Human A&P - Exam 2 (Muscular/Skeletal System)

cranial bones

8 (frontal, parietal, temporal, occipital, sphenoid, ethmoid)

facial bones

14, mandible, maxilae, zygomatic, nasal, lacrimal, palatine, inferior nasal conchae, vomer

number of rib pairs in humans

12

true ribs

1-7

false ribs

8-10

floating ribs

11-12

endocrine glands regulating blood calcium

parathyroid glands, thyroid gland

parathyroid gland

PTH, raises blood calcium levels that release from bone

thyroid gland

calcitonin, decreases blood calcium (stores in bone)

endosteum

thin membrane lining inside the bone (medullary cavity/trabeculae), contain bone-forming cells (osteoblasts)

haversian canals

central channels in osteons that contain blood vessels and nerves

lamellae

concentric rings of calcified matrix in compact bone, provides strength and resistance to stress

osteon (haversian system)

perforating canals that run horizontally, connect canals to each other and to blood supply of periosteum

lacunae

little spaces in compact/spongy bone tissue where mature bone reside, surrounded by the bone matrix

vascular

bone tissue (has blood vessels)

cartilage

avascular (no blood vessels; nutrients diffuse slow)

lacunae

small cavities that house osteocytes, found in spongy/compact bone

lamellae

concentric, circumferential, interstitial

concentric lamellae

rings around central canal in osteons

circumferential lamellae

outer layers around entire bone (resist twisting)

interstitial lamellae

remnants of old osteons found between newer osteons

osteocytes

mature bone tissue, found inside lacunae, maintain bone matrix

osteons

structural units of compact bone, made of concentric lamellae around a central canal

trabeculae

thin, lattice beams of spongy bone, contain marrow spaces and resist stress

canaliculi

tiny channels connecting lacunae, allowing nutrient/waste exchange between osteocytes

central/perforating canals

central; run longitudinally in osteons, containing blood vessels/nerves

perforating; run horizontally, connecting central canals to periosteum and each other

sharpy’s fibers

collagen fibers anchoring periosternum to bone, that helps attach tendons/ligaments to bone

osteoids

unmineralized organic bone matrix, secreted by osteoblasts before calcium deposition

muscle cells

referred to as fibers (thin, long, thread like shape)

functions of muscle tissue

movement of body/organs, posture maintenance, stabilization of joints, heat production, circulation, movement of substances

locations of muscle tissue

skeletal (bones), cardiac (heart wall), smooth (walls of hollow organs)

myofibrils

thread-like structures inside muscle fibers that contain sacromeres

myofilaments

actin (thin filaments), myosis (thick filaments)

sacromeres

functional contractile units of myofibrils, repeating segments between Z disc

striations

light/dark banding pattern from sacromeres, found in skeletal & cardiac muscle

peripheral nuclei

nuclei located at edges of muscle fibers, characteristic of skeletal muscle

how to determine if a sacromere is fully contracting

Z discs move closer together, I bands shrink or disappear, H zone disappears, A band stays the same

ATP production in skeletal muscle

creatine phosphate system, anaerobic glycolysis, aerobic respiration

what is the functional unit of skeletal muscle because it is the smallest portion capable of contraction

sacromere

what is the myosin anchoring structure

M line

what is the actin attachment structure

Z disc (Z line)

connective tissue layers in skeletal muscle

epimysium, perimysium, endomysium

epimysium

surrounds entire muscle

perimysium

surrounds fascicles (bundles of fibers)

endomysium

surrounds individual muscle fibers

most ATP producing muscle metabolism

aerobic respiration, produces the most ATP per glucose, requires oxygen, occurs in the mitochondria

atlanto-occipital joint of what lever class

fulcrum (joint between skull/atlas) between effort and load

Ex; nodding yes

bones in axial skeleton

80

bones in appendicular skeleton

126

how many bones in the skeleton

206

mineral component of extraceullar bone matrix

hydroxyapatie, calcium phosphate crystal that harden bone matrix

neurotransmitter for skeletal muscle contraction

acetylcholine (ACh), released at neuromuscular junction that triggers muscle action potential

enzyme that clears action potential to allow relaxation

acetylchonlinesterase (AChE), breaks down acetylcholine in synaptic cleft, stops simulation and allows relaxation

