A & P Practice Quizs
What space, found between the vertebral wall and the dura mater, is the area for injecting anesthesia for childbirth? -Subarachnoid space -Subdural space -Epidural space -Epipial space
-Epidural space
An atom has an atomic number of 19 and a mass number of 39. This atom will have _________ neutrons. -19 -39 -58 -20 -30
20
Which of the following activities would stimulate the reticular formation? A warm bath A clock radio coming on in the morning A long lecture in a darkened auditorium Eating a big meal Getting a back rub
A clock radio coming on in the morning
In which of the following situations does a resting membrane potential exist? -A relaxed muscle fiber -A conducting neuron -A stimulated sensory receptor in the skin -A contracting cardiac muscle cell -The eye seeing an image
A relaxed muscle fiber
Which of the following chemical reactions best represents the decomposition of ATP? -ATP + ADP → ATP -ADP + Pi + energy → ATP + H2OH2O -ADP + ADP + ADP → ATP -ATP + H2OH2O → ADP + Pi + energy -ATP + energy → ADP + H2O
ATP + H2OH2O → ADP + Pi + energy
Bone remodeling may occur -as bones grow. -as bones adjust to stress. -as fractures heal. -constantly during a person's lifetime. -All of the choices are correct.
All of the choices are correct.
Normal bone growth requires adequate amounts of certain substance from the diet. Which of the following list three of the dietary needs for normal bone growth? -Potassium, calcium, and vitamin D -Sodium, calcium, and vitamin E -Calcium, phosphate, and vitamin D -Vitamin D, phosphate, and chloride -Vitamin E, vitamin B, and vitamin A
Calcium, phosphate, and vitamin D
Which of these molecules is hydrophobic? -Glucose -Cholesterol -Amino acid -Protein -Disaccharide
Cholesterol
Which of the following situations occurs in electrically excitable cells? -When Na+ channels open, K+ channels close. -The sodium-potassium pump moves Na+ into the cell. -Depolarization causes voltage-gated Na+ channels to open. -Ligand-gated Na+ channels are opened by high extracellular Ca2+ levels. -Proteins tend to diffuse out of the cell.
Depolarization causes voltage-gated Na+ channels to open.
What is the site of longitudinal growth in long bones? -Epiphysis -Medullary cavity -Sharpey's fibers -Epiphyseal plate -Endosteum
Epiphyseal plate
Andrew is in a car accident and fractures his maxilla. To which group of bones does this belong? -Face -Chest cavity -Cervical vertebrae -Pectoral girdle -Cranium
Face
Which structure anchors the thecal sac and conus medullaris to the coccyx? -Filum terminale -Denticulate ligaments -Pia mater -Cauda equina
Filum terminale
A coroner determines the cause of death to be strangulation because this delicate bone is fractured. Which bone is this? -Sphenoid -Clavicle -Vomer -C2 -Hyoid
Hyoid
A person who gets hit on the back of the head might suffer injury to which of these bones? -Temporal -Nasal -Sphenoid -Occipital -Zygomatic
Occipital
Multiple sclerosis is a neurological disorder in which myelin sheaths in the CNS are destroyed. Which of the following neuroglial cells is being damaged in multiple sclerosis? -Astrocyte -Microglia -Oligodendrocyte -Ependymal cell -Schwann cells
Oligodendrocyte
Which of the following is true? -The greater the overlap of actin and myosin, the stronger the contraction. -Overstretching a muscle will increase its tension. -Optimal actin and myosin overlap will produce maximal contraction. -The greatest amount of tension is achieved when actin and myosin do not overlap. -Tension is great when actin and myosin overlap as much as they can.
Optimal actin and myosin overlap will produce maximal contraction.
Which of the following is true during the resting membrane potential? -Sodium ion concentration is greater inside cells. -Negatively charged proteins are more concentrated outside the cell. -A greater concentration of calcium ions is found inside the cell. -Potassium is concentrated primarily inside the cell. -None of these choices reflect what occurs during the resting membrane potential.
Potassium is concentrated primarily inside the cell.
A person lying with his/her face down is said to be in what position? -Supine -Prone -Anatomical -Reverse
Prone
Which of the following bones is part of the axial skeleton? -Clavicle -Rib -Scapula -Hipbone -Radius
Rib
Solution A has a pH of 10, and solution B has a pH of 2. Which of the following statements about these solutions is true? -Solution A has a higher H+ concentration than solution B. -Solution B has a higher H+ concentration than solution A. -Solution A and solution B are both basic. -Solution B is basic. -Solution A is acidic.
Solution B has a higher H+ concentration than solution A.
Which of the following epithelial types is mismatched with its function? -Squamous epithelium - stretching -Simple epithelium - diffusion -Columnar epithelium - secretion -Stratified epithelium - protection -Cuboidal epithelium - absorption
Squamous epithelium - stretching
Which of the following describes the position of the nose? -Inferior to the chin -Superior to the forehead -Posterior to the ears -Lateral to the eyes -Superior to the mouth
Superior to the mouth
Which of the following bones is paired? -Occipital -Vomer -Sphenoid -Mandible -Temporal
Temporal
Which of the following events occurs during the lag phase of a muscle twitch? -Muscle fibers shorten. -Cross-bridges form, move, release, and reform many times. -The action potential is propagated from presynaptic to postsynaptic membrane. -Ca2+ are pumped back into the sarcoplasmic reticulum. -All of these events occur in the lag phase.
The action potential is propagated from presynaptic to postsynaptic membrane.
What is found in the lateral gray horns of the spinal cord? -The cell bodies of somatic motor neurons -The cell bodies of sensory neurons -The cell bodies of autonomic motor neurons -The cell bodies of somatic sensory neurons
The cell bodies of autonomic motor neurons
Which of the following is NOT a property of the myosin head? -They form cross-bridges with the active sites of actin. -They have a hinge region to bend and straighten. -They bind to troponin. -They have ATPase activity. -They bind to ATP.
They bind to troponin.
Which type of epithelial tissue is found in the urinary bladder? -Simple columnar epithelium -Simple cuboidal epithelium -Stratified squamous epithelium -Transitional epithelium -Pseudostratified ciliated columnar epithelium
Transitional epithelium
Which of the following is a synthesis reaction? -Several dipeptide chains are formed from digestion of a long polypeptide chain. -Sucrose is chemically separated to form one molecule of glucose and one molecule of fructose. -ATP is converted to ADP. -Sodium chloride is dissolved in water. -Two amino acids are bonded together to form a dipeptide.
Two amino acids are bonded together to form a dipeptide.
Which nerve has branches that extend to the thoracic and abdominal viscera? -Facial nerve -Vagus nerve -Trigeminal nerve -Glossopharyngeal nerve -Accessory nerve
Vagus nerve
The mesentery is -a double-layered serous membrane that anchors some of the abdominal organs to the body wall. -the serous membrane that covers the lungs. -the serous membrane that lines the abdominal and pelvic cavities. -the space located between the visceral and parietal pleura. -the membrane that lines the pericardial sac.
a double-layered serous membrane that anchors some of the abdominal organs to the body wall.
Dense regular collagenous connective tissue would be found in -a skull bone. -a nerve. -a lymph node. -a ligament. -the brain.
a ligament.
Lesions of the basal nuclei could cause loss of memory. uncontrolled rage. fluent but circular speech. a slight shaking of the hands or head. loss of the sense of smell.
a slight shaking of the hands or head.
The sodium-potassium pump located in the plasma membrane -actively transports sodium into cells. -actively transports water out of cells. -osmotically moves sodium into cells. -moves chlorine out of cells. -actively transports potassium into cells.
actively transports potassium into cells.
