Final Bio 131

excitiation contraction requires what substances

Ca+2 and ATP

steps of excitation-contraction coupling

1-action potential arrival 2-acetylcholine release 3-propagation of action potential 4-calcium release 5-troponin activation 6- cross-bridge cycling 7-relaxation

spastic paralysis

increased tone, upper motor neuron damage

flaccid paralysis

decreased tone, lower motor neuron damage

papillary layer

thin, superfical layer loose CT contains capillaries and sensory neurons

reticular layer

thickest 80% of the dermis, deeper layer contains collagen/elastion fibers, glands, and hair follicles

subcutaneous / hypodermal layer

beneath dermis mostly fat and CT

found in bone not cartilage

blood vessels

lacunae

small spaces housing living cells in both tissues

hypodermis = shock absorber because?

made up od adipost tissue - fatty cushioning, insulation, energy storage

gliding motions of wrist use what joints

plane joint

fibrous joints

bones held together-dense connective tissues- immovable(synarthrosis) example: sutures of skull

cartilaginous joints

bones connected by cartilage- slightly movable amphiarthrosis- examples: intervertebral disc/symphysis

synovial joints

bones r not directly connected- fluid filled cavity - freely movable (diarthrosis) examples: shoulder, knee, hip, elbow

leak channels

always opens- K+ leak channels maintain resting potential

mechanically gated

physical deformation, touch receptors in skin

voltage gated

changes in membrane potential- Na+ channels in action potentials

ligand-gated channels

neurotransmitter binding ACh at nicotinic receptors

nicotinic receptors

type: ionotropic(ligand-gated ion channel)

Action: fast, direct iom flow leading to depolarization

Locations: neuromuscular junction autonomic hanglia adrenal medulla

effect: rapid respinse - muscle contractions

primary neurotransmitter: acetylcholine

nerve fibers from the medial aspect of each eye

cross over to the opposite side of the chiasma

what causes osteoporosis

osteoclasts out pace osteoblasts due to low hormone production of th e ovaries

basal nuclei

initiating protective reflex actions

bipolar neurons are found?

retina of the eye

fibrous joint thats peg in socket

gomphosis

spinocerebellar tracts

carry proprioceptive inputs to the cerebellum

major parasympathetic outlfow from the head is via what nerve

vagus CN10

tropomyosin’s rolw in skeletal muscle

contraction inhibitor - blocks myosin binding sites on actin molecules

simplest to complex forms of life

1. atom

2. molecules

3. cells

4. tissues

5. organs

needle pierce skin in what order

1. corneum

2. granilosum

3. spinosum

4. basale

what is the plasma membrane

phospholipid bilayer surrounding the cell

sequence of muscle contractions

1. motor neuron action potential

2. neurotransmitter release

3. muscle cell action potential

4. release od calcium ions from SR

5. ATP-driven power stroke

6. sliding of myofilaments