BIO 2870 CHP 7

sensory neuron; myelin-covered internode;

A neuron that sends messages to the CNS, and which is composed of one or more dendrites and a single axon, is functionally classified as a(n) ___. The nodes are found in between the ___.

maintaining the normal concentrations of calcium and phosphate ions in body fluids.

A primary function of the skeletal system is A primary function of the skeletal system is maintaining the normal concentrations of calcium and phosphate ions in body fluids. facilitating transmission of nerve impulses. contracting muscles. absorbing the shock of unexpected rapid body movements. cushioning abdominal organs such as the kidneys.

hyperpolarization;

A stimulus that opens gated potassium ion channels, moving the membrane voltage value below the resting potential value, results in ___.

sodium ions.

As a skeletal muscle contraction is initiated, acetylcholine binding alters the motor end plate membrane's permeability to As a skeletal muscle contraction is initiated, acetylcholine binding alters the motor end plate membrane's permeability to: acetylcholinesterase. chloride ions. sodium ions. calcium ions. potassium ions.

isometric contraction

As you unsuccessfully attempt to lift the 300-pound weights off the ground, you are demonstrating ________. As you unsuccessfully attempt to lift the 300-pound weights off the ground, you are demonstrating ________. isotonic contraction hypertonic contraction hypotonic contraction isometric contraction

Glucose and fatty acids are catabolized.

During moderate activity, which of the following is true regarding muscle metabolism? During moderate activity, which of the following is true regarding muscle metabolism? Mitochondrial activity provides about one-third of the ATP consumed. Mitochondria are not involved. Glucose and fatty acids are catabolized. The ATP produced is used to build energy reserves of ATP and glycogen. Most ATP is produced through glycolysis, with lactate and hydrogen ions as byproducts.

is an anaerobic process.

Glycolysis: Glycolysis acts as the only source of ATP in muscle tissue. occurs in the nucleus. is the breakdown of pyruvate to glucose. is an anaerobic process. is only active during rest.

3,1,2,4

Identify the correct sequence of steps in the generation of an action potential. 1. Activation of sodium channels and rapid depolarization 2. Inactivation of sodium channels and activation of potassium channels 3. Depolarization to threshold 4. Closing of potassium channels

convergent neuronal pools.

Multiple areas of the brain can regulate breathing at the same time by stimulating the diaphragm for contraction. This activity is best explained by the all-or-none principle. divergent neuronal pools. saltatory conduction. linear neuronal pools. convergent neuronal pools.

Chondrocytes are cartilage cells found within the cartilage matrix in small pockets known as lacunae. NO Fibroblasts yes

Recall that a synovial membrane lines the cavity of a freely movable joint (as you in saw Chapter 4: The Tissue Level of Organization). The synovial fluid it secretes lubricates the joint and permits smooth movement. What kind of cells secrete the synovial fluid? Recall that a synovial membrane lines the cavity of a freely movable joint (as you in saw Chapter 4: The Tissue Level of Organization). The synovial fluid it secretes lubricates the joint and permits smooth movement. What kind of cells secrete the synovial fluid? mucosae chondrocytes fibroblasts plasma cells

A band.

The region of a sarcomere containing myosin, going from one end of the myosin molecules to the other end of the myosin molecules, is the The region of a sarcomere containing myosin, going from one end of the myosin molecules to the other end of the myosin molecules, is the M line. I band. Z line. A band. H band.

ATP.

The stiffness that occurs at death, when actin and myosin molecules stay linked to each other in a contracted state, is due to a lack of The stiffness that occurs at death, when actin and myosin molecules stay linked to each other in a contracted state, is due to a lack of tRNA. RNA. cAMP. ATP. DNA.

acetylcholine is released.

Upon the nerve impulse arriving at the axon terminal, Upon the nerve impulse arriving at the axon terminal, actin heads will bind to myosin. muscle relaxation occurs. acetylcholine is released. active sites on actin are exposed. active sites on myosin are exposed.

H-band, sarcomere, myofibril, muscle fiber, fascicle, muscle

Which of the following is ranked from smallest to largest? Which of the following is ranked from smallest to largest? Muscle, fascicle, myofibril, muscle fiber, H-band, sarcomere Muscle, fascicle, muscle fiber, myofibril, sarcomere, H-band H-band, sarcomere, myofibril, muscle fiber, fascicle, muscle Sarcomere, H-band, muscle fiber, myofibril, fascicle, muscle

4132

Which of the following is the correct order of events that occur at a cholinergic synapse? 1. Extracellular calcium enters the axon terminal, triggering the exocytosis of acetylcholine. 2. Acetylcholine is removed by acetylcholinesterase. 3. Acetylcholine binds to receptors and depolarizes the postsynaptic membrane. 4. Axon terminal depolarizes.

Skeletal muscles contain blood vessels.

Which statement regarding skeletal muscle is true? Which statement regarding skeletal muscle is true? Skeletal muscles do not maintain body temperature. Skeletal muscles are directly, but not indirectly, attached to bones. Skeletal muscles do not contain connective tissue. Skeletal muscles do not contain nervous tissue. Skeletal muscles contain blood vessels.

Multiple twitches add up to an increase in muscle fiber tension, which increases the strength of the muscle.

Why do individual muscle twitches have to be added together, as in summation or tetanus? Why do individual muscle twitches have to be added together, as in summation or tetanus? Not enough ATP is generated by one muscle twitch. Only added twitches produce any muscle contraction: A fiber undergoing a muscle twitch does not contract at all. Not enough acetylcholine will be produced for contraction without multiple twitches. There has to be a critical mass of muscle twitches for calcium to be released into the muscle cell. Multiple twitches add up to an increase in muscle fiber tension, which increases the strength of the muscle.

Interneurons; 5,7,1,4,3,6,2

___ are found only in the central nervous system. 1. Sodium enters the cell. 2. Cell is repolarized. 3. Voltage-gated sodium channels close as voltage-gated potassium channels open. 4. Cell is depolarized. 5. A stimulus arrives. 6. Potassium leaves the cell. 7. Voltage-gated sodium channels open

oligodendrocyte; Saltatory conduction; Sensory neurons; sensory and motor neurons; Motor neurons;

___ myelinates short segments of several axons, and many of them are needed to coat an entire axon with myelin. ___ is faster than conduction on an unmyelinated axon. ___ receive impulses and carry them from the sense organs to the spinal cord or brain. Interneurons connect ___ and ___ and interpret the impulse. ___ carry impulses from the brain and spinal cord to muscles or glands.

Acetylcholinesterase or AChE

___ quickly breaks down the ACh on the motor end plate and in the synaptic cleft, thus inactivating the ACh receptors.