The sequence of nucleotides in a messenger RNA molecule is needed to determine the sequence of -amino acids in a protein. -codons in DNA. -nucleotides in the anticodons of tRNA. -nucleotides in a gene. -amino acids in DNA.
amino acids in a protein.
Proteins in cells can act as important buffer systems. If intracellular pH rises, certain _________blank of proteins can _________blank H+ to return pH to normal conditions. -amino acids; donate -nucleotides; donate -amino acids; accept -nucleotides; accept
amino acids; donate
Body odor results from secretions from the __________ sweat glands. -apocrine -eccrine -sebaceous -ceruminous -merocrine
apocrine
Smooth muscle and cardiac muscle are similar in that they both -are under involuntary control. -are striated. -are widely distributed in the body. -have multiple nuclei. -are under voluntary control.
are under involuntary control.
Fibers connecting areas of the cerebral cortex within the same hemisphere are __________ fibers. commissural projection association
association
In a reversible reaction, when the rate of product formation is equal to the rate of reactant formation, the reaction is -at equilibrium. -stopped. -in danger of exploding. -a net synthesis reaction. -a net decomposition reaction.
at equilibrium.
The first cervical vertebrae is the __________. -occipital -axis -clavicle -atlas -mastoid
atlas
When someone taps you on your shoulder, they stimulate the __________ nerve. -axillary -brachial -radial -musculocutaneous -ulnar
axillary
A victim of an automobile accident goes into shock, which results in decreased blood flow. The victim's skin will -become pale. -have a reddish hue. -develop a yellow tint. -become bright red. -not change color.
become pale.
A local anesthetic such as Novocaine decreases membrane permeability to Na+. The use of this anesthetic will -block sensory input into the CNS. -enhance the development of EPSPs. -cause membrane potential to move closer to threshold. -cause Cl− to enter cells instead of Na+. -depolarize the cell.
block sensory input into the CNS.
Spinal nerves C5-T1 make up the __________ plexus. -sacral -lumbar -brachial -cervical -radial
brachial
Vitamin A, a fat-soluble vitamin, would move across the plasma membrane into the cell -by transport with carrier molecules. -by dissolving in the lipid bilayer. -in vesicles. -through vitamin membrane channels. -by active transport.
by dissolving in the lipid bilayer.
Osteoclast activity decreases when _________ levels are elevated. -calcitonin -growth hormone -parathyroid hormone -vitamin D -vitamin C
calcitonin
When an action potential reaches the presynaptic terminal, -calcium ions diffuse into the presynaptic terminal through voltage-gated ion channels. -acetylcholine moves into the presynaptic terminal. -a local potential is generated in the presynaptic terminal. -ligand-gated ion channels in the presynaptic terminal are opened. -nothing else happens.
calcium ions diffuse into the presynaptic terminal through
Lipids -comprise the genetic material of cells. -yield little energy per unit of weight. -are all water soluble. -can insulate and help prevent heat loss. -function as enzymes.
can insulate and help prevent heat loss.
A passageway connecting neighboring osteocytes in an osteon is a __________. -canaliculus -lacuna -osteocanal -lamella -central canal
canaliculus
Neurotransmitters -stimulate presynaptic terminals. -remain in the synaptic cleft for long periods of time. -bind irreversibly to the receptor molecules of the postsynaptic membrane. -cause the production of action potentials in the postsynaptic membrane. -do not affect membrane channels in the postsynaptic membrane.
cause the production of action potentials in the postsynaptic membrane.
Protein synthesis in neurons occurs in __________. -axons -dendrites -cell bodies or soma -presynaptic terminals -nodes of Ranvier
cell bodies or soma
The pectoral region is the -area in front of the elbow. -chest area. -lower back. -bottom of foot. -forearm.
chest area.
Intervertebral discs exhibit a great deal of strength because of the presence of thick bundles of _________. -hydroxyapatite -collagen -elastin -calcium -proteoglycan
collagen
T tubules -provide nutrients to the muscle fiber. -generate new muscle fibers. -conduct action potentials deep into the muscle fiber. -release acetylcholine. -store calcium ions.
conduct action potentials deep into the muscle fiber.
The sensory (afferent) division of the peripheral nervous system -transmits action potentials to sensory organs. -conveys action potentials to the CNS. -stimulates glands to release hormones. -stimulates muscle contractions. -does not involve sensory receptors.
conveys action potentials to the CNS.
Enzymes are proteins that increase the rate of chemical reactions by -adjusting the temperature of the reaction. -increasing the concentration of the reactants. -decreasing the activation energy of the reaction. -increasing the activation energy of the reaction.
decreasing the activation energy of the reaction.
The fact that the right side of the brain controls the left side of the body is explained by the -division of the cerebrum into two hemispheres. -division of the cerebellum into two hemispheres. -decussation of the pyramids in the medulla. -need for contra-lateral control of body function. -brainstem being below the midbrain.
decussation of the pyramids in the medulla.
Stretch marks develop on the abdomen of pregnant women because of stretching and rupture of the __________. -melanocytes -stratum corneum -subcutaneous tissue -dermis -epidermis
dermis
The pyramids of the medulla contain __________. -ascending motor tracts -descending motor tracts -ascending sensory tracts -descending sensory tracts -None of the choices are correct
descending motor tracts
Receptor-mediated endocytosis -occurs if oxygen is available. -is a type of passive transport. -exhibits specificity. -moves materials out of the cell. -does not need ATP; the receptors supply the energy.
exhibits specificity.
A patient in a skiing accident is told that the lateral side of the ankle joint has been crushed. The bone that has been injured is the __________. -femur -tibia -fibula -calcaneus -talus
fibula
A neuron is receiving a stimulus which gets stronger and stronger. The result is -amplitude of the action potential increases. -duration of the action potential increases. -frequency of occurrence of action potentials increases. -resonance of action potentials increases. -height of the action potentials increases.
frequency of occurrence of action potentials increases.
Cell bodies of the peripheral nervous system are located in -ganglia. -Schwann cells. -the motor division. -the sensory division. -nerves.
ganglia.
Membrane-bound receptors -have no effect on the cell. -are small, lipid soluble molecules. -do not exhibit specificity. -have their receptor sites on the outer surface of the plasma membrane. -can interact with DNA in the nucleus.
have their receptor sites on the outer surface of the plasma membrane.
The proper sequence of events in bone repair is -callus ossification, callus formation, remodeling of bone, hematoma formation. -hematoma formation, callus formation, callus ossification, remodeling of bone. -remodeling of bone, callus ossification, hematoma formation, callus formation. -hematoma formation, callus ossification, callus formation, remodeling of bone. -callus formation, hematoma formation, callus ossification, remodeling of bone.
hematoma formation, callus formation, callus ossification, remodeling of bone.
The compression (weight-bearing) strength of bone matrix is due to the presence of __________. -collagenase -bone marrow -elastin fibers -hydroxyapatite crystals -collagen fibers
hydroxyapatite crystals
Mr. Miller has been hospitalized for the flu. The flu virus increases membrane permeability to K+. You would expect his cells to __________. -depolarize -repolarize -isopolarize -hyperpolarize -hypopolarize
hyperpolarize
Anna has an eating disorder along with intense thirst and wildly varying body temperatures, which means she may have a dysfunction of the __________. pons medulla thalamus hypothalamus brainstem
hypothalamus
Parallel curving ridges of dermis that shape the overlying epidermis into friction ridges -tend to make the surface smooth. -are associated with thin skin. -decrease friction on surfaces where they are located. -improve the grip of the hands. -are caused by the pattern of the reticular layer of the dermis.
improve the grip of the hands.