oxygen-binding protein in skeletal muscle

myoglobin, stores oxygen in muscle fibers and supports aerobic respiration

total ATP from one glucose

30-32 ATP per glucose, glycolysis + Krebs cycle + electron transport chain

what are glycosomes

specialized organelles found in certain protozoa (parasitic organisms)

function of glycosomes

contain enzymes for glycolysis and allow ATP production in organisms that compartmentalize glucose metabolism

structural classification

fibrous joints, cartilaginous joints, synovial joints

fibrous joints

dense connective tissue with little to no movement

cartilaginous joints

cartilage that connects bones with slight movement

synovial joints

fluid-filled joint cavity that is freely movable

functional classification

synarthrosis, amphiarthrosis, diathrosis

synarthrosis

immovable

amphiarthrosis

slightly movable

diarthrosis

freely movable

pubic symphysis

structural classification; cartilaginous joint

epiphyseal plate

functional classification; synarthrosis

squamous suture of skull

functional type; synarthrosis

fibrous joint of tooth root to alveolar socket joint

gomphosis

ankylosing spondylitis case study

chronic inflammatory disease, affects spin and sacroiliac joints, causes fusion of vertebrae

• symptoms; back pain and stiffness (worse in morning), reduced spinal flexibility

• imaging shows; joint erosion, spinal erosion

definitive test for ankylosing spondylitis

HLA-B27 genetic testing, x-ray/MRI

combination for skeletal muscle fiber conditions

-70 mV, polarized, relaxed

h-zone of sacromere

central region, where only thick (myosin) filaments are present with no actin overlap

• appearance; relaxed (visible and wide), contracted (shrinks or disappears)

joint classifications

structural (fibrous, cartilaginous, synovial)

functional (sunarthrosis, amphiarthrosis, diathrosis)

elbow and knee classification

diathrotic joints that are freely movable (synovial)

specialized joint between the root of the tooth and the alveolus of the jawbone

gomphosis, fibrous join anchored by periodontal ligament

amphiarthrotic joints composed of a ligament

syndesmoses; bones connected by ligaments

hyaline cartilage where bone growth occurs primarily in long bones

epiphyseal plate

articular discs

fibrocartilage pads that divide a joint cavity

improves stability and shock absorption

• EX: TMJ (jaw joint)

burase

fluid filled sacs

reduce friction between bone and muscle/tendon

• EX: shoulder, knee

menisci

c-shaped fibrocartilage pads

cushion and stabilize joints

• EX: knee (medial/lateral meniscus)

tendon sheaths

elongated burase surrounding tendons

reduce friction in repetitive movement areas

• EX: wrist, ankle

ligaments

dense connective tissue connecting bone to bone

stabilize joints and limit movement

hyaluronic acid is a slippery secretion produced by

synovial membrane; found lining synovial joint capsules, produces fluid components

• function; lubrication + shock absorption

articular cartilage is made of what

hyaline cartilage, covers ends of bones in synovial joints that reduces friction and absorbs shock

fontanels

soft membrane gaps between skull bones in infants

found at junctions of cranial bones in the fetal skull

• allow skull flexibility during birth and rapid brain growth

ossify into cranial sutures (fibrous joints) as the skull matures

ligaments between radium, ulna or tibia, fibula

interosseous membranes, type of syndesmosis (fibrous joint) that connects long bones with a sheet of dense connective tissue; provides stability while allowing slight movement

what are the sutures in the skull

coronal, sagittal, labdoid

F-actin

filamentous actin = double helix of thin actin protein threads

G-actin

globular actin = globular protein units, contains the binding site for myosin heads during muscle contraction

tropomyosin

regulatory protein wrapped around the thin filament strands, covers the G-actin myosin binding sites - muscle stays relaxed until signaled to contract

troponin

small calcium-binding protein attached to tropomyosin and actin, when muscle is signaled to contract, calcium ions released from within muscle fiber bind

channels and receptors

leak channels, gated channels

leak channels

always open, allow flow of ions due to concentration gradient via facilitated diffusion

gated channels

open and close; regulate flow of ions via facilitated diffusion

ligand-mediated channels

open when a water-solube molecule binds to a receptor on the channel

• EX: acetylcholine binding to a skeletal muscle fiber will open sodium ion gated channels and depolarize the cell

fibers

muscle cells

fascicles

bundles of muscle fibers

shaps of muscular tissue

circular, parallel, convergent, pennate, fusiform

principles of muscle nomenclature

location, size, shape, orientation, origin/insertion, number of heads