Lab Final Study Guide Flashcards
Skeletal muscle is _______ and ________.
voluntary; striated
Cardiac muscle is _______ , _______, and has _______ _________.
striated, involuntary, intercalated discs
Smooth muscle has _______ and ________.
no striations, involuntary control
Where is skeletal muscle found?
skeletal muscle attached to bone
Where is cardiac muscle located?
walls of the heart
Where is smooth muscle located?
walls of hollow organs
What is the sarcolemma?
plasma membrane of a muscle cell
muscle fiber = ?
muscle cell
muscle cell = ?
muscle fiber
What is a sarcomere?
the functional unit of muscle fibers; is the contractile unit; space between the two z lines
What is the banding pattern?
light and dark bands are created by the arrangement of myofilaments
What are myofilaments?
thick(myosin) filaments and thin(actin) filaments in the sarcomeres
What is the endomysium?
thin connective tissue covering each muscle fiber
What is the perimysium?
fibrous membrane covering bundles of muscle fibers creating a fascicle; bundle of muscle fibers bound together by connective tissue
What is the epimysium?
fibrous connective tissue surrounding many fascicles creating a skeletal muscle; basically the outer covering of the entire skeletal muscle; blend into strong cordlike tendons or into sheetlike aponeurosis
What is aponeurosis?
fibrous or membranous sheet connecting a muscle and the part is moves
What is a tendon?
cord of dense fibrous tissue attaching a muscle to a bone
What is fascia?
layers of fibrous tissue covering and separating muscles
What is the neuromuscular junction(aka myoneural junction)
where the neuron and the muscle fiber interact; the motor axons of the neurons branch into axon terminals
What is a neuron?
a nerve cell
What is a muscle fiber?
muscle cell
What is an axon?
part of the neuron that goes away from the cell body
What is a motor unit, and what does it consist of?
a neuron and all of the muscle fibers it stimulates; consists of synaptic cleft gap between the axon terminal of the neuron and the sarcolemma; axon terminals contain vesicles which have ACh
What is a prime mover or agonist?
muscles that are responsible for producing a particular movement
What is the antagonist?
muscles that oppose or reserve a movement
ex: tricep would be the antagonist when flexing bicep
What is a synergist?
muscles that aid the action of the agonists by reducing undesirable movement
What are fixators or fixation muscles?
specialized synergists that immobilize the origin of the prime mover so that all tension is exerted at the insertion
Ex: the rotator cuff is a fixator in a bicep curl
What are myofibrils?
long parallel muscle fibers that run parallel to each other
What is actin?
thin contractile protein; is bound by myosin to contract muscle
What is myosin?
thick contractile protein; binds to actin to contract muscle
What is a transverse tubule?
an indentation of the sarcolemma into the muscle cell at each junction of the A and I bands
What is the sarcoplasmic reticulum?
the endoplasmic reticulum of the muscle cells
What are the terminal cisterns?
cross channels of the sarcoplasmic reticulum
What is the neuromuscular junction?
the junction between the axon of a motor neuron and a muscle fiber
What is the synaptic cleft?
a small fluid filled gap that separates the neuron and muscle fiber
What is an axon terminal?
a region at the end of each axon branch that is specialized to release packets of chemical neurotransmitters from synaptic vesicles
What are synaptic vesicles?
small intracellular membrane bound vesicles
Describe acetylcholine.
ACh is a neurotransmitter that is released via exocytosis when Ca channels open. ACh diffuses across the synaptic cleft and combines with the receptors on the sarcolemma
What are the two principal cell populations of the nervous system?
neurons and neuroglia/glial cells
Describe neurons
structural units that are highly specialized to transmit nerve impulses from one part of the body to another
Describe neuroglia/glial cells
they branch and protect neurons
List the neuroglia found in the CNS
astrocytes, oligodendrocytes, microglia, & ependymal cells
List the neuroglia found in the PNS
Schwann and satellite cells
Define neurofibrils
cytoskeletal elements
Define chromatoophilic substances
aka the nissil bodies; are rough ER involved in metabolic activities of the cell
What are the two cell body clusters?
nuclei and ganglia
Define nuclei
a cluster of neuron cell bodies found within the CNS
Define ganglia
a cluster of neuron cell bodies found outside the CNS; both the nuclei and ganglia make up gray matter
What are tracts
neuron fibers running through the CNS
What are nerves
neuron fibers running through the PNS
What are the two types of neuron processes?
dendrites and axons
Define dendrites
the receptive regions that bear neurotransmitter receptors
Define axons
generate and conduct impulses
What are collaterals?
branches of axons
What is the axon hillock?
initial axon segment found beside the cell body
What are axon terminals?
the ends of axons which form synaptic clefts with other neurons or effector cells
What is myelin?
fatty material that wraps most long nerves
What is the neurilemma?
the exposed plasma membrane of the Schwann cell
What are the Nodes of Ranvier?
the gaps in the myelin sheath
Axons in the CNS are wrapped by __________?
oligodendrocytes
Axons in the PNS are wrapped by _______ _____?