Curare blocks acetylcholine receptors at the motor end plate. This would result in -increased stimulation of the muscle. -more acetylcholinesterase production. -lack of Ca2+ uptake by the muscle fiber. -inability of the muscle fiber to respond to nervous stimulation. -sustained contraction of the muscle.
inability of the muscle fiber to respond to nervous stimulation.
Microvilli -increase the surface area of the cell. -are extensions of the lysosomal membrane. -move the cell. -function to make the cell mobile. -are supported by microtubules.
increase the surface area of the cell.
Local hyperpolarization in a synapse is called a/an __________. -excitatory postsynaptic potential -resting membrane potential -inhibitory postsynaptic potential -gap junction potential -action potential
inhibitory postsynaptic potential
The site where spinal nerves exit the vertebral column is the __________. -intervertebral disk -vertebral foramen -lamina -intervertebral foramen -spinous process
intervertebral foramen
The corpus callosum consists of a broad band of gray matter. is found at the base of the transverse fissure. is a band of commissural fibers that connects the right cerebral hemisphere to the left cerebral hemisphere. connects the frontal lobe to the occipital lobe. connects the frontal lobe to the parietal lobe.
is a band of commissural fibers that connects the right cerebral hemisphere to the left cerebral hemisphere.
A neuromodulator -acts as a neurotransmitter. -inactivates neurotransmitters. -is a receptor site for a neurotransmitter. -has no influence on the amount of neurotransmitter released. -is a substance released from neurons that influences the sensitivity of neurons to neurotransmitters.
is a substance released from neurons that influences the sensitivity of neurons to neurotransmitters.
The conus medullaris -anchors the spinal cord to the coccyx. -is a tapered, cone like region immediately inferior to the lumbar enlargement. -marks the exit of nerves to the upper extremity. -is located adjacent to the foramen magnum. -is inferior to the cauda equina.
is a tapered, cone like region immediately inferior to the lumbar enlargement.
Thick skin -has fewer layers of cells in the stratum corneum than thin skin. -is found in areas subject to pressure or friction, such as the palms. -is determined by the thickness of the dermis. -has three different epidermal strata. -is found covering most of the body.
is found in areas subject to pressure or friction, such as the palms.
Delicate unpigmented hairs that cover the fetus in early development are called __________ hairs. -vellus -secondary -lanugo -primary -terminal
lanugo
The thumb is ________ to the index finger. -distal -lateral -medial -proximal -superficial
lateral
The medullary cavity is -filled with fibrocartilage and elastin fibers. -empty in adult bones. -the site where osteoblasts are found. -lined with endosteum. -dead space in the bone.
lined with endosteum.
Reticular tissue is found in -nervous tissue. -muscles. -long bones. -lymphatic organs. -the intestinal lining.
lymphatic organs.
A patient with a traumatic head injury may exhibit vomiting as a result of irritation of nuclei in the __________. -pons -cerebellum -medulla oblongata -corpora quadrigemina -midbrain
medulla oblongata
In general, water-soluble molecules diffuse through the _________; and lipid-soluble molecules diffuse through the _________. -membrane channels; membrane channels -membrane channels; lipid bilayer -lipid bilayer; membrane channels -lipid bilayer; lipid bilayer -None of the choices are correct.
membrane channels; lipid bilayer
Stratified epithelium consists of -multiple layers of cells. -a single layer of cells. -a single layer of cells that changes shape when the tissue is stretched. -a multiple layer of cells that appears to change shape when the tissue is stretched. -None of the choices are correct.
multiple layers of cells.
The motor neurons responsible for making a fist are __________. -tripolar -bipolar -multipolar -pseudo-unipolar -None of the choices are correct.
multipolar
In excitation-contraction coupling, -Ca2+ must bind with myosin to expose active sites on actin. -myosin heads bind to exposed active sites on actin. -cross-bridges form between myosin heads and Ca2+. -movement of the troponin-tropomyosin complex causes actin myofilaments to slide. -ATP binds to actin myofilaments.
myosin heads bind to exposed active sites on actin.
The umbilical region is commonly known as the _________. -groin -buttock -breastbone -upper arm -naval
naval
If you cut bundles of axons and their myelin sheaths in the PNS, you cut __________. -ganglia -nuclei -nerves -gray matter -nerve tracts
nerves
In the appositional growth of cartilage, -new chondrocytes and new matrix are added on the outside of the tissue. -chondroblasts within the tissue proliferate and add more matrix from the inside. -osteoblasts replace the chondroblasts. -the cartilage is replaced with another kind of connective tissue. -the tissue becomes vascularized in order to grow.
new chondrocytes and new matrix are added on the outside of the tissue.
In the CNS, clusters of gray matter containing cell bodies are called __________. -nuclei -pyramids -tracts -peduncles -ganglia
nuclei
Sam adjusts solution A to increase its acidity. This means that the -pH of the solution has increased. -number of hydrogen ions in the solution has increased. -number of hydrogen ions in the solution has decreased. -solution will now accept more protons. -solution is closer to neutrality.
number of hydrogen ions in the solution has increased.
In the process of diffusion, net movement of substances is always from a region -outside the cell to a region inside the cell. -inside the cell to a region outside the cell. -of lower concentration to a region of higher concentration. -of higher concentration to a region of lower concentration. -None of the choices are correct.
of higher concentration to a region of lower concentration.
The ventral root of a spinal nerve contains __________. -only sensory fibers -only motor fibers -only afferent fibers -both sensory and motor fibers -a ganglion
only motor fibers
Certain cells in the liver ingest bacteria and debris from damaged cells by a process called _________. -biocytosis -exocytosis -diffusion -phagocytosis -pinocytosis
phagocytosis
An investigator who conducts an experiment to determine how changes in pH affect the function of enzymes on digestion is most likely to be a/an _________. -neurologist -anatomist -engineer -physiologist -histologist
physiologist
Important functions of the skeletal system include -regulation of acid-base balance. -protection of the brain and soft organs. -storage of water. -integration of other systems. -production of Vitamin E.
protection of the brain and soft organs.
A decrease in the number of voltage-gated Ca2+ ion channels in the presynaptic terminal would -enhance transmission across the synapse. -reduce or inhibit transmission across the synapse. -have no effect on transmission across the synapse. -alter receptors on the postsynaptic membrane. -increase exocytosis.
reduce or inhibit transmission across the synapse.
The integumentary system -regulates body temperature. -breaks down food into small particles for absorption. -controls intellectual functions. -produces body movements. -coordinates and integrates body function.
regulates body temperature.
In a negative feedback mechanism, the response of the effector -reverses the original stimulus. -enhances the original stimulus. -has no effect on the original stimulus. -is usually damaging to the body. -creates a cycle that leads away from homeostasis.
reverses the original stimulus
Epithelium that is primarily secretory in function would most likely be -stratified squamous. -keratinized columnar. -simple squamous. -simple cuboidal. -transitional.
simple cuboidal.
Movement of food through the digestive tract results from the action of _________blank muscle. -striated -skeletal -voluntary -smooth -cardiac
smooth
The anterior boundary of the "rib cage" is/are the __________. -ribs -sternum -costal cartilages -thoracic vertebrae -skin
sternum
Glycogen is the -sugar found in RNA. -nondigestible plant polysaccharide. -storage carbohydrate in plants. -storage carbohydrate in animals. -major nutrient for most body cells.
storage carbohydrate in animals.
An epithelial tissue has multiple layers, flat and irregular cell shape, dead outer layers of cells, and keratin present in some cells. This is -simple cuboidal epithelium. -pseudostratified keratinized squamous epithelium. -moist stratified squamous epithelium. -stratified keratinized squamous epithelium. -simple transitional epithelium.
stratified keratinized squamous epithelium.
