Genphyd Exam 1 Flashcards
regulation and internal maintenance of the body
homeostasis
homestasis Greek meaning
homeo = unchanging
stasis = standing
what are the control systems in the body
sensors
control center
communication system
target
gathers data and detect changes
sensors
receives data, send messages, usually the brain
control center
delivers the messages in form of nerve impulses and hormones to target organs, tissues
communication system
organ, tissue or cell that responds to change
targets
what part of the brain is involved to a degree in each of those regulations
hypothalamus
the process in which part of the output of a system is returned to its input to regulate its further output
feedback
the process where the product inhibits the process that creates them
negative feedback loop
the process where the product amplifies the process that creates them
positive feedback loop
occurs when the output of the system acts to oppose changes to the input of the system
negative feedback loop
occurs when the output of the system acts to enhance the changes to the input of the system
positive feedback loop
hormone that contracts the uterus when giving birth
oxytocin
the process of maintaining a steady body temperature
thermoregulation
what happens to the body when the temp is too high
blood vessels dilate, sweating occurs
what happens to the body when the temp is too low
blood vessels constrict, shivering occurs
approx body temp
36-38°C
the process by which an organism regulates the water and electrolytic balance in its body to maintain homeostasis
osmoregulation
organ in charge in gas exchange
lungs
organ in charge in blood glucose
pancreas
hormone produced by beta islets
insulin
hormone produced by alpha islets
glucagon
formation of glycogen
glycogenesis
breakdown of glycogen in the glucose
glycogenolysis
formation of glucose from new sources
gluconeogenesis
special properties of muscular tissue
contractible
extensible
elastic
main functions of muscular tissue
create motion
posture
using sphincters
peristaltic contractions
what are the three types of muscular tissue
skeletal
cardiac
visceral
which of the muscular tissue is the only voluntary muscle
skeletal
which muscular tissue is striated, multi-nucleated, and parallel fibers
skeletal muscle
which muscular tissue is striated, one and central nucleus
cardiac
which muscular tissue has no striations, and one central nucleus
visceral
what is the last muscle that will stop contracting once a person dies
visceral
what muscle contains single fibers that are at least 30cm long
sartorious muscle
what connects muscles to other muscles to form groups of muscles
muscle fascia
the basic functional unit of skeletal muscle fibers
sarcomere
an arrangement of thick and thin filaments sandwiched between two Z discs
sarcomere
where do muscle contractions occur
sarcomeres
myofibrils are built from three groups of proteins, what are they
contractile proteins
regulatory proteins
structural proteins
proteins generate force during contraction
contractile proteins
proteins that help switch the contraction process on and off
regulatory proteins
proteins that keep the thick and thin filaments in proper alignment and link the myofibrils to the sarcolemma and extracellular matrix
structural proteins
proteins of thin filaments
actin
proteins of thick filaments that look like golf clubs bound together
myosin
the third most plentiful protein in muscle; it extends from the Z disc and accounts for much of the elasticity of myofibrils
titan
which neurotransmitter is released at the neuromuscular junction when a motor neuron is activated to initiate muscle movement
acetylcholine (AcCh)
the enzyme that breaks down AcCh after a short period of time
acetylcholine
what is the muscle cell’s plasma membrane region located on the “far side” of the neuromuscular junction (NMJ)?
motor end plate
what gates open during the depolarization phase
Na+
sodium
what gates open during the repolarization phase
K+
potassium
sources of muscle energy
stored ATP
creatine phosphate
aerobic ATP production
anaerobic glucose use
duration of stored ATP
3 seconds
duration of creatine phosphate
12 seconds
duration of anaerobic glucose use
30-40 seconds use
duration of ATP from aerobic cellular respiration
minutes to hours
the amount of O2 repayment required after exercise in skeletal muscle
excess post-exercise oxygen consumption (EPOC)
or
oxygen debt
what term describes the ability of smooth muscle and cardiac muscle to contract on their own without voluntary control
autorhythmic
this requires fewer muscle fibers per neuron
high precision muscles
this requires many muscle fibers per neuron
low precision muscles
give examples of high precision muscles
lateral rectus
inferior rectus
inferior oblique
these are fibers that have a high myoglobin content, more mitochondria, more energy stored, and greater blood supply
red muscle fibers
these fibers have less myoglobin, mitochondria, and blood supply
white muscle fibers
these fibers are the least powerful type and are very fatigue resistant
slow oxidative fibers
these fibers are intermediate in size and are used for walking
fast oxidative-glycolytic fibers
these fibers are suited to intense anaerobic activity of short duration
fast glycolytic fibers
temporary loss of excitability is called?
