PE 461 Midterm Fall 2022

Phosphocreatine breakdown is regulated by

Creatine kinase

Which of these is NOT part of an ATP molecule

An enzyme

5 carbon sugar

Adenine containing nitrogen

3 phosphate groups

An enzyme

Intracellular stores of ATP and PCr are sufficient to support maximum muscular effort for approximately

3-15 seconds

The two non-oxidative metabolic pathways are the

Phosphagen system and glycolysis

In order to lose 5 lbs of fat, how many more kcal must a person burn through exercise than they eat

17500

Which of these is NOT true?

Athletes should get 30-35% of their calories from protein

Gluconeogenesis is the production of glucose from amino acids

The American Heart Association recommends that people get 30% (or less) of their calories from fat

25 g of carbohydrate provides 100 kcal

Athletes should get 30-35% of their calories from protein

Which of these nutrients does NOT provide energy for our body

Vitamins

Fat

Protein

Carbohydrate

Vitamins

Which of the following statements is true regarding the relative roles of fat, carbohydrate, and protein as energy sources for cellular metabolism

Fat cannot provide all of the energy required for high-intensity muscular activity because the rate of energy release from fat is too low

Protein is the predominant fuel source during exercise

Much more energy is stored in the body in the form of carbohydrate the in the form of fat

Single glycogen reserves in the body are so large, only limited amounts of carbohydrate are needed in the daily diet

Fat cannot provide all of the energy required for high-intensity muscular activity because the rate of energy release from fat is too low

Which of these statements is NOT true?

As the exercise intensity increases, the body relies more on fats and less on carbohydrate for making ATP

A trained person uses more fat and less carbohydrate for a given submaximal exercise intensity

Intramuscular fat stores increase a little due to an exercise training program

At rest, about 47.5% of energy comes from fat, 47.5% from carbohydrate and 5% for protein (typically)

As the exercise intensity increases, the body relies more on fats and less on carbohydrate for making ATP

How much carbohydrate per day should a recreational athlete, who exercises 3-4 days per week at a moderate intensity for 45 minutes, eat?

3-6 grams/kg of body mass

In the human body, about what percent of energy released from the hydrolysis of ATP is used to produce muscle movement and other cellular processes?

30%

What is the main fuel used to make ATP during exercise

Carbohydrate

Which statement below is TRUE?

Protein can become carbohydrate

Fat can become protein

Carbohydrate can become protein

Fat can become carbohydrate

Protein can become carbohydrate

In order for glucose to be stored in the muscles or liver as a stored form of carbohydrate, it must be converted to which substance?

Glucose-1-phosphage

How is fat stored in the body?

As triglycerides

Which one of these statements is true?

Protein is primarily important for structural function in the human body

Carbohydrate is stored in large quantities in the human body

Eating a high protein/low carbohydrate diet is essential for appropriate adaptations to exercise

A high fat diet will enhance sports performance

Protein is primarily important for structural function in the human body

An energy system that uses all of its fuel from storage within the cytosol, does not use oxygen, and relies only a single enzyme describes which energy system?

Phosphagen system

Which one of these statements is NOT true?

Muscle glycogen can be used to maintain normal blood glucose levels

Excess carbohydrate intake will result in fat storage in the body

Fat is less readily converted to ATP than is carbohydrate

Liver glycogen can be used to maintain normal blood glucose levels

Muscle glycogen can be used to maintain normal blood glucose levels

The most important carbohydrate for ATP production in humans is

Glucose

The synthesis of molecules is called

Anabolism

The initial energy required to start a chemical reaction or chain of reactions

Activation energy

The addition of a phosphate group to a molecule

Phosphorylation

An enzyme found early in a metabolic pathway that determines the rate of the pathway

Rate limiting enzyme

The process of converting protein (or carbohydrate) into fatty acids

Lipogenesis

Term given to the study of processes that yield or consume energy in living organisms

Bioenergetics

Nerves that carry impulses towards the central nervous system.

Sensory nerves

An increase in electric potential across a cell membrane.

Hyperpolarization

A primary neurotransmitter that transmits impulses across the synaptic cleft, particularly in motor units between the nerve and the muscle cell.

Acetylcholine

A catecholamine released from the adrenal medulla that helps prepare the body for a fight-or-flight response. It's also a neurotransmitter secreted from most preganglionic nerves of the sympathetic nervous system.

Norepinephrine

The site at which a motor neuron communicates with a muscle fiber.

Neuromuscular junction

The cumulative effects of all the individual changes in a neurons membrane potential. Can also apply when multiple electrical stimuli are applied to a muscle at a sufficiently high frequency causing twitches to merge into higher forces.

Summation

The connective tissue sheath surrounding each muscle fasiculus.

Perimysium

Any muscle action that produces joint movement.

Dynamic contraction

The contractile element of skeletal muscle.

Myofibirls

Immature cells that can develop into mature cell types, such as myoblasts.

Satellite cells

An increase in size of existing individual muscle fibers.