Schwann cells
Describe unipolar neurons
one very short process that extends from the cell body, most neurons conducting impulses to the CNS are unipolar
Describe bipolar neurons
two processes attached to the cell body, found in the eye, ear, and olfactory mucosa
Describe multipolar neurons
many processes from the cell body, most neurons in the brain and spinal cord
Describe sensory or afferent neurons
carry impulses from sensory receptors in the internal organs only toward CNS
Describe motor or efferent neurons
carry impulses from the CNS to the internal organs, muscles, or glands
Describe association neurons or interneurons
situated between and contribute to pathways that connect sensory and motor neurons
Describe mixed nerves
carry both sensory and motor processes; most nerves in the body
Each nerve fiber is surrounded by _________, a delicate connective tissue sheath.
endoneurium
Bundles of fibers are bound by _________, a coarser connective tissue.
perineurium
Bundles of fascicles are bounded by _________, a white fibrous connective tissue.
epineurium
Describe the autonomic(visceral) reflexes
-are mediated through the Autonomic Nervous System
-the activation of smooth muscle, cardiac muscle, and glands
-regulate body functions such as digestion, elimination, blood pressure, salivation, and sweating
Describe the somatic reflexes
involve stimulation of skeletal muscles by the somatic division of the nervous system
Describe the Reflex Arc Components
- Receptor- the site of stimulus action
- Sensory neuron- transmits afferent impulses to the CNS
- Integration center- consist of one or more neurons
- Motor neuron- conducts efferent impulses from the integration center
- Effector- responds to efferent impulses
What is monosynaptic?
a simple two neurons reflex arc that occurs in a simple patellar or knee jerk reflex
What is polysnaptic?
involves the participation of one or more interneurons in the reflex arc pathway such as the 3-neuron reflex arc
What are the three spinal reflexes?
- stretch reflexes
- crossed extensor reflex
- superficial cord reflexes
Describe the stretch reflex
-maintain posture, balance, and allow locomotion
-stretching of the muscle by tapping its tendon causes the muscle to respond by contracting
-coma patients do not show stretch reflexes
Give two examples of stretch reflexes
- patellar reflex(hit patellar reflex w/ reflex hammer)
- Achilles reflex(hit Achilles tendon with reflex hammer)
Describe the crossed extensor reflex
-more complicated than stretch reflex
-flexor reflex followed by extensor reflex in the opposite limb(ex: someone grabs your right arm, you pull it away and push w/ your left)
-very difficult to produce in the lab bc it is inhibited when expected
Describe the superficial cord reflex
-reflex reaction to pain and temp. changes
What reflex is tested in regard to the superficial cord reflexes, and how is it tested?
the plantar reflex; tested by using a moderately sharp object and stroking the lateral border of the sole of the foot starting at the heel and moving toward the big toe across the ball of foot
What are the two cranial nerve reflexes?
- corneal reflex
- gag reflex
Describe the corneal reflex
blinking of the eyelids in response to something touching the cornea
Describe the gag reflex
gagging in response to touching the roof of the mouth
Describe the parts of the pupillary reflexes
-receptor: retina of the eye
-sensory(afferent) neuron: optic nerve
-motor(efferent) neuron: oculomotor nerve
-effector: smooth muscle of the iris of the eye
-narrowing or dilating of the pupil in response to changes in light
What is the ciliospinal reflex
change in pupil size in response to being touched on the neck
What is the salivary reflex
production of saliva in response to change of pH
Describe the Central Nervous System
consists of the brain and spinal cord, which interprets incoming sensory information and issue instruction based on past experience
Describe the Peripheral Nervous System
consist of cranial and spinal nerves, ganglia, and sensory receptors
What two divisions are in the PNS
sensory(afferent) division & motor(efferent) division
Describe the sensory/afferent division
consists of somatic and visceral sensory nerve fibers, which conduct impulses to the CNS from sensory receptors
Describe the motor/efferent division
consists of motor nerve fibers, which conducts impulses from the CNS to effector organs
Describe the somatic(voluntary) nervous system
consists of somatic motor nerve fibers which conducts impulses from the CNS to skeletal muscles
Describe the autonomic(involuntary) nervous system
consists of visceral motor nerve fibers, which conducts impulse form the CNS to cardiac muscles, smooth muscles and glands
Name the two divisions within the autonomic nervous system
sympathetic and parasympathetic nervous system
Describe the sympathetic division of the autonomic nervous system
mobilizes the body systems during emergency, referred as “fight or flight”
Describe the parasympathetic division
conserves energy and promotes non-emergency functions, referred to as “rest and digest”
Describe gyri
elevated ridges of brain tissue
Describe sulci
shallow grooves in brain tissue
Describe fissures
deep grooves in the brain tissue
The cerebral hemispheres are divides by the _______ _______.