Endomysium is a delicate network of loose connective tissue that -surrounds each muscle fiber. -forms a sheath around a fascicle. -is composed of elastic fibers. -separates individual muscles. -penetrates muscle fibers.
surrounds each muscle fiber.
A person who has cerebrospinal fluid draining from the ear probably has a fracture of the __________ bone. -occipital -parietal -zygomatic -temporal -frontal
temporal
Most sensory input that ascends through the spinal cord and brainstem projects to the __________. pineal gland hypothalamus thalamus mammillary bodies subthalamus
thalamus
The limbic system involves various neural connections between __________. the medulla and pons the pons and cerebellum the cerebrum and diencephalon the diencephalon and midbrain the cerebrum and midbrain
the cerebrum and diencephalon
The parietal pericardium is -a double-layered serous membrane that anchors some of the abdominal organs to the body wall. -the serous membrane that covers the lungs. -the serous membrane that lines the abdominal and pelvic cavities. -the space located between the visceral and parietal pleura. -the membrane that lines the pericardial sac.
the membrane that lines the pericardial sac.
Excitation-contraction coupling begins with -the depolarization at the T tubules. -the production of an action potential in the sarcolemma. -the release of the cross-bridge. -the release of Ca2+ from the sarcoplasmic reticulum.
the production of an action potential in the sarcolemma.
The various types of epithelium are classified by -the number of cell layers and size of the cells. -the size and location of cells. -the shape of cells and number of cell layers. -the size and shape of cells. -function and size of cells.
the shape of cells and number of cell layers.
The ribs articulate with the __________ vertebrae. -sacral -lumbar -thoracic -cervical -coccygeal
thoracic
Maggie has her wisdom teeth removed, and later has difficulty with chewing and cannot feel sensations to the side of her face. This is likely caused by the numbing of the __________ nerve. vagus trochlear hypoglossal trigeminal vestibulocochlear
trigeminal
The brachial region is commonly known as the _________. -groin -buttock -breastbone -upper arm -naval
upper arm
A reflex that protects limbs by removing them from painful stimuli is the __________ reflex. -stretch -crossed extensor -Golgi tendon -alternating -withdrawal
withdrawal
Getting a kiss on the cheek means the __________ bone is involved. -frontal -sphenoid -ethmoid -zygomatic -maxilla
zygomatic
A group of cells was treated with a proteolytic (protein-digesting) enzyme. Which of the following processes would be least affected by this treatment? -Secondary active transport -Sodium-potassium exchange pump -Use of carrier molecules in facilitated diffusion -Diffusion of lipid-soluble molecules through the plasma membrane -Diffusion of Na+ through membrane channels
Diffusion of lipid-soluble molecules through the plasma membrane
Which of the following statements regarding glial cells is false? -Glial cells serve as the major supporting tissue in the CNS. -Glial cells form part of the blood-brain barrier. -Glial cells produce action potentials for skeletal muscles. -Glial cells form myelin sheaths around some axons. -Glial cells produce cerebrospinal fluid.
Glial cells produce action potentials for skeletal muscles.
If you compare a cell with a manufacturing plant that exports goods, the cell's _________blank could be compared to the manufacturing plant's shipping department. -ribosome -lysosome -endoplasmic reticulum -Golgi apparatus -nucleus
Golgi apparatus
Sam is curling very heavy weights and suddenly drops them. Which reflex forced this action by Sam to prevent tendon damage? -Muscle spindle reflex -Golgi tendon reflex -Gamma motor reflex -Withdrawal reflex -Alpha motor neuron reflex
Golgi tendon reflex
Which portion of a reflex arc is most likely to be located entirely within the central nervous system? -Sensory neuron -Motor neuron -Effector -Interneuron -Sensory receptor
Interneuron
Which statement is true about the dermis? -It does not contain connective tissue. -It functions as padding and insulation. -It is divided into three distinct layers. -It is responsible for most of the skin's structural strength. -It contains no blood vessels.
It is responsible for most of the skin's structural strength.
Which of the following is found inferior to the maxilla and has a posterior articulation with the temporal bone? -Parietal -Zygomatic -Mandible -Sphenoid -Palatine bone
Mandible
Which of the following statements concerning epithelial tissue is false? -Secretory epithelial cells are usually cuboidal or columnar in shape. -Columnar epithelial cells promote diffusion. -Cuboidal epithelium is found in areas where absorption occurs. -The movement of materials through epithelium is enhanced by simple squamous epithelium. -Stratified epithelium is adapted for a protective role.
Columnar epithelial cells promote diffusion.
Which of the following is NOT a function of connective tissue? -Storage -Insulation -Contraction -Support -Transport
Contraction
Which of the following is NOT a function of the cerebellum? Coordinate control of voluntary movements Help in the maintenance of muscle tone Control the heart rate Control skeletal muscles to maintain balance Control of posture, locomotion, and fine motor coordination
Control the heart rate
Which of the following activities is NOT associated with the cerebrum? Interpreting smell and taste Controlling the autonomic nervous system Initiating voluntary movements Making moral judgments Writing poetry
Controlling the autonomic nervous system
The endoneurium -surrounds nerve cell bodies. -surrounds individual axons and their Schwann cells. -bundles axons into fascicles. -bundles fascicles into nerves. -surrounds nerve tracts in the spinal cord.
surrounds individual axons and their Schwann cells.
The type of cell connection that serves as a permeability barrier is a _________. -intercalated disc -hemidesmosome -desmosome -tight junction -gap junction
tight junction
Those ribs that attach directly to the sternum are referred to as __________ ribs. -false -vertebral -true -vertebrochondral -floating
true
A symporter will transport _________blank across the plasma membrane. -different ions or molecules in opposite directions -two different ions or molecules in the same direction -two of the same ions or molecules in opposite directions -two of the same ions or molecules in the same direction -one specific ion or molecule
two different ions or molecules in the same direction
Cerebrospinal fluid is formed by tissue in the walls and roofs of the __________. subarachnoid space dural sinuses fissure of Sylvius ventricles of the brain subdural space
ventricles of the brain
When a sperm cell comes into contact with an egg cell, there is a change in the electrical charge across the plasma membrane and various channel proteins close. These channels would be called _________blank channels. -chemical-gated -voltage-gated -open-gated -ligand-gated -nongated ion
voltage-gated
Acetylcholine binds to a membrane bound receptor and causes ligand-gated sodium channels to open and results in -hyperpolarization. -depolarization. -hypoplarization. -no change in membrane potential. -There is not enough information to predict the outcome.
depolarization
The central sulcus separates the __________. two parietal lobes frontal and parietal lobes occipital and temporal lobes temporal and frontal lobes parietal and occipital lobes
frontal and parietal lobes
If the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience complete loss of __________. -sensation -movement -sensation and movement -pain -None of the choices are correct.
movement
Phospholipids have a hydrophilic end which is -nonpolar and not water soluble. -polar and not water soluble. -polar and water soluble. -nonpolar and water soluble.
polar and water soluble.
Skeletal muscle fibers -possess striations. -can contract but are not extensible or excitable. -do not require nerve innervation to contract. -increase dramatically in number after birth. -are found in the walls of the stomach.
possess striations.
Nerve cells generate electrical signals in response to changes in the environment. This is an example of _________. -respiration -digestion -movement -filtration -responsiveness
responsiveness
Spinal nerves exiting the spinal cord from the level of L4 to S4 form the __________ plexus. -lumbar -femoral -sacral -pelvic -brachial
sacral
A vertical plane that separates the body into right and left portions is called a _________blank plane. -sagittal -transverse -frontal -horizontal -coronal
sagittal
Which portion of the brainstem is continuous with the spinal cord? -Medulla oblongata -Midbrain -Pons -Thalamus -Cerebral peduncles
Medulla oblongata
Which of the following statements accurately describes lipids? -Lipids tend to be water soluble. -Lipids are an important component of plasma membranes. -Lipids serve as buffers. -Lipids tend to be polarized. -Lipids are the building blocks of carbohydrates.
