muscular, skeletal, and integumentary (module 2)

Where is skeletal muscle found?

attached to bones

Where is smooth muscle found?

walls of hollow internal organs (stomach/viscera, GI tract, blood vessels)

Where is cardiac muscle found?

only in the heart

Skeletal muscle

striated, voluntary, multinucleated

Smooth muscle

involuntary, non-striated

cardiac muscle

involuntary, striated

Fascia

sheet of fibrous connective tissue that covers and separates muscle

Epimysium

outermost layer of fascia

Perimysium

an additional layer of connective tissue, surrounds smaller bundles of muscle fibres

Fascicles

bundles of muscle fibers

Endomysium

third layer of connective tissue, surround fascicles

3 ways muscle forms attachments to other structures (other muscle, bone)

1) Tendon attaches muscle to bone

2) Muscle attaches directly to a bone or soft tissue without tendon

3) Flat fascia called aponeurosis connects muscle to muscle or muscle to bone

Aponeurosis

strong, flat fascia that acts as a tendon to attach muscles to bone

Myofibril

long cylindrical structures that make up muscle fibres

Sarcolemma

cell membrane of a muscle fiber

transverse tubules

sarcolemma forms tubes penetrating into the muscle fibre

sarcoplasmic reticulum

Organelle of the muscle fiber that stores calcium

Sarcomere

Contractile units that make up myofibrils, extend from z line to z line and composed of thick filaments (myosin) and thin filaments (actin)

Actin

thin filaments

Myosin

thick filament

myosin heads

structures extending from the myosin filaments

Role of ATP

provides energy for contraction

somatic motor neurons

responsible for reflexes and voluntary control of skeletal muscles

autonomic motor neurons

communicate with visceral organs and involuntary

nicotinic muscle receptor

receptor located at the neuromuscular junction of skeletal muscle

neuromuscular junction

point of contact between a motor neuron and a skeletal muscle cell

myasthenia gravis

a chronic autoimmune disease that affects the neuromuscular junction and produces serious weakness of voluntary muscles

muscle responses

twitch, tetanus, recruitment, tonus

twitch

a quick involuntary cycle of contraction and relaxation

Tetanus

a sustained muscular contraction resulting from a rapid series of nerve impulses

recruitment

contractile force of a muscle, characteristic of the whole muscle

tonus

normal, partially steady state of muscle contraction

How many bones in adulthood

206

Functions of the skeleton

support, protection, movement, mineral storage, blood cell production

Classifications of bones

long, short, flat, irregular

Types of bones

compact bone and spongy bone

Osteocytes

mature bone cells

Diaphysis

shaft of a long bone

Epiphysis

End of a long bone

epiphyseal disc

growth plate

medullary cavity

hollow center of the diaphysis

Periosteum

place for muscles to attach, contains blood supply

articular cartilage

outer surgace of epiphysis, allows easier rotation

Ossification

process of bone formation in fetuses/infants

what is height determined by

genetics and nutrition

osteoclasts

hollows bone from within

osteoblasts

deposits bone into outer surface

resorption

osteoclastic activity

axial skeleton

Portion of the skeletal system that consists of the skull, rib cage, and vertebral column

suture joint

immovable joint

fontanelles

soft spots normally present on the skull of a newborn

vertebral column

spine

thoracic cage

The chest or rib cage.

appendicular skeleton

bones of the appendages

synovial joints

hinge, ball and socket, pivot, saddle, gliding, condyloid

integumentary system

skin, accessory structures (hair, nails), and subcutaneous tissue

functions of integumentary system

mechanical and chemical barrier, protection, immune response, vitamin d synthesis, excretory function, sensory role, body temperature regulation

Skin layers

epidermis, dermis, subcutaneous

Epidermis layers

stratum germinativum, stratum corneum

Where is the dermis located?

between epidermis and subcutaneous layer

function of dermis

gives skin elasticity and allows change and growth. Laced with blood vessels to nourish the epidermis.

what is the subcutaneous layer/hypodermis?

tissue that lies beneath dermis and is highly vascularized

function of hypodermis/subcutaneous layer

fat insulates the body from temperature changes and connective tissue anchors skin to underlying structures

drug delivery systems via the skin

1) hypodermic injections

2) transdermal patches

3) intradermal injections

4) topical applications

what determines our skin colour

genetics, physiology, and pathology

Melanocytes

cells that produce melanin

Melanin

A pigment that gives the skin its color

malfunctions of the melanocytes

albinism, vitiligo, moles, birthmarks

Carotene

yellow-orange pigment of the skin

parts of the nails

free edge, nail body, nail bed, cuticle, nail root, lunula

sebaceous glands

secrete oil and sebum

sudoriferous glands

sweat glands

apocrine glands

present in any area of abundant body hair

eccrine glands

sweat producing glands, critical for temperature regulation

what are some places where eccrine glands can be found?

forehead, back of neck, palms of hands, upper lip, soles of feet

mammary glands

secrete breastmilk

ceruminous glands

secrete ear wax

Functions of fingernails and toenails

to protect delicate tips of fingers and toes from injury

what is most body heat produced by?

muscles, liver, endocrine glands

core temperature

temperature of the inner parts of the body

shell temperature

the temperature of the surface areas of the body

thermoregulation

balance of heat production and heat loss

how is body heat lost

80% of heat lost through skin, 20% lost through lungs and excretory products

Types of heat loss

radiation, conduction, convection, evaporation

Hypothalamus

The thermostat of our bodies in the brain. Determines what temperature your body needs to be and is in charge of heat loss and heat conservation. Loss by dilation of blood vessels (sweating), conservation by shivering and goosebumps.

Normothermia

normal body temperature

Pyrexia

fever

Hyperthermia

Abnormally high body temperature

Hypothermia

abnormally low body temperature

partial thickness burns

first degree, second degree

full thickness burns

third degree

eschar

a thick layer of dead tissue and tissue fluid that develops over a deep burn area, acts as a tourniquet

What are burns classified by?

depth and surface area

Normal body temperature range

97-100 F