.

Anatomical regions of long bone

Includes diaphysis, epiphysis, and metaphysis.

Endochondral bone formation

Bone develops from cartilage model.

Intramembranous bone formation

Bone develops directly from connective tissue.

Joints

Connections between bones allowing movement.

Joint movements

Includes flexion, extension, rotation, and abduction.

Cuticle

Protective layer secreted by epithelium in invertebrates.

Nematodes

Roundworms with non-hardening collagen cuticles.

Ecdysis

Process of shedding exoskeleton in invertebrates.

Psuedocoelomate

Organism with a false body cavity.

Earthworms

Segmented worms with flexible, non-hardening cuticles.

Collagen

Protein providing structural support in cuticles.

Arthropods

Invertebrates with hardened exoskeletons made of chitin.

Maundering epithelium

Tissue that secretes new exoskeleton in arthropods.

Mollusks

Soft-bodied invertebrates with external shells.

includes bivalves, nautilus, snails

Syncytial epidermis

Epidermis formed by fused epithelial cells.

Radula

water vascular system

organ used for feeding in mollusks.

human integumentary system functions

physical, biological, and environmental protection, excretion, temperature regulation, cutaneous sensation, metabolic functions, blood reservoir

physical protection of integumentary system

stretching, abrasion, pressure

biological protection of integumentary system

langerhans cells in epidermis (protect from foreign substances)

macrophages in dermis, surface sections: antimicrobial proteins, slightly acidic secretions

protection from environmental factors in the integumentary system

Melanin: UV protection

secretions: prevent polar and ionic molecules from crossing skin - nonpolar covalent substances can cross

excretion of integumentary system

sweat as a cooling system

some nitrogenous, water and salt

temperature regulation of integumentary system

perspiration (process of sweating)

blood vessels

cutaneous sensation

environmental stimuli: pain, touch, vibration

metabolic functions of the integumentary system

vitamin d production: exposure to sun is critical

activation of topical steroids: as absorbed by skin

melanocytes

cells that produce melanin

keratinocytes

produce keratin, resists mechanical stress

precursor to vitamin d

Merkel cells

Cells responsible for light touch sensation, slow adapting

langerhan cells

immune system cells, defense against foreign substances

Papillary layer

Superficial layer of dermis with loose connective tissue.

contain papillae (upward projections/epidermal ridges)

Meissner corpuscles

Receptors for light touch shape and texture in the skin

rapidly adaptive

reticular layer

Deeper layer of the dermis that supplies the skin with oxygen and nutrients

contains dense irregular connective tissue (mainly collagen) used for protection and elastic fibers (tearing causes stretch marks

Pacinian corpuscles

Receptors for deep pressure and vibration.

1st degree burn

superficial burns

Only the epidermis

red, minor pain

no blisters or permanent damage

(regular sunburn)

2nd degree burn

partial thickness burns

epidermis and dermis

blisters, painful, possible scaring

3rd degree burns

full thickness burns

epidermis, dermis, and subcutaneous tissue (hypodermis)

not painful at first (receptors are destroyed), fluid loss, infection

skin grafting and medical intervention

4th degree burn

full-thickness burn extending to muscle or bone

Basal cell carcinoma

Most common skin cancer from keratinocytes.

squamous cell carcinoma

keratinocytes in stratum spinosum

more likely to metastasize to lymph nodes

looks reddish

Malignant melanoma

rarest and deadliest skin cancer involving melanocytes

can metastasize to lymph nodes and blood vessels

Skeletal system functions

structural support

facilitating movement protection of vital organs storage of minerals (calcium and phosphate)

blood cell formation (blood cells in bone marrow)

energy through lipid storage (yellow bone marrow)

Hydrostatic skeleton

Fluid-filled structure providing support and movement.

fluid moves within compartment, constant volume

organism: invertebrates

muscular hydrostat skeleton

tissue fluid

constant volume

organism: invertebrates and vertebrates

exoskeleton

secreted by and covers epithelium

muscle attach to it

organism: invertebrates

Gastrovascular cavity

Fluid-filled cavity aiding in digestion and support.