Lipids are an important component of plasma membranes.
Bob was completely bald on the top of his head by the time he was 35 years of age. Bob noticed he produced abundant sweat on his head when he exercised. He also noticed that his scalp was no longer oily. Which of the following changes account for the observations? (1) He has fewer functional hair follicles now. (2) He has fewer functional sebaceous glands now. (3) He has fewer merocrine sweat glands now. (4) He has fewer apocrine sweat glands now. 1, 2 1, 2, 4 1, 2, 3, 4 1, 3, 4 1, 2, 3
1, 2
The muscles of the back contract to straighten so that you sit at a more erect posture and subsequently the muscles are suddenly stretched as you nod off. Which of the following best represents the sequence of events when you start to nod off? (1) Muscles of the back are stretched. (2) The muscle spindle is stretched.(3) Action potentials in sensory neurons of the muscle spindles increase. (4) Action potentials in alpha motor neurons of skeletal muscle fibers increase. (5) Skeletal muscle of the back contract. 1, 2, 3, 4, 5 1, 5, 2, 3, 4 1, 5, 3, 2, 4 5, 2, 3, 4, 1 4, 5, 3, 2, 1
1, 2, 3, 4, 5
A tissue has the following characteristics: free surface, single layer of cells, cells are narrow and tall, microvilli, many mitochondria, goblet cells. Which of the following is most consistent with those observations? (1) Active transport (2) Epithelium (3) Simple epithelium (4) Columnar epithelium (5) Cuboidal epithelium (6) Squamous epithelium (7) Secretion by exocytosis (8) Movement of mucous across its surface 1, 2, 3, 5, 7 1, 2, 3, 4, 8 2, 3, 4, 8 2, 3, 4, 7 1, 2, 3, 4, 7
1, 2, 3, 4, 7
Plasma membrane phospholipids -have nonpolar fatty acid tails. -form a bilayer. -have polar phosphate heads. -create a selectively permeable barrier. -All of the choices are correct.
All of the choices are correct.
Reflexes function in -removing the body from painful stimuli. -keeping the body from falling. -maintaining blood pressure. -maintaining blood CO2 levels. -All of the choices are correct.
All of the choices are correct.
Which of the following statements correctly describes ATP? -Can be synthesized from ADP -Stores and releases energy in the cell -Is associated with a reversible reaction -Is associated with anabolism and catabolism -All of the choices are correct.
All of the choices are correct.
A researcher discovered a sensory receptor that detects decreasing oxygen concentrations in the blood. According to the principles of negative feedback, it is likely that stimulation of this sensory receptor will produce which of the following types of responses? -A decrease in heart rate -An increase in the respiratory rate -An increase in physical activity -Unconsciousness -Both a decrease in heart rate and an increase in the respiratory rate will occur.
An increase in the respiratory rate
Which of the following will increase the rate of diffusion? -An increase in the viscosity of the solvent -An increase in the temperature -An increase in the molecular weight of the diffusing particles -An increase in the distance the molecules have to travel -All of the choices are correct.
An increase in the temperature
Which of the following is correctly matched with its description? -Glia - the conducting cell of the nervous system -Axon - carry action potentials toward the cell body -Neurons - supportive cells of the nervous system -Axons - conduct action potentials away from the cell body -Dendrite - rapidly dividing cell
Axons - conduct action potentials away from the cell body
Communication between cells is essential to coordinate the activity of the trillions of cells that make up the human body. Which of the following is/are directly involved in carrying out communication between cells? -Receptor proteins of the plasma membrane -Chemical signal molecules released by cells -Mitochondria -Lipid bilayer of the plasma membrane -Both "Receptor proteins of the plasma membrane" and "Chemical signal molecules released by cells" are correct.
Both "Receptor proteins of the plasma membrane" and "Chemical signal molecules released by cells" are correct.
Stimulation of the Golgi tendon organs result in which of the following changes in the reflex arc? -Stimulation of a stimulatory interneuron -Stimulation of an inhibitory neuron -Decreased action potentials in alpha motor neurons -Contraction of skeletal muscle fibers -Both "stimulation of an inhibitory neuron" and "decreased action potentials in alpha motor neurons" are correct.
Both "stimulation of an inhibitory neuron" and "decreased action potentials in alpha motor neurons" are correct.
Which of the following statements regarding the sliding filament model is false? -Actin and myosin do not shorten during contraction. -Both actin and myosin myofilaments shorten during contraction. -The sarcomere shortens. -The I band and H zones become narrower during contraction. -The A band remains constant in length.
Both actin and myosin myofilaments shorten during
Each voltage-gated Na+ channel has two voltage sensitive gates: an activation gate and an inactivation gate. Which of the following would occur during depolarization? -Activation gates are open; inactivation gates are closed. -Activation gates are closed; inactivation gates are open. -Both activation and inactivation gates are open. -Both activation and inactivation gates are closed. -None of the choices are correct.
Both activation and inactivation gates are open.
The processes of intramembranous and endochondral ossification are similar in several respects. Which of the following statements applies to both intramembranous ossification and endochondral ossification? -Chondrocytes participate in both processes. -In both processes, bone replaces cartilage. -Both processes require a precursor of connective tissue membranes. -Both processes form woven bone. -Both only form flat bones.
Both processes form woven bone.
The molecule used most frequently by cells as a fuel belongs to which of the following groups? -Prostaglandins -Carbohydrates -Steroids -Nucleic acids -Phospholipids
Carbohydrates
Which of the following systems carries necessary compounds like oxygen and nutrients throughout the body? -Nervous -Cardiovascular -Urinary -Lymphatic -Respiratory
Cardiovascular
Which of the following type of connective tissue is mismatched with its matrix? -Blood - fluid matrix -Cartilage - highly vascular matrix -Areolar - loosely packed matrix of protein fibers -Bone - mineralized matrix -Bone - highly vascular
Cartilage - highly vascular matrix
Which of the following is responsible for problem-solving skills? -Central nervous system -Peripheral nervous system -Somatic nervous system -Autonomic nervous system -None of the choices are correct.
Central nervous system
Which of the following would be classified as a lipid? -Catalase - an enzyme -Sucrose - a disaccharide -Alanine - an amino acid -Starch - a polysaccharide -Cholesterol - a steroid
Cholesterol - a steroid
Which of the following situations occurs in electrically excitable cells? -When Na+ ion channels open, K+ ion channels close. -The sodium-potassium pump moves sodium into the cell. -Depolarization causes voltage-gated sodium ion channels to open. -Sodium ion channels are opened by high extracellular calcium levels. -The opening and closing of ligand-gated channels cause depolarization.
Depolarization causes voltage-gated sodium ion channels to open.
Which of the following statements concerning epithelial cell surfaces is false? -Epithelium with folded surfaces tends to be very rigid. -Epithelium with folded surfaces can change shape. -Cilia propel materials along the surface of an epithelial cell. -Smooth surfaces reduce friction. -Epithelial cells with microvilli are involved in absorption.
Epithelium with folded surfaces tends to be very rigid.
Which of the following is true about skeletal muscle? -Sensory neurons stimulate muscles to contract. -There are very few blood vessels in skeletal muscle. -Every muscle fiber receives a branch of an axon from the nerve. -There are very few nerve fibers in a muscle. -All of the choices are true.