Fiber hypertrophy

The "pumping up" of muscle that happens during a single exercise bout, resulting mainly from fluid accumulation in the interstitial and intracellular spaces of the muscle.

Transient hypertrophy

The loss of muscle mass associated with aging.

Sarcopenia

Loss of size, or mass, of body tissue.

Atrophy

Enzyme that controls the rate of protein synthesis within the myofibrils after resistance training.

mTOR

The initial energy required to start a chemical reaction or series of reactions.

Activation energy

The tearing down of body tissue, the destructive phase of metabolism.

Catabolism

The conversion of protein into glucose.

Gluconeogenesis

The process of turning a protein into a fatty acid.

Lipogenesis

An enzyme found early in a metabolic pathway that determines the rate of the pathway.

Rate limiting enzyme

The point during exercise of increasing intensity at which the end products of anaerobic glycolysis begins to accumulate above resting levels.

Lactate threshold

A series of chemical reactions that convert hydrogen ions from glycolysis and the Krebs cycle into water and produce energy for oxidative phosphorylation.

Electron transport chain

Cellular organelles that generate ATP through oxidative phosphorylation.

Mitochondria

The compound that forms the common entry point into the Krebs cycle for the aerobic breakdown of carbohydrate and fat.

Acetyl coenzyme A

The process of breaking down stored fats to its basic units to be used for energy.

Lipolysis

The body's most concentrated energy source and the form in which most fats are stored.

Triglycerides

The first step in fatty acid activation in which fatty acids are broken down into separate two carbon units.

Beta-oxidation

Which Krebs cycle intermediate, made from pyruvate, is of key importance in preventing dangerous ketoacidosis?

Oxaloacetate

A sensory receptor in a muscle tendon that monitors tension.

Golgi tendon organ

The junction between two neurons.

Synapse

The basic functional unit of a myofibril.

Sarcomere

Highest tension developed by a muscle in response to stimulation increasing in frequency.

Tetanus

Muscle shortening

Concentric contraction

Extensions of the sarcolemma (plasma membrane) that pass literally through the muscle fiber, allowing nutrients to be transported and nerve impulses to be transmitted rapidly to individual myofibrils.

T-tubules

Reflex inhibition of a motor neuron in response to excessive tension in the muscle fibers it supplies, as monitored by the Golgi tendon organ.

Autogenic inhibition

The conversion of glycogen to glucose.

Glycogenolysis

Soreness or pain felt immediately after an exercise bout.

Acute muscle soreness

A method of estimating energy expenditure by measuring respiratory gases.

Indirect calorimetry

Muscle soreness that develops a day or two after a heavy bout of exercise and that is associated with actual injury within the muscle.

Delayed onset muscle soreness

Which type of nervous receptor is sensitive to pain?

Nocioceptors

Which of these statements about the nervous system is NOT correct?

The sodium-potassium pump moves 3 sodium atoms out, and 2 potassium into the cell per ATP used

Depolarization is when the inside of the cell becomes less negative relative to the outside

Norepinephrine is secreted by pre-ganglionic neurons in the brain

The neuromuscular junction is a synapse between a neuron and a muscle cell.

Norepinephrine is secreted by pre-ganglionic neurons in the brain

Which statement is NOT true?

Training can alter the order of activation of type 1 and type 2 motor units

Training can alter neural precision

Training can alter neural endurance

Training can alter neural speed

Training can alter the order of activation of type 1 and type 2 motor units

The basic structural element of the nervous system is the _______.

Neuron

At rest, which ion is in the highest concentration outside of an excitable cell?

Sodium

An action potential is generated when a stimulus ___________.

Opens sodium channels

Put the following events in action potential in the correct order.

1. Action of Na+/K+ ATPase

2. The difference in the charge across the cell membrane becomes more negative

3. Opening of the potassium gates

4. The difference in the charge across the cell membrane becomes less negative

5. Opening of sodium gates due to stimulus

5,4,3,2,1

Activation of the sympathetic nervous system causes which of the following?

Release of T3

Catecholamine release from the adrenal medulla

Saltatory conduction

Increased usage of protein for energy

Catecholamine release from the adrenal medulla

_______ is the name for the chemical released from the terminal end of a neuron that binds to a specific receptor on the next cell in the sequence.

Neurotransmitter

Which of the following is NOT true about the human brain?

Humans only use 10% of their brain capacity

20% of daily energy expenditure is for brain function

The brain is included in the CNS

There is minimal evidence showing people are left or right brain dominant

Humans only use 10% of their brain capacity

The _____ is a functional portion of the nervous system that controls involuntary body functions.

Autonomic nervous system

Which of the following best describes the relationship between sympathetic nervous system activity and sports performance?

