Week 4- Joints and muscles

Different types of joints

Fibrous(syndesmosis, suture, gomphosis)

Cartilaginous (synchondrosis, symphyses)

Synovial

Components of a synovial joint

articular surface, articular cartilage, articular cavity (joint cavity), joint capsule (bursa), ligaments

Different types of synovial joints

Hinge, Condylar, Ball & socket, plane, saddle, trochoid

Function of ligaments, tendons, and menisci

Ligament- bone to bone

Menisci- fibrocartilaginous disks

Tendons- muscle to bone

Purpose/function of bursae and tendon sheaths

synovial fluid filled, to reduce friction

Stifle joint ligiments

cranial cruciate, caudal cruciate, medial cruciate, lateral cruciate (named for attachment on tibia)

Characteristics of 3 types of muscle

skeletal- striated, multi-nuclear

smooth- non-striated

cardiac-striated, single nucli

Role of ATP in muscle contraction

ATP is required for the reactivation of myosin head (cocking motion)

Aerobic v Anaerobic pathways

aerobic- uses O2 anaerobic does not require O2 less efficent

actin, myosin, z-line

actin is where the myosin binds, myosin is the sperm looking thing that grabs on, z-line is the boundary between sarcomeres

sarcoplasmic reticulum role

calcium storage

calcium in muscle contraction

binds to trponin shaving the shape and moving the cover of the actin

Type I v Type II skeletal muscle fibers

I- slow twitch(fatigue resistant many mitochondria)

II- fast twitch (fatiguable , few mitochondria)

Motor unit

All muscle fibers activated by the same neuron

Nerve stimulate muscle contraction

Ach binds to nicotinic receptor, opens ion channels causing depolarization of membrane (activation) that releases Ca

Basis of muscle contraction

Ca

Origin v insertion

origin- little movement

insertion- high movement

Synergistic v antagonistic muscle groups

synergistic- work together

antagonistic- work against eachother

location of smooth and cardiac muscle

smooth- GI tract

Cardiac- heart

ECG measures:

electrical signals that affect heart

p-wave,QRS complex, T-wave, P-wave to P-wave in ECG

p- depolarization of atria qrs- atria repolarization ventricular depolarization

t- repolarization of ventricles

p to p ecg

autocrine, paracrine, endocrine

a-same cell

p- locally

e- whole body

Major hormone groups: peptides/proteins, amines, steroids, eicosanoids

p- insulin, growth

a- ammonia based(histamine, epi& norepi, dopamine, serotonin)

s- cholesterol back bone (sex hormones+ cortisol)

e- fatty acid base- prostaglandin

Ligand and receptor, intracellular second messengers

ligand- effector (what moves around)

receptor- where the piece fits (don’t move)

intracellular ( they are a secondary response for ligands that can’t enter the cell)

classes of hormones use cell-surface receptors v intracellular receptors

peptide- cell surface receptors

steroid/thyroid- in the cell

feedback loops+-

-when the release of hormone results in conditions that decrease the need for the hormone

+when the release of hormone results in conditions that increase the need for the hormone

major hormone groups

hormones produced by each organ

systemic effects of major hormones