Practice Exam 2 Flashcards
An osteocyte is a _______
bone cell surrounded by matrix
Red bone marrow functions in the formation of _______
red and white blood cells and platelets.
The cells responsible for removing excess bone tissue after the fracture repair process are _______
osteoclasts.
__________ is the process of blood cell formation
Hematopoiesis
Which of the following bones is NOT included within the lower limb
ulna
Which of the following is NOT included in the appendicular skeleton?
vertebral column
Which of the following is included in the pectoral girdle?
Scapula
Cervical vertebrae can be distinguished from other types by the presence of
transverse foramina.
Which of the following bones has an acromion process?
scapula
True or False
The tarsal bones form the wrist.
False
True or False
Synovial fluid moistens and lubricates the cartilaginous surfaces within a joint
True
Articular cartilage is _______
hyaline cartilage
The presence of an epiphyseal plate indicates that _______
the bone is lengthening.
True or False
Most people have 24 ribs.
True
The xiphoid process is part of the _________________
sternum
What is the band of cartilage found in the epiphyses of long bones
epiphyseal plate
What type of cell breaks down the calcified extracellular matrix in developing bones?
osteoclasts
Which bones, or set of bones, support the body’s weight?
the bones of the lower limbs and of the pelvis
What bone articulates with the humerus and carpal bones?
ulna
Which of the following is not part of the axial skeleton?
skull
pelvis
sacrum
hyoid bone
pelvis
The thoracic cage includes which of the following?
twelve pairs of ribs
sternum
Which of the following is not a bone found on a lower limb?
metacarpal
What type of joint is immovable?
sutures
The part of a vertebral bone that supports the human body’s weight is the ______.
body
This type of vertebral bone articulates with a rib.
thoracic vertebrae
There are ______ cervical vertebrae.
7
There are ______ thoracic vertebrae.
12
There are ______ lumbar vertebrae.
5
The anatomical name for the collarbone is the ___________.
clavicle
True or False
A motor neuron and the muscle fibers that it controls constitute a motor unit.
True
True or false
In the initiation of muscle contraction, calcium ions bind to tropomyosin, exposing active sites on actin for cross-bridge formation.
False
The enzyme ATPase occurs in the globular portion of myosin molecules.
True
True Or False
Acetylcholine released by a motor neuron crosses the synaptic cleft and reaches the motor end plate by diffusion.
True
True Or False
ATP is necessary for muscle relaxation.
True
True Or False
The minimal strength of stimulation needed to elicit a muscle contraction is called the threshold stimulus.
True
Myofibrils are composed primarily of
actin and myosin.
A motor unit typically includes how many motor neurons. and muscle fibers
one motor neuron and several muscle fibers
The electrical impulse that triggers a contraction travels deep into a skeletal muscle fiber by means of
transverse tubules
Neurotransmitter molecules are stored in vesicles within
motor neuron endings
Creatine phosphate
supplies energy for the synthesis of ATP
Binding sites on the surface of actin allow the formation of cross-bridges with molecules of
myosin
The threshold stimulus is the
minimum strength of stimulus required to cause muscle fiber contraction to occur
The increase in the number of motor units activated as a result of more intense stimulation is called
recruitment
Activities such as distance swimming and distance running are most likely to stimulate development of
slow fatigue-resistant muscle fibers
Functions of muscle include
the heartbeat
muscle tone
production of heat
moving body parts
The moveable end of a muscle is attached at its
insertion
The muscle primarily responsible for opposing a particular action is called the
antagonist
The enlargement of muscle fibers as a result of exercise is called _______________
hypertrophy
Muscles that assist a prime mover are called _______________
synergists
The less movable end of a skeletal muscle attachment is called the
origin
A mass of dense connective tissue that connects a skeletal muscle to a bone is called a
tendon
True or False
The muscle most responsible for a particular movement is called the prime mover or antagonist
False
Bundles of skeletal muscle fibers are called
fascicles
A skeletal muscle cell is also called a skeletal muscle _____________
fiber
In skeletal muscle, the thick filaments are mainly composed of ___________
myosin
Bundles of actin and myosin filaments form structures called _______
myofibrils
Skeletal muscle cells appear striated because of these parallel bundles
myofibrils
A myofibril may be thought of as many of these joined end-to-end
sarcomeres
The thin filament of skeletal muscle cells is composed mostly of
actin
This structure of a skeletal muscle cell extends from Z line to Z line
saracomere
These are defined as a set of membranous channels that extend inward from the plasma membrane of the muscle cell and pass all the way through the cell.
transverse tubules
The functional connection between a neuron and a muscle cell is called a
neuromuscular junction
The gap that separates a muscle cell membrane from the neuron cell membrane in a neuromuscular junction is called the
synaptic cleft
Neurons communicate with muscle cells by releasing chemicals called ____________
neurotransmitters
How would you describe the region known as the motor end plate?