There is no relationship between sympathetic nervous activity and sports performance

A negative linear relationship, indicating that less sympathetic function increases performance

A positive linear relationship, indicating that more sympathetic function increases performance

An inverted U, indicating that too much or too little can be detrimental to performance

An inverted U, indicating that too much or too little can be detrimental to performance

______ is the propagation of action potentials along myelinated axons from one node of Ranvier to the next node.

Saltatory conduction

What does the size principle state about motor neuron recrutiment?

Small motor units are activated first when muscle force is required

Which of these is NOT true?

An IPSP makes it easier for the cell to be activated

Transport proteins regulate sodium and potassium movement across the cell membrane

The action of the sodium-potassium pump is an example of active transport, where something is moved against the concentration gradient

The imbalances in charges across the cell membrane results in the inside of the cell being -70mV compared to the outside

An IPSP makes it easier for the cell to be activated

Typically speaking, what is the threshold for a neuron to undergo an action potential?

-70mV

-95mV

-55mV

0mV

-55mV

Under which of these condition would you find the fastest rate of neural transmission?

Temperature of 39* C, pH 7.0, lots of myelin, larger axon diameter

What is the role of the Golgi tendon organ?

Monitor muscle tension

Which of these is NOT true about neurotransmitters?

Norepinephrine can cause different effects depending on whether it binds to an adrenergic or cholinergic receptor

Neurotransmitters can be measured with a blood test

After release from the vesicles, neurotransmitters can be degraded by enzymes

After release from the receptors, neurotransmitters can undergo reuptake in the releasing cell

Neurotransmitters can be measured from a blood test

Which of these statements is true?

Corpuscles sense things like touch and pressure

In response to strength training the EMG amplitude during maximal exercise is reduced

Activity of the parasympathetic nervous system will results in vasodilation of the coronary arteries

Serotonin causes feelings of sadness and dispair

Corpuscles sense things like touch and pressure

A depolarization of the post synaptic membrane caused by an excitatory stimulus.

Excitatory post-synaptic potential

A sensory receptor located in the muscle that senses how much the muscle is stretched.

Muscle spindle

Which of the following is NOT a characteristic of skeletal muscles?

Intercalated discs

Multinucleated

Voluntary control

Striated

Intercalated discs

During what speed of movement will a person be able to lift the heaviest weight?

A slow movement

In the figure showing muscle proteins, which protein does the arrow point to?

Myosin

Calcium ions responsible for turning on muscle contractions are stored in the ______.

Sarcoplasmic reticulum

During muscle contraction, which protein has the moving structures that pull on the others?

Myosin

Which of these is NOT true about skeletal muscles?

Muscle cells are also referred to as muscle fibers

Muscle cells require energy for both the action and relaxation phases of contraction

The individual muscle fibers within the skeletal muscle typically extend the entire length of the muscle

A motor neuron and all of the muscle fibers it innervates are referred to as a motor unit

The individual muscle fibers within the skeletal muscle typically extend the entire length of the muscle

Arrange the events leading to a muscle contraction in the correct order.

1. Release of calcium

2. Release of acetylcholine

3. Myosin binding to actin

4. Depolarization reaches the T-tubules

2,4,1,3

Which of the following is true?

Muscles carry out fine motor movements generally made up of motor units that contain only a few muscle fibers

A single motor neuron can innervate only one muscle fiber

The muscle-fiber composition of a a motor unit is generally mixed (type 1 and type 2 fibers)

A single muscle fiber may be innervated by multiple motor neurons

Muscles carry out fine motor movements generally made up of motor units that contain only a few muscle fibers.

Arrange the events of a muscle contraction in the right order.

1. Calcium binds to troponin, causing tropomyosin to move

2. Depolarization of the axon terminals

3. End plate potential in the muscle cell

4. The CNS sends a command in the form of a motor impulse

4,2,3,1

Which skeletal muscle fiber type has the lowest motor unit strength, the highest aerobic capacity, and the highest fatigue resistance?

Slow Oxidative

Which of these is NOT true about skeletal muscle fibers?

Myoglobin is the oxygen-transporting protein in muscles

FOG fibers are more fatigue resistant than type IIx

The reuptake of calcium from the sarcoplasm after contraction uses passive transport

Myoglobin gives slow-twitch muscles their dark red appearance

The reuptake of calcium from the sarcoplasm after contraction uses passive transport.

Which of these statements is NOT correct?

Cardiac muscle cells are striated

ATPase works with myosin to facilitate the power stroke of muscle contraction

Acetylcholine is the neurotransmitter between a motor neuron and a muscle fiber

Troponin covers actin binding sites on myosin

Troponin covers actin binding sites on myosin

The amount of force generated by a group of muscles depends on ________.

The type of motor units recruited, the number of motor units recruited, the frequency of stimulation of motor units

Which athletes would you expect to have the highest percentage of SO fibers in her body?

Paula Radcliffe, a world record holder in the marathon

Marion Jones, a world-class sprinter and jumper

Inge de Brujn, a world record holder for the 50m freestyle event in swimming

Gabriele Reinsch, a world record holder in discus

Paula Radcliffe, a world record holder in the marathon