A & P test 4

Glycolysis

Which ATP production in skeletal muscle is in the cytosol?

Aerobic cellular respiration

Which ATP production in skeletal muscle is found in the mitochondria?

Anaerobic

Is glycolysis anaerobic or aerobic?

Creatine Kinase

_______________ is used in both the cytosol and the mitochondria to catalyze the formation of ATP from ADP and Pi

Creatine phosphate

Creatine kinase requires the use of ______________ to make ATP

Aerobic

Is cellular respiration anaerobic or aerobic?

glucose

Glycolysis requires _______

O2

Oxidative phosphorylation requires ___________

glucose

What is the preferred fuel of oxidative phosphorylation is __________

ADP, ATP

Stored ATP is first taken up for immediate use making an _______ which is then used with a creatine phosphate to make an ______ and then the cycle keeps going

blood vessels

Glucose in the ___________ are used to undergo glycolysis

2 ATP

Glycolysis breaks down each glucose molecule to produce ______

pyruvate

Glycolysis makes a _________ which is oxidized to go through cellular respiration in the mitochondria to make many ATP

Glycogen

___________ (storage form of glucose) is found in muscle

diet

Glucose comes from our _______

air

Oxygen comes from ______

Myoglobin

___________ in muscles is an oxygen-binding protein, “sink” for oxygen

Stored, Creatine Phosphate, Glycolysis, Aerobic mitochondria

Name the order in which energy sources are used:

fatigue

____________: decrease in the ability to produce force (even if muscle is still receiving neuronal input)

ATPase

Speed of contraction depends on how fast the __________ in the myosin head can hydrolyze ATP into ADP and phosphate

pathways

Duration of contraction depends on _________ for making ATP

Muscle hypertrophy

_____________: muscle getting bigger

Atrophy

__________: No growth/ shrinkage

Endurance training

_____________:

-Aerobic

-Increase frequency of motor unit activation

-Smaller increase in force production

Result: increased blood vessels, mitochondria

Resistance training

_______________:

-Anaerobic

-Increased frequency of motor unit activation (to a small extent)

-Large increase in force production

Result: increased diameter of muscle fibers and myofibrils

Astrocytes

(CNS glial cells)

-Control the physical and chemical environment of the neurons

Microglia

(CNS glial cells)

-Clean up the environment

Ependymal cells

Make CSF

Oligodendrocytes

Make myelin sheath

Schwann cells

___________ produce myelin

Satellite cell

_________________ are sort of analogous to the astrocytes of the CNA, control the environment around neurons

Sensory, motor, and interneurons

What are the three functional classifications for neurons?

Biology of neurons:

Extreme longevity, high metabolic rate

passive

Movement through ion channels is ___________

Synapse

Communication between two neurons happens at the _________

EPSPs

Depolarization of post synaptic membrane

IPSPs

Hyper polarization of post-synaptic membrane

Absolute refractory period, relative refractory period

Which refractory period goes first and then second?

Myelin, Axon diameter

What two things affect speed of action potential propagation?

Saltatory conduction

______________ in axons covered with myelin sheaths

Continuous conduction

___________ in non-myelinated axons

Sarcomeres

Each myofibril is made up of ___________

thick and thin

Sarcomeres have ___________ filaments

Thick filaments

___________ are made of myosin proteins

Thin filaments

______________ are composed of actin, tropomyosin and troponin

tropomyosin

When the muscle isn’t stimulated to contract, the binding sites are covered by __________

calcium

Myosin-binding sites are exposed when __________ ions bind to troponin during excitation-contraction coupling

band

A ___________ in sarcomere is the region occupied by thick filaments

M line

The thick filaments are anchored to the __________

Center

The M line marks the _______ of the sarcomere

slide

Muscle contraction occurs as thin filaments ________ past thick filaments toward center (M line)

z line

Sarcomere is shortened because it pulls the ________ toward the center

cross bridges

Once the ____________ form, myosin pulls the thin filaments towards the center of sarcomere

Cross bridge formation, power stroke, cross bridge detachment, reactivation of myosin head

Cross bridge cycle:

high

When excitation-contraction coupling causes the myosin binding sites on actin to be exposed, myosin starts in _______ energy state

ADP

At first ATP binding site on myosin head is occupied by ______

pivot

When the inorganic phosphate is released from the myosin head it causes the head to ________, pulling the thin filament toward the center

ATP hydrolysis

_____________ “cocks” the myosin head because there is energy release which reactivates the myosin

Muscle relaxation

_______________ occurs when the calcium ion concentration drops below its threshold value for binding to troponin

Neuromuscular

____________ junction triggers muscle contraction

Acetylcholine

When an action potential fires from a motor neuron, ___________ is released into the synaptic cleft

ligand gated

Acetylcholine then binds to receptor of ___________ channel on sarcolemma (motor end plate)

sodium

When acetylcholine binds and opens ligand-gated channels, __________ rushes into the muscle cell and the end plate stimulates an action potential.

potassium

After sodium rushes into the cells, __________ voltage-gated channels then open and positive ________ ions leave the cell, making the membrane potential more negative

T-tubules

The action potential in the motor plates are propagated down the ________

sarcoplasmic reticulum

T-tubule depolarization leads to the opening of calcium channels in the _____________ and calcium enters the cytosol

endomysium

Sarcomeres contract, transmitting tension to the sarcolemma and __________

perimysium

The tension of the muscle fibers is transmitted to the fascicle and ______

pulling

The tension in the fascicles is transmitted to the connective tissues of the whole muscle, including tendons, leading to the ________ on the bones and causing movement

Fascicle

bundle of muscle fibers

myogram

laboratory record of contractile activity

Twitch

motor units response to a single AP from motor neuron

slow succession

An action potential is in _____________, if muscle fibers have time to relax before they are stimulated to contract again

An action potential is in ___________, if relaxation time between twitches becomes shorter (or muscle may not relax completely)

rapid succession

Unfused tetanus

Tetanus?= If more stimulus is applied before the muscle relaxes completely, then more tension results

-Muscle fibers partially relax between contractions

Fused tetanus

Tetanus? = At higher stimulus frequencies, there is no relaxation between stimuli

Recruitment

Multiple motor unit summation

Subthreshold stimulus

Stimulus that has no observed muscle organ contractions produced

Threshold stimulus

Stimulus that has observable contraction and muscle organ contraction occurs

Maximal stimulus

Strongest stimulus that increases contractile force

-At this point all of the muscles motor units are recruited

increases

The strength of muscle contraction ___________ as stimulus increases until the maximal stimulus

The size principle of recruitment

-The first motor unit recruits small fibers

-The second motor unit recruit the medium fibers next

-The third motor unit recruits large fibers last

number of cross-bridges

The ______________ that can form in a sarcomere will affect the amount of tension that can be produced

Isotonic concentric contraction

-Muscle shortens

-On stimulation, muscle develops enough force to lift the load (weight)

-Force generated by the muscle is greater than the external load

Isotonic eccentric contraction

-Muscle lengthens

-On stimulation, muscle develops tension. But the force generated by the muscle is less than the external load

-The weight is stretching the muscle

Isometric contraction

-Muscle stays the same length

-Muscle is attached to a weight that exceeds the muscle’s peak tension (force) developing capabilities

_resistance of the load to movement is not overcome, load does not move