It is highly folded.
Nuclei and mitochondria are abundant.
It is part of the muscle fiber
It does NOT contains synaptic vesicles
True or False
Troponin, tropomyosin, and actin are all parts of the thin filament
True
The neurotransmitter in skeletal muscle contraction is ___________
acetylcholine
When acetylcholine binds to its receptors in the muscle fiber membrane, the membrane becomes more permeable to
sodium
When an increased concentration of calcium ion is in the sarcoplasm,
actin binding sites are exposed
In skeletal muscle cells, this abundant molecule may be used to transfer energy to ADP to form ATP
creatine phosphate
A single contraction of a muscle fiber in response to a single stimulus is a
twitch
When a muscle is stimulated repeatedly so that it cannot completely relax between contractions, _________ occurs
summation
True or False
If frequency of stimulation is increased, the force of contraction will increase
True
A motor neuron and all the muscle cells it stimulates is called a
motor unit
True or False
Recruitment refers to increasing the number of motor units involved in a muscle contraction
True
True or False
Interneurons are specialized to carry impulses from peripheral receptors into the brain or spinal cord
False
True or False
Nodes of Ranvier connect adjacent neurons
False
True or False
A synapse is the functional connection between two neurons
True
True or False
A nerve is a single neuron
False
True or False
An action potential is an all-or-none response
True
True or False
A neuron may release more than one type of neurotransmitter
True
True or False
Afferent neurons bring sensory information into the central nervous system
True
True or False
Efferent neurons carry impulses from the central nervous system to effectors
True
True or False
Most nerves of the body are mixed nerves
True
True or False
Sensory nerves carry information to effectors
False
True or False
The butterfly shape seen in a cross section of the spinal cord is composed of white matter
False
The simplest nerve pathway in the body is called a(n)
reflex arc
The first component of a reflex arc is a
receptor
The cellular processes of neurons that provide receptive surfaces for input from other neurons are
dendrites
Masses of myelinated nerve fibers appear
white
Which describes the ion concentrations inside and outside of a neuron?
The sodium ion concentration is higher on the outside of the cell and potassium ion concentration is higher on the inside of the cell
During an action potential, depolarization occurs as a result of
sodium ions diffusing to the inside of the cell membrane
Which of the following lists parts of a reflex arc in the correct sequence?
receptor, sensory neuron, interneuron. motor neuron, effector
These convert environmental information into impulses that are conducted to the central nervous system.
sensory receptors
The two major types of cells found in nervous tissue are
neurons and neuroglia
These neuroglia produce the myelin sheath on neurons of the peripheral nervous system
Schwann cells
A branch-like sensory process of a neuron that provides the main receptive surface for communication is called a
dendrite
This neuron process originates as a single structure but may give off many branches
axon
Unmyelinated axons and neuron cell bodies form
gray matter
Gaps in the myelin sheath are called
nodes of Ranvier
Neurons that conduct impulses into the brain or spinal cord are functionally classified as
sensory neurons
Neurons entirely contained within the brain or spinal cord are functionally classified as
interneurons
In a resting neuron, the difference in charges between the outside and inside of the membrane is called a/an
resting potential
When a neuron’s membrane becomes more permeable to sodium, the neuron
depolarizes
When the measured potential of a membrane reaches threshold
sodium rapidly enters the cell
A neuron’s “trigger zone” is the
axon hillock
Impulse conduction is ________ in myelinated nerve fibers
Faster
Faster impulse conduction speeds are possible with _______ axons
thick diameter
Bundles of axons that carry impulses into the brain or spinal cord are
sensory nerves
Bundles of axons that carry impulses from the central nervous system to effectors are
motor nerves
Which list gives the following five parts of a reflex arc in order? (1) central nervous system, (2) effector, (3) motor neuron, (4) receptor, (5) sensory neuron
4, 5, 1, 3, 2
Effectors that are capable of bringing about change in the internal environment include muscles and __________
glands
The cells in the nervous system that fill spaces and give support to neurons are called _____________
neuroglia
Sheaths of myelin produced by ____________ cells often enclose the axons outside of the brain and spinal cord
Schwann
The difference in electrical charge between the inside and outside of a resting nerve cell membrane is called the resting membrane ______________
potential
A nerve impulse consists of a wave of __________ potentials moving along the axon of a neuron
action
