Applied Anatomy Exam 2

Okstate Dr. J

What is the powerhouse of the cell?

Mitochondria.

What is a co-contraction?

Simultaneous contraction of agonist and antagonist muscles.

What's an eccentric contraction?

Muscle lengthens under tension.

What's a concentric contraction?

Muscle shortens while generating force.

What's an isometric contraction?

Muscle contracts but does not change length.

What is the SR, where do you find it?

Sarcoplasmic reticulum; found in muscle cells.

What's a sarcomere?

The basic contractile unit of muscle fibers.

What's a Golgi tendon organ and what does it do?

A proprioceptor that senses tension in muscle tendons.

What does a muscle spindle do?

It senses changes in muscle length and rate of stretch.

What part of the neuron can regenerate after injury?

Axon.

Where do you find the nodes of Ranvier?

Along myelinated axons.

What stimulates protein synthesis to make it grow?

resistance training, stretching (to a lower degree), steroids (muscles grow fast but not tendons; and premature growth plate closure)

What's another name for the somatic nervous system?

Voluntary nervous system.

Where do you find actin and myosin filaments?

In muscle fibers.

What's the fundamental of muscular function that includes neurons and individual muscle cells?

Motor unit.

The correct order in a muscle structure analysis

In descending order, Whole muscles, Fascicles containing muscle fibers (cells), Muscle fibers (cells) containing myofibrils, Myofibrils containing myofilaments, Myofilaments = Actin & Myosin, Actin contains Troponin & Tropomyosin, Myosin with cross bridges

What part of the nervous system is fight or flight?

Sympathetic nervous system.

Which part of the nervous system is rest and digest?

Parasympathetic

Which muscle fiber contains the greatest amount of mitochondria?

Type I (slow-twitch) muscle fibers.

What's a Z line?

The boundary between adjacent sarcomeres.

Where do you find I bands?

In the sarcomere, containing only thin filaments.

What is sarcopenia?

age related loss of strength and muscle mass

What is hyperplasia?

Increase in the number of muscle fibers.

Where do you find myelin?

Around some axons in the nervous system.

What is a refractory period?

The time after a stimulus during which a neuron is unable to respond.

What is resting potential?

The electrical potential of a neuron at rest.

What is polarization?

The state of a neuron when it is not transmitting an impulse.

What type of muscle cell has the greatest amount of glycogen enzymes?

Type II (fast-twitch) muscle fibers.

Where is calcium stored in the muscle cell?

sarcoplasmic reticulum.

What do the T-tubules do?

transmit action potentials into muscle fibers.

What is the terminal cisternae?

(ends of sr that touches t tube)- contains ca ions used in muscle contractions 

Identify the H zone.

The region in a sarcomere where only thick filaments are present.

What is the fascia that covers the whole nerve column called?

Epineurium.

What is affected by multiple sclerosis?

Myelin in the central nervous system.

What is rigor mortis?

Postmortem muscle stiffening due to lack of ATP.

What's excitability?

ability to receive and respond to stimuli

What is extensibility?

The ability of a muscle to stretch beyond normal length

What is elasticity in terms of muscle fiber?

The ability to return to original length after stretching.

What is synergistic action?

When 2 or more muscles act to produce a movement that 1 cannot perform alone

Where do you expect to find tropomyosin?

In the grooves of the actin filament.

What are Unipennate muscles?

Muscles with fibers on one side of a tendon.

What are Bipennate muscles?

Muscles with fibers on both sides of a central tendon.

What is another name for convergent muscle (structure)?

fan shaped muscles

What is a synaptic cleft?

The gap between a neuron and a muscle cell.

What is a synapse?

The junction between two neurons or a neuron and a muscle.

What is another name for an efferent neuron?

Motor neuron

What does Acetylcholine do?

It transmits nerve impulses to muscles.

What does acetylcholinesterase do?

It breaks down acetylcholine in the synaptic cleft.

What is the function of myelin?

To insulate axons and speed up nerve impulse transmission.

Where do you find smooth muscle?

In walls of hollow organs and blood vessels

Where does herpes lie dormant?

transported along nerves the skin then to the cell body, where it becomes latent and reside lifelong.

During resting state where do you find sodium and then calcium?

Sodium is outside the cell; calcium is in the SR

What is DOMS?

Delayed Onset Muscle Soreness.

What part of contraction actually contributes to DOMS?

Eccentric contractions.

What is a factor in force production of the muscle?

Fiber arrangement; Number of fibers/ type/ size of fibers

What does acetylcholinesterase do?

breaks down acetylcholine in the synaptic cleft

How does alcohol affect your nervous system?

It depresses central nervous system activity.

What is perimysium?

Dense irregular connective tissue surrounding a fascile (bundle) of muscle fibers

What is endomysium?

Dense irregular connective tissue surrounding individual muscle fibers.

What is osseous plasmic liquid in muscle cell?

Cytosol found in muscle cells.

Where is the ACSM recommendation for the frequency of resistance training during a week?

2-3 days per week.

What is tension in the muscle?

The force generated by muscle contraction.

How do you determine muscle fiber ratio (fast, slow)?

muscle biopsy

Where is myofibril hypertrophy and what causes it?

In muscle fibers; caused by resistance training (2-6 reps)

Where do you find Schwann cells and what do they do?

In the peripheral nervous system; they develop myelin.

What is the sliding filament theory and who contributed to it?

It explains muscle contraction; contributed by A.F. Huxley.

The I band contains only what type of myofilament?

Thin filaments (actin).

When do you experience fat cell hyperplasia?

During childhood and adolescence.

Why is a turkey drumstick dark compared to the breast?

Due to higher myoglobin and muscle fiber type.

Resistance training simulates which part of the fibers more than the others?

Type II (fast-twitch) fibers

What activates the knee jerk reflex?

Stretch of the quadriceps muscle, patellar tendon

What type of muscle tissue lacks striations?

Smooth muscle.

Where would you find a neurovascular bundle?

In peripheral nerves.

Which is an exteroceptor?

A sensory receptor that responds to external stimuli.

Survival question about stuck in snowy tent

If flame goes orange

Identify the Muscle cell (fiber)

In order, nucleus, transverse tubule, terminal cisterane of SR, sarcolemma, myofilbril, mitochondria, z line, a band, I band

Identify the Sarcomere

In order, I band, H zone, actin, M line, myosin, Z line, A band, Z to Z

Identify the Neuron

In order, axon terminal, dendrites, cell body, schwann’s cells, node of ranvier, axon, myelin sheath