Every muscle fiber receives a branch of an axon from the nerve.
Which of the following statements about bone remodeling and repair is correct? -As a long bone increases in diameter, the size of the marrow cavity decreases. -Bone remodeling involves removal of old bone by osteoblasts. -Exposure of a bone to increased mechanical stress can lead to bone remodeling. -Bone remodeling does not involve the activity of the osteoclasts and the osteoblasts. -The rate of bone remodeling increases in the elderly.
Exposure of a bone to increased mechanical stress can lead to bone remodeling.
Which of the following anatomical features of bones is correctly matched with its function? -Body - attachment point for a tendon or ligament -Foramen - a hole for a blood vessel -Sinus - a tunnel in a bone -Foramen - a depression in a bone -Tubercle - lining of a joint
Foramen - a hole for a blood vessel
In the reversible reaction, CO2 + H2O ↔ H2CO3 ↔ H+ + HCO3- , a decrease in respiration rate will increase the concentration of CO2 in the blood. What will this do to the amount of H+ in the blood? -H+ will decrease. -H+ will increase. -H+ will be unchanged.
H+ will increase.
Which of the following characteristics is NOT consistent with simple squamous epithelial tissue? -Rest on a basement membrane -Acts as a permeability barrier -Little extracellular material -The cells are thin and flat (not thick) -Has good blood supply within it
Has good blood supply within it
Which of the following is associated with osteoclast reabsorption of bone? -Osteoblasts form collagen and proteoglycans. -The protein components of bone matrix are synthesized. -Blood calcium is decreased. -Calcium ions are actively transported from blood to bone matrix. -Hydrogen ions form an acid environment in bone matrix.
Hydrogen ions form an acid environment in bone matrix.
A young boy (10 years old) exhibited the following symptoms: advanced development of secondary sexual characteristics and rapid growth. Which of the following likely caused his condition? -Hypersecretion of growth hormone -Hypersecretion of estrogen -Hypersecretion of vitamin D -Hyposecretion of estrogen -Hypersecretion of testosterone
Hypersecretion of testosterone
Thirteen year-old Austin exhibits retarded growth, reduced metabolism, lack of normal reproductive gland development, inability to regulate water intake or water elimination from the body, and an uncontrolled appetite. Which part of Austin's brain is most likely involved? Reticular formation Primary sensory cortex Medulla oblongata Thalamus Hypothalamus
Hypothalamus
Which of the following brain areas serves as the major control center of the autonomic nervous system and endocrine system? Hypothalamus Midbrain Pons ThalamusIncorrect Brainstem
Hypothalamus
Which of the following would increase the rate of mediated transport? -Change the shape of the binding site on the carrier molecule -Increase the number of competitive molecules -Fill all binding sites on carrier molecules -Remove the binding site on the carrier molecule -Increase the number of available carrier molecules
Increase the number of available carrier molecules
Which of the following helps explain the increased tension seen in multiple wave summation? -Increased motor unit recruitment -Increased concentration of Ca2+ around the myofibrils -Exposure of more active sites on myosin myofilaments -The breakdown of elastic elements in the cell -Decreased stimulus frequency
Increased concentration of Ca2+ around the myofibrils
Which of the following bones forms part of the lateral wall of the nasal cavity? -Frontal -Sphenoid -Nasal -Vomer -Inferior nasal conchae
Inferior nasal conchae
Which type of cell phagocytizes foreign or injured cells and plays a major role in providing protection against infections? -Macrophage -Adipocyte -Stem cell -Osteoclast -Mast cell
Macrophage
Which of the following facial bones is correctly matched with its function? -Inferior nasal conchae - contain nasolacrimal canals -Temporal - is part of the orbit -Maxilla - possesses sockets for teeth -Vomer - forms the hard palate -Zygomatic - provides attachment point for temporalis muscle
Maxilla - possesses sockets for teeth
Frank has a microbial infection attacking his brain. Which cell type would you expect to proliferate and be most active during this time? -Astrocytes -Microglia -Oligodendrocytes -Ependymal cells -Schwann cells
Microglia
Solution A contains 5 grams of sugar per liter while solution B contains 2 grams of sugar per liter. The solutions are separated by a selectively permeable membrane. If the solvent in both solutions is water, predict in which direction most of the water molecules will move. -Most of the water will move by simple diffusion from solution A to solution B. -Most of the water will move by osmosis from solution B to solution A. -Most of the water will move by active transport from solution B to solution A. -Most of the water will move by filtration from solution A to solution B. -There will be no movement of water.
Most of the water will move by osmosis from solution B to solution A.
Which of the following actions is caused by contraction of skeletal muscle? -Contraction of the heart -Moving your feet in walking -Movement of food through the digestive tract -Emptying of the urinary bladder -Vasoconstriction
Moving your feet in walking
Which of the following is mismatched? I band - contains only actin M line - middle of the H zone Z disk - structure between adjacent sarcomeres Myosin myofilaments - thin myofilaments Actin myofilaments - thin myofilaments
Myosin myofilaments - thin myofilaments
Which branch of physiology would study the effects of sunbathing on the skin? -Cell physiology -Systemic physiology -Regional physiology -Organ physiology
Organ physiology
Which of the following is correctly matched? -Periosteum - lines the medullary cavity -Endosteum - lines central canal of the osteon -Osteoblast - breaks down bone tissue -Osteoclast - responsible for reabsorption -Osteocyte - functions in bone remodeling
Osteoclast - responsible for reabsorption
Which of the following statements regarding PTH (parathyroid hormone) is true? -PTH causes increased Na+ reabsorption in the kidneys. -PTH causes decreased vitamin D formation in the kidneys. -PTH causes increased loss of Ca2+ from the kidneys. -PTH causes increased reabsorption of Ca2+ in the kidneys. -PTH causes decreased uptake of Ca2+ from the small intestine.
PTH causes increased reabsorption of Ca2+ in the kidneys.
Damage to which of these nerves would be most life-threatening? -Median nerves -Phrenic nerves -Lumbar nerves -Sciatic nerves -Radial nerves
Phrenic nerves
Which two portions of the brain are involved in controlling respiration? -Pons, hypothalamus -Cerebrum, hypothalamus -Pons, medulla oblongata -Medulla oblongata, cerebral peduncles -Pons, thalamus
Pons, medulla oblongata
Which of the following is NOT a function of carbohydrates in the body? -Protection -Structural component of DNA -Energy -Structural component of RNA -Bulk in feces
Protection
Which function of proteins is NOT correctly matched with the example? -Protection - packing around organs and glands -Contraction - actin and myosin in muscles -Transport - hemoglobin -Regulation - enzymes and hormones -Structure - collagen and keratin
Protection - packing around organs and glands
Which of the following is NOT a function of cerebrospinal fluid? Provides oxygen to CNS tissue Provides nutrients to CNS tissue Provides a protective cushion around the CNS Protects the brain from rapid, jarring head movements
Provides oxygen to CNS tissue
Which of the following is CORRECTLY matched with its function? -Channel proteins - are part of an intercellular communication system -Nongated ion channels - are always closed -Peripheral proteins - penetrate the lipid bilayer from one surface to the other -Marker molecules - are primarily steroids -Receptor proteins - attach to ligand molecules
Receptor proteins - attach to ligand molecules
Which of the following statements concerning the epidermis is true? -The most numerous cells in the epidermis are the melanocytes. -The epidermis is very permeable to water-soluble molecules. -The epidermis is nourished by blood vessels located in the dermis. -The epidermis contains numerous blood vessels. -The dermis is superficial to the epidermis.
The epidermis is nourished by blood vessels located in the dermis.