refractory period
what is recorded when a stimulus causes contraction of a single muscle fiber, measured over a very brief millisecond time frame
twitch
this allows a muscle to accomplish increasing gradations of contractile strength
recruitment
what contraction results in movement
isotonic contractions
what contractions result in no movement
isometric contractions
a type of muscle contraction in which the muscle shorten while generating force
concentric isotonic
a contraction in which muscle tension is less than the resistance (muscle lengthens)
eccentric isotonic
a sudden involuntary contraction of a single muscle within a large group of muscles; usually painless
spasm
involuntary and often painful muscle contractions
cramp
replacement of muscle fibers by excessive amounts of connective tissues
fibrosis (myofibrosis)
hardening of the muscle caused by calcification
myosclerosis
true or false:
Muscle strength at 85 is about half that at age 25
true
this consist of a somatic motor neuron and all the skeletal muscle fibers it stimulates
motor unit
3 fundamental steps done in the nervous system
- sensory
- interpretation (analysis)
- response (reaction)
support cells of neurons
neuroglia
play a major role in support and nutrition of the brain, but they do not manipulate information
neuroglia
subdivisions of the PNS
somatic nervous system (SNS)
autonomic nervous system (ANS)
enteric nervous system (ENS)
neurons that convey information from sensory receptors in the head, body wall and limbs toward the CNS
somatic sensory (afferent)
neurons that conduct impulses away from the CNS towards the skeletal muscles under voluntary control in the periphery
somatic motor (efferent)
small masses of neuronal cell bodies located outside the brain and spinal cord, usually closely associated with cranial and spinal nerves
ganglia
functional unit of the nervous system
neurons
little trees that are the receiving end of the neuron
dendrites
conduct impulses away from the cell body toward another neuron or effector cell
axons
it is where the axon joins the cell body
axon hillock
the beginning of the axon
initial segment
the junction between the axon hillock and the initial segment
trigger zone
the tips of some axon terminals swell into bulb -shaped structures called?
synaptic end bulbs
the site of communication between two neurons or between a neuron and another effector cell is called?
synapse
the gap between the pre and post-synaptic cells
synaptic cleft
what are the tiny membrane-enclosed sacs found in synaptic end bulbs and varicosities of presynaptic neurons called
synaptic vesicles
transport in the axon that conveys axoplasm in one direction only; from the cell body towards the axon terminals
slow axonal transport
transport in axon that occurs in an anterograde and retrograde direction to move materials
fast axonal transport
have several dendrites and only one axon and are located throughout
multipolar neurons
have one main dendrite and one axon
bipolar neurons
neurons that are used to convey the special senses of sight, smell, hearing, and balance
bipolar neurons
contain one process which extends from the body and divides into a central branch that functions as an axon and as a dendritic root
unipolar neuron
4 types of neuroglia in the cns
astrocytes
oligodendrocytes
microglia
ependymal cells
support neurons in the CNS; maintain the chemical environment Ca2+ and K+
astrocytes
produces myelin in cns
oligodendrocytes
participates in the phagocytosis
microglia
form and circulate csf
ependymal cells
2 types of neuroglia in the pns
satellite cells
schwann cells
support neurons in the pns
satellite cells
produce myelin in the pns
schwann cells
process of forming a myelin sheath which insulates and increases nerve impulse speed
myelination
gaps in the myelin sheath
nodes of ranvier
requirements of neuronal regeneration
- located in PNS
- intact cell body
- functional schwann cells
the outer nucleated cytoplasmic layer of the schwann cell, which encloses the myelin sheath
neurolemma
refers to the loss or destruction of myelin sheaths around the axons
demyelination
part of the brain and spinal cord that is formed from aggregations of myelinated axons from many neurons
white matter
part of the brain and spinal cord that is formed from neuronal cell bodies and dendrites
gray matter
an electrical signal used for short-distance communication only
graded potentials
an electrical signal that allow communication over long distances within the body
action potentials
3 types of active, gated channels
ligand-gated
voltage-gated
mechanically-gated
channels that respond to a neurotransmitter and are mainly concentrated at the synapse
ligand-gated
channels that respond to changes in the transmembrane electrical potential and are mainly located along athe neural axon
voltage-gated
channels that respond to mechanical deformation
mechanically-gated
typical value for the RMP
-70mV
any chemical that enhances or stimulates the effects at a given receptor
agonist
a chemical that blocks or diminishes the effects at a given receptor
antagonist
causes a depolarization of the postsynaptic cell, bringing it closer to treshold
excitatory postsynaptic potential
(EPSP)
hyperpolarizes the postsynaptic cell taking it farther from treshold
inhibitory postsynaptic potential
(IPSP)
occurs when postsynaptic potentials arrive near the same location
spatial summation
occurs when postsynaptic potentials arrive close to the same time
temporal summation