Contractile proteins

Proteins enabling muscle contraction in organisms.

Epidermal contraction

Outer layer shortening for movement.

Endodermal contraction

Inner layer lengthening for movement.

Composition of exoskeletons

Made of calcium carbonate or chitin.

Continual growth exoskeletons

Secrete calcium carbonate continuously

Cnidarians: anthozoa - hard corals

Mollusks: shell

Molted exoskeletons

Ecdysis process in Ecdysozoa.

cuticle containing chitin

thin, flexible at joints

arthropods

invertebrate endoskeleton

Internal skeleton covered by another tissue (cartilage and/or bone), muscles attach to it and causes skeleton to move when contracts

organism: chordates (notochord or bone) and echinoderms (ossicles - calcified spines and plates between epidermis)

example: poriferans - paprazoans and spicules in mesohyl

Vertebrate endoskeleton

Composed mainly of bone (ossified) and cartilage (chondrichthyes)

Tetrapod skeleton

Four limbs: two forelimbs, two hind limbs

animals: birds, amphibians, reptiles, mammals

Axial skeleton

Central axis of the vertebrate skeleton.

Appendicular skeleton

Limb bones and their connections.

Pectoral girdle

Connects upper limbs to the body.

Pelvic girdle

Connects lower limbs to the body.

Dense bone

Outer hard bone enclosing spongy bone.

Osteon

Interlocking structural unit of dense bone.

osteocytes

mature bone cells

lacunae

small cavities that contain osteocytes

lamella

concentric circles of lacunae

canaliculi

little channels that connect lacunae

haversian canal

central canal, runs lengthwise with blood vessel

Spongy bone

Located inside dense bones and the end of long bones, contains bone marrow.

spongy bone functions

blood cells formed here

structure provides resistance against tree in multiple directions

Trabecular bone

Another name for spongy bone.

Bone marrow types

Yellow for fat, red for blood cell production.

white (fat, used for storing energy) replaces red marrow as you get older

located between trabeculae

Long bone

Includes periosteum, diaphysis, and epiphysis.

longer than wide

short bones

more cuboidal shaped

flat bones

flat like a sandwich

irregular bones

not one shape, lots of projections (vertebrae)

sesamoid bones

unique shaped

patella and hyoid bone

Epiphyseal plate

Growth plate in long bones.

anatomical regions on a long bone

epiphysis: ends

diaphysis: middle of bone

metaphysis: between epiphysis and diaphysis

intramembranous bone formation

bones without synovial joints

develop within connective tissue without a cartilage scaffold first

joints (articulations)

location: junction between two or more bones

function: allow flexibility and movement between most bones

surface protection: bone surfaces coming into contact with one another covered by articular (hyline) cartilage

Synovial joints

encapsulated, fluid filled

reinforced with ligaments

freely moveable movement

Fibrous joints

bones joined by fibrous connective tissue

slightly (amphiarthrosis) or Immovable (synarthrosis) joints, such as sutures

Cartilaginous joints

connected by cartilage

Slightly movable

example: fibrocartilage joints in pelvis, hyaline cartilage on ribs

nonaxial joint

allow slipping or sliding motion not around an axis

joint class = plane joint

uniaxial (hinge) joint

cylindrical projection of one bone fits into a trough-shaped surface on another

motion: only along one axis

ex: hinge (elbow) and pivot (radius and ulna)

biaxial joint

oval surface of one bone fits into complementary depression on another

example: condylar and saddle joints (carpal and metacarpal of thumb)

motion: around two axes

triaxial/multiaxial joints

ball shaped projection of one bone fits into complementary depression on another

example: ball and socket (hip joint)

motion: around three separate axes

flexion

angle less than 180 - gets smaller

extension

angle gets bigger - back to 180

hyperextension

angle past 180