lab 7: muscle tissue, nervous tissue, membranes and the integumentary system

3 types of muscle tissue

skeletal, cardiac, smooth

skeletal muscle

A muscle that is attached to the bones of the skeleton and provides the force that moves the bones.

cardiac muscle

Involuntary muscle tissue found only in the heart.

smooth muscle

Involuntary muscle found inside many internal organs of the body

Sacromere

Basic contracting unit of muscle cell consits of actin and myosin filaments

intercelated discs

special region where cells join end to end

central nervous system

brain and spinal cord

peripheral nervous system

the sensory and motor neurons that connect the central nervous system to the rest of the body

Neuron

a nerve cell; the basic building block of the nervous system

cell body

Largest part of a typical neuron; contains the nucleus and much of the cytoplasm

dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

axon

the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

Nissl bodies

Rough endoplasmic reticulum in neuron

Neurofibrils

bundles of neurofilaments that provide support for dendrites and axon

Nodes of Ranvier

Gaps in the myelin sheath to which voltage-gated sodium channels are confined.

myelin sheath

covers the axon of some neurons and helps speed neural impulses

telodendrites

distant branches of the axon

ganglion

A cluster of nerve cell bodies, often of similar function, located in the PNS.

membrane

thin layer of tissue that covers a surface, lines a cavity, or divides a space or organ

mucus membrane

an epithelial tissue that secretes mucus and that lines many body cavities and tubular organs including the gut and respiratory passages.

serous membrane

thin layer of tissue that covers internal body cavities and secretes a fluid that keeps the membrane moist; also called serosa

cutaneous membrane

The skin; composed of epidermal and dermal layers

Epidermis

Outer layer of skin (stratified squamous epithelium)

Dermis

middle layer of skin

Hypodermis (subcutaneous layer)

3rd layer of the skin; Consists of connective tissue which binds the skin to the underlying muscle.

papillary layer

outer layer of the dermis, directly beneath the epidermis

reticular layer

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

dermal papillae

Found in the upper layers of the dermis, they create your fingerprint pattern

Meissner's corpuscles

light touch receptors

Pacinian corpuscles

respond to deep pressure and vibration

sweat glands (sudoriferous glands)

tiny, coiled, tubular structures that emerge through pores on the skin's surface

hair bulb

Lowest part of a hair strand; the thickened, club-shaped structure that forms the lower part of the hair root.

hair shaft

The portion of hair that projects above the epidermis

hair papilla

a peg of connective tissue containing capillaries and nerves

erector pili muscle

muscles that cause hair to stand up when it contracts

sebaceous glands

secrete sebum (oil) into the hair follicles where the hair shafts pass through the dermis

Melanin

A pigment that gives the skin its color

Carotene

the yellow pigment of the skin

tactic discrimination of the skin (blue instrument)

sensitivity of the skin due to the difference in the density of touch receptors in different areas of the body

princess and the pea test

sensitivity to pressure

finger tips - knuckles - chin

adaption to pressure

your touch receptors do not send continuous signals; you get used to the clothes on your skin and cant feel them

relative temperature sense

free nerve endings are responsible for detection of hot and cold temperatures and also extremes of temperature. Temperature sensation is not very accurate

liquid crystal thermography

measures that amount of heat emitted by an area of the body by transforming the temperature into visible signals

arch fingerprint

loop fingerprint

whorl fingerprint

fingerprint function

creates friction to increase the grip of the hand