Vitamin C is essential for normal collagen synthesis. If a child suffered from a vitamin C deficiency, which layer of the skin would be most affected? -Stratum corneum -Epidermis -Stratum basale -Stratum granulosum -Reticular layer of dermis
Reticular layer of dermis
Arrange these structures as they participate in excitation-contraction. T tubules, sarcolemma, Ca2+, sarcoplasmic reticulum Ca2+, T tubules, sarcolemma, sarcoplasmic reticulum Sarcolemma, T tubules, sarcoplasmic reticulum, Ca2+ Sarcoplasmic reticulum, Ca2+, T tubules, sarcolemma Sarcolemma, sarcoplasmic reticulum, Ca2+, T tubules
Sarcolemma, T tubules, sarcoplasmic reticulum, Ca2+
Which of the following events of endochondral ossification occurs last? -Secondary ossification centers appear in the epiphyses. -Cartilage is calcified in the cartilage model. -Blood vessels grow into the primary ossification center. -A cartilage model is formed by chondroblasts. -Osteoblasts produce trabeculae and lamellae on the surface of calcified cartilage.
Secondary ossification centers appear in the epiphyses
A twelve-year old girl has not yet experienced a bone growth spurt. Which particular chemicals must her body produce before this can occur? -Vitamin D -Growth hormone -Calcitonin -Sex hormones -Parathyroid hormone
Sex hormones
Which layer of the epidermis is found in only a few areas of the body? -Stratum lucidum -Stratum granulosum -Stratum corneum -Stratum spinosum -Stratum basale
Stratum lucidum
Which of the following is a carbohydrate? -Cholesterol -Animal fat -Triglyceride -Sucrose -Hemoglobin
Sucrose
Which of the following is an organic compound? -Hydrochloric acid (HCl) -Salt (NaCl) -Sucrose (C12H22O11) -Water (H2O) -None of the choices are correct.
Sucrose (C12H22O11)
Suppose both excitatory and inhibitory neurons synapse with a single postsynaptic neuron. What determines if an action potential is initiated in the postsynaptic neuron? -The kind of neuron involved -The size of the neuron involved -Whether the neuron is myelinated or non-myelinated -The number of EPSPs in relation to the number of IPSPs -This situation is not possible in humans.
The number of EPSPs in relation to the number of IPSPs
Which of the following statements concerning the subcutaneous layer is false? -The subcutaneous layer is composed of dense connective tissue with collagen and elastin fibers. -The subcutaneous layer is a site of lipid storage. -The subcutaneous layer can also be referred to as the hypodermis. -The main cell types of the subcutaneous layer are fibroblasts, adipocytes, and macrophages. -The subcutaneous layer attaches the skin to underlying bone and muscle.
The subcutaneous layer is composed of dense connective tissue with collagen and elastin fibers.
Which of the following statements concerning the structure of spinal nerves is true? -The ventral root contains motor or efferent fibers. -The ventral root has a prominent root ganglion. -Rootlets from the surface of the spinal cord form the dorsal and ventral rami. -Each spinal nerve is formed by the union of a cranial nerve and a spinal nerve. -Spinal nerves do not have specific cutaneous distributions.
The ventral root contains motor or efferent fibers.
Which of the following statements concerning the vertebrae is true? -The first cervical vertebra is called the axis. -The spinal cord protects the vertebral column. -Thoracic vertebrae have long, thin spinous processes. -The sacral vertebrae are superior to the lumbar vertebrae. -Lumbar vertebrae are generally smaller than thoracic vertebrae.
Thoracic vertebrae have long, thin spinous processes.
What is the permeability barrier that joins the plasma membranes of adjacent cells to form a tight seal? -Hemidesmosomes -Tight junction -Gap junction -Desmosomes -Adhesion belt
Tight junction
Which of the following cranial nerves is exclusively sensory? Vestibulocochlear (VIII) Hypoglossal (XII) Trochlear (IV) Facial (VI) Trigeminal (V)
Vestibulocochlear (VIII)
Which of the following statements concerning vitamin D is false? -Vitamin D is important for calcium homeostasis. -Vitamin D causes the kidney to excrete calcium. -Vitamin D is necessary for the formation of bones and teeth. -Vitamin D begins its synthesis in the skin when the skin is exposed to ultraviolet light. -Vitamin D is necessary for the uptake of calcium from the intestine.
Vitamin D causes the kidney to excrete calcium.
Which of the following bones form the nasal septum? -Vomer and ethmoid -Nasal and vomer -Inferior nasal conchae and lacrimal bones -Maxilla and vomer -Ethmoid and sphenoid
Vomer and ethmoid
Which of the following statements is false? -Water transports nutrients in the body. -Water allows the body to resist sudden temperature changes. -Water evaporation cools the body. -Water evaporation heats the body. -Water serves as an effective lubricant in our bodies.
Water evaporation heats the body.
Which of the following statements regarding calcium homeostasis is true? -Calcitonin elevates blood calcium levels. -Parathyroid hormone increases calcium loss from the kidney. -Increased osteoblast activity increases blood calcium levels. -When blood calcium levels are too low, osteoclast activity increases. -Parathyroid hormone inhibits osteoclast activity.
When blood calcium levels are too low, osteoclast activity increases.
An isotonic contraction is described as -action potential frequency is high enough that no relaxation of muscle fibers occurs. -a muscle produces constant tension during contraction. -a muscle produces an increasing tension during contraction. -a muscle produces increasing tension as it shortens. -a muscle produces tension, but the length of the muscle is increasing.
a muscle produces constant tension during contraction.
An organ is -a small structure within a cell. -a structure composed of several tissue types. -the basic structural unit of all living organisms. -a group of molecules with a common set of functions. -a group of cells with similar structure and function.
a structure composed of several tissue types.
An electrolyte is -a combination of atoms held together by chemical bonds. -the alteration in the three-dimensional structure of a protein. -a positively charged ion. -a negatively charged ion. -a substance that conducts electricity when placed in solution.
a substance that conducts electricity when placed in solution.
When a neurotransmitter binds to its receptor and increases the permeability of the postsynaptic membrane to Na+, -the membrane will be hyperpolarized. -more Cl− will also diffuse into the cell. -an excitatory postsynaptic potential (EPSP) will result. -the membrane will become impermeable to K+. -Na+ diffuses out of the cell.
an excitatory postsynaptic potential (EPSP) will result.
All of the synthesis reactions in the body are called _________. -dissociation -hydrolysis -oxidation-reduction -catabolism -anabolism
anabolism
The thumb and the big toe are similar in that they? -both contain carpal bones. -each have three metatarsals. -both are composed of sesamoid bones. -both have two rather than three phalanges. -both have three rather than two phalanges.
both have two rather than three phalanges.
The three types of protein fibers found in connective tissue are -proteoglycan, elastin, and reticular fibers. -chondronectic, osteonectin, and fibronectin. -proteoglycan, elastin, and hyaluronic acid. -hyaluronic acid, collagen, and reticular fibers. -collagen, elastin, and reticular fibers.
collagen, elastin, and reticular fibers.
In the spinal cord, white matter is organized into -horns and the gray matter into columns. -horns and the gray matter into roots. -columns and the gray matter into horns. -columns and the gray matter into tracts.
columns and the gray matter into horns.
The absolute refractory period assures -prolonged depolarization during the action potential. -completion of repolarization before another action potential. -that no after-potential occurs. -reversal of the direction of propagation of the action potential. -that the stimulus is strong enough to elicit a response.
completion of repolarization before another action potential.
Osteoblasts involved in bone growth in length come primarily from -periosteum. -connective tissue surrounding blood vessels of the endosteum. -chondrocytes.Incorrect -endothelium of blood vessels. -osteocytes.
connective tissue surrounding blood vessels of the endosteum.