longitudinal fissure
The _____ ____ and ______ _______ are divided by the central sulcus
parietal lobes; frontal lobes
The lateral sulcus separates the ______ _____ and ______ _____.
temporal lobe; parietal lobe
The occipital and parietal lobes are divided by the __________ ______.
parieto-occipital sulcus
Forebrain or prosencephalon which becomes _______ and ___________ in an adult.
cerebrum; diencephalon
Midbrain or mesencephalon which becomes the ________ in an adult
midbrain
Hindbrain or rhombencephalon which becomes the _____, _________, and _________ ________ in an adult.
pons; cerebellum; medulla oblongata
embryonic development the CNS forms the ______ _____ which becomes three major regions, which are ______, ______, _______
neural tube; forebrain; midbrain; hindbrain
What does the primary somatosensory cortex do?
receives impulses from the body’s sensory receptors
What does the somatosensory association area do?
analyzes the incoming impulses
Where is the primary motor area and what is it responsible for
The primary motor area located in the precentral gyrus of the frontal lobe and is responsible for voluntary movement of the skeletal muscles
Where is Broca’s area found and what is it responsible for?
Broca’s area is found in the precentral gyrus of the left hemisphere and is responsible for articulating words
Where is Wernicke’s area found and what is it responsible for?
Wernicke’s area is found in the junction of the parietal and temporal lobe and is responsible for sounding out words
What are the cerebral peduncles?
fiber tracts connecting the pons to the cerebellum
What is the pons?
consists of motor and sensory fiber tracts connecting the brain with lower CNS
What is the medulla oblongata?
houses the vital autonomic centers maintaining homeostasis
What are the structures of the cerebellum?
corpora quadrigemina, superior colliculi, and inferior colliculi
What is the corpus callosum?
major commissure connecting the cerebral hemispheres
What is the fornix?
a band-like fiber tract concerned with olfaction
What is the septum pellucidum?
separates the lateral ventricles of the cerebral hemispheres
What is the thalamus?
two large lobes of gray matter that laterally enclose the third ventricle
What is intermediate mass?
connects the two thalamic lobes and bridges the ventricle
What is the hypothalamus?
the floor and inferolateral wall of the third ventricle; important autonomic center involved in homeostatic balance
What is the infundibulum?
a slender stalk that connects the pineal body to the hypothalamus
What is the pineal gland?
neuroendocrine structure
What is the cerebral aqueduct?
slender canal that connects the third ventricle to the fourth ventricle
What is the vermis?
a midline lobe of the cerebellum?
What is the arbor vitae?
a treelike branching of white matter within the cerebellum, known as the “tree of life”
Describe the meninges
three layers of connective tissue membranes that enclose and protect the brain and spinal cord
What is the dura mater?
the outermost menix composed of two leathery layers, the periosteal and meningeal
What is the arachnoid mater?
web-like middle menix that is partially separated from the dura mater by the subdural space
What is the Pia mater?
the innermost highly vascular menix that clings to the surface of the brain
Meningitis is the
inflammation of the meninges
Inflammation of the brain tissue is
encephalitis
What is cerebrospinal fluid(CSF)?
a watery plasma like composition that constantly circulates around the brain to form a cushion that protects the brain tissue
CSF is constantly being formed in the ______ ______.
choroid plexus
What is the choroid plexus?
small capillary knots hanging from the roofs of the ventricles
What is hydrocephalus?
the accumulation of cerebral spinal fluid causing the gradual enlargement of an infant’s skull
What are the three layers of the meninges?
dura mater, arachnoid mater, and pia mater
Describe referred pain
sensory experience where you feel pain in one area, while it is actually occurring in another area
What test is used to test for nystagmus?
Barany test
