Physiology of Exercise Science
Terms in this set (86)
Which type of contraction primarily occurs in the quads as a person descends a flight of stairs?
The speed of muscle fiber contraction is determined primarily by:
speed of myosin ATPase
What is the correct order of skeletal muscle hierarchical organization, from largest structure to smallest structure?
entire muscle, muscle fascicles, muscle fiber, myofibril
Epimysium relates to entire muscle as endomysium relates to:
Thick filaments are primarily made of which protein?
Why is it necessary to have an AP in the muscle for contraction?
The SR will only release CA2+ if it has been electrically stimulated
T/F: The sarcoplasm is specially designed to conduct AP received from alpha motor neurons?
The process of muscle contraction involved which ion?
Which protein shields the myosin-binding site, preventing contraction from happening at rest?
T/F: If you change your training mode from aerobic endurance to resistance training, you can dramatically influence the ratio of type I to type II fibers in your muscles.
T/F: Thick Filaments are anchored to the Z disk, which think filaments are anchored to the M-line
Which protein is sensitive to CA2+ and thereby helps initiate contraction?
T/F: Genetic factors appear to be most influential in determining the percentage of type I vs. type II fibers
CA2+ ions (essential for contraction) are stored in the:
What is true about the leg muscle fibers from an olympic sprinter vs. an olympic marathon runner?
The amount of force generated by similar sized muscle fibers is similar
T/F: If I need to lift a heavy box of books, I will be most successful if I try to lift it quickly and use momentum to help me.
Glycogen is stored in which region of a muscle fiber?
Muscle found in the walls of the bladder is an example of:
The process of plasmalemma depolarization involves which ion?
Type I muscle fibers have a _____________ oxidative capacity.
T/F: According to the length-tension relationship, a muscle will be functionally weaker if it is too stretched or too short.
Muscle contraction that results in a change in joint angle is called:
T/F: For a heat lifting task, type IIx are recruited first because they are most appropriate for the job.
T/F: Concentric contractions make up more than 95% of all muscle contractions that we perform.
Why does a sarcomere that is too short or too stretched produce less force?
not as many cross-bridges can form
As intensity increases, in which order are fibers recruited?
type I, type IIa, type IIx
Which contractile results of rate coding will produce the most force?
According the the size principle, which motor unit will be recruited first for a task?
The motor unit with the smallest motor neuron
Thin filaments are often named for which protein?
ATP is required for:
both muscle contraction and relaxation
T/F: Individual muscle fasiculi are divided into sarcomeres.
T/F: Both type II fibers and type II motor units tend to be larger compared to type I fibers and motor units.
What is the correct order of events in a contraction?
T-tuble AP, CA2+ released, cross-bridging, CA2+ gathered in
If a type I fiber and a type II fiber of the same size are stimulated side by side, what will happen?
they will generate the same amount of force
The breakdown of a triglyceride into its components is called:
T/F: Cells can store large quantities of ATP in anticipation of prolonged intense exercise.
When ADP accumulates, what is the effect on the rate of metabolic chemical reactions?
speeds them up
In which part of the cell does glycolysis occur?
How do products of a metabolic pathway typically help control the rate of the chemical reactions?
negatively feed back on the rate-limiting enzyme
The ATP-PCR system would be the primary ATP source for which event?
50 m sprint
What is responsible for lowering the activation energy of a chemical reaction?
T/F: Not all muscles exhibit the same degree of oxidative capacity.
Taking into account both oxygen requirements and ATP yield, which substrate is more efficient, fat or glucose?
The anaerobic glycolytic system would be the primary source of ATP for what running event?
800 m (1/2 mile) run
In the presence of oxygen, the final product of glycolysis is:
Which energy substrate contains the most energy per gram?
ATP + water + ATPase =
ADP + Pi + energy
The ATP -PCr metabolic system can be best described as:
The process of adding a phosphate ground to ADP is called?
What factor causes fatigue after 1-2 minute of high-intensity exercise?
lactic and accumulation
A response associated with increasing oxidative metabolism in an exercising muscle is:
high heart rate
T/F: Adenosine consists of adenine + ribose + 3 phosphate groups.
During the 400m sprint (50-60 seconds long), which 2 metabolic pathways will be primarily involved?
ATP - PCr, glycolysis
T/F: Enzymes trigger the onset of chemical reactions.
An example of an energy substate is _______
Many marathon runners "hit the wall" around mile 20. What does this tell you about glycogen?
Glycogen stores are mostly depleted by mile 20
Which substrate stores in the body can provide the most overall kilocalories?
ATP production from fat is _________ ATP production from glucose.
Protein can serve as an energy substrate if:
it is first converted to glucose
T/F: Glucose is the primary ATP substrate for the muscles and brain.
For aerobic metabolism, free fatty acids must be converted to acetyl-coA via:
T/F: FFA can only be used to produce ATP via aerobic metabolic pathways.
An athlete with a high percentage of type II fibers would exhibit what charactersistic?
fewer mitochondria, and lower oxidative enzymes
In the absence of oxygen, the final product of glycolysis is:
T/F: Anaerobic glycolysis can produce ATP in the absence of both oxygen and glucose.
Higher levels of succinate dehydrogenase in a muscle would indicate:
higher oxidative capacity
T/F: Human energy substrates are made of carbon, oxygen, hydrogen, and nitrogen.
In which part of the cell does oxidative phosphorylation occur?
T/F: Metabolic pathways such as those that cover energy substrates to ATP are controlled in part by negative feedback systems.
Under resting conditions, the ATP-Pcr system plays which role?
replenishing cellular ATP reserves
T/F: The amount of energy used by a chemical reaction can be calculated based on the amount of heat that is released.
Metabolic enzyme activity can increased by increasing the:
T/F: ATP and PCr can both be used for fueling cellular work for brief but intense exercise bouts.
Carbohydrate serves as field for ATP production during:
during short-duration, high-intensity exercise
A set of factors that determines the rate of ATP production:
substrate availability, enzyme activity
T/F: The primary motor cortex is responsible for the control of fine and discrete muscle movements.
Nocioreceptors are sensory receptors that respond to:
Two major neurotransmitters involved in regulating our physiological responses to exercise are ___________ and __________.
acetylcholine and norepinephrine
The brainstem is composed of:
the midbrain, the pons, and the medulla oblongata
Motor impulses for complex movement patterns (throwing a baseball or writing) typically originate at the level of the:
The two main components of the nervous system are:
the CNS and the PNS
A function of the frontal lobe of the brain is:
general intellect and motor control
What area within the CNS appears to be particularly important in coordinating body movements?
What is the proper sequence of events during sensory-motor integration?
sensory reception, sensory transmission, CNS processing and response selection, motor implies transmission, motor response
The velocity of nerve impulse transmission in large myelinated fibers can approach
The primary mechanism responsible for maintaining the resting membrane potential of a neuron is:
active pumping of NA + K ions across the neurological membrane by the NA-K pump.