A general characteristic of connective tissue is that it -consists of cells with much extracellular material (matrix) between them. -has no blood supply to the tissue. -is commonly found lining body cavities. -covers the outside of organs. -contracts.
consists of cells with much extracellular material (matrix) between them.
The cerebral medulla has the same function as the medulla oblongata. is the gray matter on the cerebrum's surface. consists of many nerve tracts of white matter beneath the cerebral cortex. is another name for the basal nuclei. is the outer layer of the cerebrum.
consists of many nerve tracts of white matter beneath the cerebral cortex.
The stratum basale -is easily shed when you rub your hands together. -contains cells that undergo mitosis to form new epidermal cells. -contains cells that undergo meiosis to form new epidermal cells. -contains many blood vessels that nourish the epidermis. -has a mixture of living and dead cells—mostly dead.
contains cells that undergo mitosis to form new epidermal cells.
Cartilage -contains chondrocytes located in lacunae. -is well vascularized. -is surrounded by a membrane called the periosteum. -is composed of osteons. -does not need nutrients and oxygen, so it has no blood vessels.
contains chondrocytes located in lacunae.
Spongy bone tissue -contains concentric lamellae. -is the primary component of compact bone. -has many spaces and lacks osteocytes. -contains interconnecting plates called trabeculae. -is very dense.
contains interconnecting plates called trabeculae.
Lack of acetylcholinesterase in the synaptic cleft would result in -a decrease in acetylcholine production by the motor neuron. -continuous stimulation of the postsynaptic membrane. -rapid degradation of acetylcholine. -relaxation of the muscle. -continuous stimulation of the presynaptic membrane.
continuous stimulation of the postsynaptic membrane.
If Na+ cannot enter a muscle fiber in response to a stimulus, -contraction cannot occur. -relaxation cannot occur. -Na+ will be released from the sarcoplasmic reticulum instead. -the active sites are left exposed. -the action potential travels into the muscle anyway.
contraction cannot occur.
In ionic bonding, -a "sea of electrons" forms. -the charge of the ion does not play a role in the bond. -two hydrogen atoms share one pair of electrons. -only non-polar molecules are involved. -electrons are transferred from one atom to another.
electrons are transferred from one atom to another.
A particular membrane transport process exhibits saturation, uses carrier molecules, but does NOT require ATP. The process is probably _________. -pinocytosis -facilitated diffusion -phagocytosis -osmosis -active transport
facilitated diffusion
A local potential -does not occur until threshold. -transmits information from one cell to another. -might be a depolarization event but cannot be a hyperpolarization event. -increases or decreases in direct proportion to the stimulus strength. -does not alter resting membrane potential.
increases or decreases in direct proportion to the stimulus strength.
The secretions of endocrine glands are released directly -into the lumen of a tube.Incorrect -onto the skin surface. -into the bloodstream.Correct -into a gland duct. -into the nervous tissue.
into the bloodstream.
Hyaluronic acid gives a very slippery quality to fluids that contain it. Hyaluronic acid -is a protein. -functions as an insulator. -promotes oxygen transport in the plasma. -is a good lubricant for joint cavities. -resists stretching.
is a good lubricant for joint cavities.
Complete tetanus -is the time during which the tissue cannot respond again. -results in complete and incomplete tetanus. -is the condition in which the muscle fiber only partially relaxes between contractions. -is the condition in which stimuli occur so rapidly that there are no intervening relaxations. -is the constant tension produced by muscles for long periods of time.
is the condition in which stimuli occur so rapidly that there are no intervening relaxations.
A small lesion in the brainstem which resulted in a rapid heart rate, intense vasoconstriction, and elevated blood pressure would probably be located in the __________. -medulla oblongata -pons -cerebellum -hypothalamus -cerebrum
medulla oblongata
When the myosin head flexes into a bend, pulling the actin filament along with it, this is called the -action reaction. -power stroke. -recovery stroke. -muscle tone. -action potential.
power stroke.
The adaptive significance of the crossed extensor reflex when a person steps on a tack is to -remove the foot from the tack. -increase the rate at which withdrawal of the limb occurs. -slow the rate of removal of the foot from the tack. -reduce the pain sensations. -prevent the person from falling down.
prevent the person from falling down.
The sequence of events that produces growth at the epiphyseal plate is -hypertrophy, calcification, proliferation, cell death, ossification, and remodeling. -calcification, hypertrophy, proliferation, ossification, cell death, and remodeling. -proliferation, hypertrophy, calcification, cell death, ossification, and remodeling. -hypertrophy, proliferation, calcification, ossification, and remodeling. -proliferation, hypertrophy, cell death, calcification, ossification, and remodeling.
proliferation, hypertrophy, calcification, cell death, ossification, and remodeling.
A myofilament is the -plasma membrane of a muscle fiber. -cytoplasm of a muscle fiber. -structural and functional unit of the skeletal muscle fiber. -contractile thread that extends the length of the muscle fiber. -protein strand composed of actin or myosin.
protein strand composed of actin or myosin.
A term that means "toward the attached end of a limb" is _________. -medial -lateral -superficial -distal -proximal
proximal
The shoulder is _________blank to the elbow. -lateral -dorsal -distal -ventral -proximal
proximal
The type of membrane that protects internal organs from friction is a _________membrane. -synovial -partial -serous -plasma -mucous
serous
Hypertrophy of skeletal muscles from weight lifting is caused by an increase in the -number of muscle fibers. -size of muscle fibers. -number of striations. -number of nuclei within the muscle fibers. -number of muscle cells.
size of muscle fibers.
When two action potentials arrive simultaneously at two different presynaptic terminals that synapse with the same postsynaptic neuron, -the direction of the action potential is reversed. -temporal summation occurs. -spatial summation occurs. -hyperpolarization occurs. -threshold is never reached.
spatial summation occurs.
The layer of epidermis that undergoes mitosis and forms new epidermal cells is the __________. -stratum corneum -stratum lucidum -stratum granulosum -stratum dermum -stratum basale
stratum basale
In order for muscle relaxation to occur, -Ca2+ must be transported to troponin. -power strokes slow down. -the active sites on actin must be blocked. -Na+ must be actively transported to troponin. -the active sites on myosin must be uncovered.
the active sites on actin must be blocked.
The longitudinal growth of long bones ceases when -the bone marrow forms. -the periosteum is completed. -the epiphysis becomes separated from the diaphysis. -chondroblasts take over mitosis of osteoblasts. -the epiphyseal plate is completely replaced with bone tissue.
the epiphyseal plate is completely replaced with bone tissue.
The plasma membrane of a neuron is more permeable to K+ because -of its positive electrical charge. -there are more leak ion channels for K+ than Na+. -protein molecules cannot exit through the plasma membrane. -Ca2+ block Na+ and Cl− channels. -there are more leak ion channels for Na+ than K+.
there are more leak ion channels for K+ than Na+.
The plasma membrane of an excitable cell is more permeable to K+ because -of its positive electrical charge. -there are more leak ion channels for K+ than Na+. -protein molecules cannot exit through the plasma membrane. -calcium ions block Na+ and Cl- channels. -there are more gated channels for K+.
there are more leak ion channels for K+ than Na+.
In some cells, an afterpotential occurs because -the Na+ continue to enter the cell after depolarization is finished. -there is prolonged, elevated permeability to K+ during repolarization. -the sodium-potassium pump is actively exchanging ions across the membrane. -the extracellular Na+ concentration is reduced. -the permeability to Na+ continues longer than necessary.
there is prolonged, elevated permeability to K+ during repolarization.