The SI system of quantifying units is used because:
All of the following: It ensures standardization, it makes comparisons of published data easier, and it has been endorsed by numerous journals.
The SI unit used for work is:
If you push a 10 N weight up a vertical distance of 5 meters, the work performed would be:
The SI unit used for power is:
How much power would it take to complete the task described in notecard #3 if done in 5 seconds?
Energy expenditure and the energy content of food are usually expressed as:
The estimation of energy expenditure by measuring heat production is called:
It is not possible to calculate the work performed on a treadmill while:
The treadmill is horizontal.
True or False: An uneconomical runner would have a lower VO2 than an economical runner at the same speed.
Males and females have similar running economy at:
The energy requirement to walk on a treadmill is __________ the energy requirement to run at the same speed.
The most common technique used to measure oxygen consumption is:
Open Circuit Spirometry
A VO2 of 35 (ml)/(kg)(min) is equivalent to:
Net efficiency is defined as the ratio of:
Work output to energy expenditure above rest
The efficiency of exercise is influenced by:
All of the following: Exercise work rate, speed of movement, and fiber composition of muscles performing the exercise.
A difference in efficiency between muscles fibers is due to:
Different requirements in ATP per unit of work
The relationship between work rate and energy expenditure is:
The two major systems involved in the control of homeostatic bodily functions are:
Endocrine and nervous systems
The concentration of a hormone in the blood depends on:
All of the following: The rate of secretion of the hormone and changes in plasma volume.
The concentration of a hormone in the blood does NOT depend on:
The chemical structure of the hormone
True or False: The magnitude of the effect of a hormone on tissues is mostly determined by the free plasma hormone concentration.
If a hormone-receptor interaction activates a calcium ion channel and calcium enters the cell, it will often bind to:
In the activation of second messengers, what occurs after the hormone binds to the receptor?
G protein activates protein kinase C
Following the activation of adenylate cyclase, what molecule is formed from ATP?
Hormones released from the posterior pituitary gland include:
Catecholamines are secreted from:
The Adrenal Medulla
Aldosterone is secreted from:
The Adrenal Cortex
The binding of catecholamines to beta-2 receptors results in:
High blood levels of glucocorticoids can result in:
During exercise, the activation of phosphorylase:
All of the following: Is caused by epinephrine, is stimulated by intracellular calcium, and results in glycogenolysis.
Chronic exercise training _________ estrogen levels in females.
The maintenance of plasma glucose during exercise can be accomplished by:
All of the following: Liver glycogenolysis, mobilization of FFA, and liver gluconeogenesis.
Examples of the fast-acting hormones responsible for the maintenance of plasma glucose are:
Epinephrine and Norepinephrine
Given the decrease in blood insulin concentration during exercise, glucose uptake into muscle:
Increases up to 20 times
What factor serves to decrease FFA mobilization during intense exercise?
High levels of lactate
An excess of growth hormone in adults can cause:
The nervous system can be divided into:
All of the following: Central and peripheral, autonomic and somatic, and sensory and motor.
The axon carries the action potential:
Away from the nerve cell body
The discontinuous sheath that covers the outside of most axons is:
The resting membrane potential of a neuron is generally:
-40 to -75 mv
The resting membrane potential is maintained by:
The first step of the generation of an action potential is:
The entry of sodium into the cell
Neurotransmitters that cause depolarization of membranes are called:
The summing of several EPSP's from several presynaptic neurons at the same time is called:
All of the following: Muscle spindles, Golgi tendon organs, and joint receptors.
The withdrawal reflex results in:
Contraction of flexor muscles on the side stimulated
Slow, controlled movements are generated by the:
Evidence exists to suggest that the control of movement in response to feedback from proprioceptors is carried out by the:
The first step in performing a voluntary movement is thought to occur in the:
Subcortical and cortical areas
Neurons in the _________ division of the autonomic nervous system arise from the thoracic and lumbar regions of the spinal cord.
The neurotransmitter is released at the effector organ by the sympathetic nervous system is primarily:
Repolarization occurs due to:
All of the following: Increased permeability to potassium and decreased permeability to sodium.
Synaptic transmission occurs when:
Sufficient amounts of neurotransmitters are released
Regular exercise results in improved health through the production of:
Brain Growth Factors
The motor cortex controls motor activity with the aid of input from the:
A muscle responsible for fine movement would have a _________ innervation ration compared to a muscle involved in forceful movements.
The _____ functions as a length detector in muscle.
A slow stretch on a muscle would result in muscle relaxation via the:
Golgi tendon organ
The striated appearance of skeletal muscle is due to:
Arrangement of actin and myosin
Sarcomeres are divided from each separated other by:
Muscle fibers contract by the shortening of:
Z to Z line distance
What occurs during muscle contractions:
H zone narrows
The energy for muscular contraction comes from:
The breakdown of ATP by myosin ATPase
Muscle fibers with a relatively small low number of mitochondria are:
The red pigment of type I fibers is due to:
The predominant muscle fiber of non-athletes is:
What muscle fiber type composition would you expect to see in an elite track sprinter?
25-30% type I, 70-75% type II
Endurance training results may result in conversion of muscle fibers from:
Type IIx to Type IIa
A contraction where a muscle exerts tension but does not shorten in length is an:
The mount of force generated by a muscle fiber depends primarily on:
The number of actin/myosin cross bridges in contact
The velocity of muscle contraction is greatest when:
The load on the muscle is low
The amount of force generated by a group of muscles depends on:
All of the following: The type and number of motor units recruited, the initial length of the muscle, and the nature and frequency of the neural stimulation.
During exercise, muscular contractions are stimulated by:
Summation of successive twitches
The increase in muscle mass as a result of resistance training is due primarily to:
The loss of muscle mass in aging humans is often due to:
Atrophy due to disuse
From age 25 to 50 years, the muscle mass lost is around:
The muscle spindle acts directly on the:
True or False: Resistance training in the elderly can prevent further muscle loss, but cannot improve strength or endurance.
When comparing contractile properties of muscle fibers, which characteristics is/are important?
All of the following: Maximal force production, speed of contraction, and muscle fiber efficiency.
The fastest muscle fiber in humans is:
Type IIx fibers have:
Limited capacity for aerobic metabolism
In determining muscle fiber type, fibers with the lowest myosin ATPase activity are:
In the resting state, the myosin cross-bridges:
Remain connected to actin in a week binding state
The contraction cycle can continue as long as there is:
ADP present both a and b