ASCI 210: Exam 2

Traverse Tubules are located at the junction between the A band and I band overlap and assist in the suppression of electrical impulse from nerve to muscle fiber.

False (transmission of electrical impulse)

The sarcoplasmic reticulum regulates Na homeostasis and activation of myofibril contraction.

False (Regulates Ca)

The invaginations within the sarcolemma that assist in signal transduction are called Traverse Tubules.

True

Two terminal cisterna bisected by T Tubules compose what junction of the sarcoplasmic reticulum?

Triad Junction

The sarcolemma is considered the plasma membrane of the muscle fiber.

True

A motor unit is multiple motor neurons and all muscle fibers it innervates.

False (single motor neuron)

What are the two receptors that are responsible for the release of Ca through Ca releasing channels.

Dihydropyridine receptors

Ryanodine receptors

Which receptor is the ultimate regulator of Ca.

Dihydropyridine receptors

Which receptor controls the release of Ca into the sarcoplasm during E/C coupling.

Ryanodine Receptors

In the sarcomere during a state of rest myosin is in a cocked position and ATP is bound to the S2 neck region.

False (S1 globular head)

In the sarcomere, during a state of rest, Ca is bound to troponin.

False (not bound)

In the sarcomere, during a state of rest, the myosin binding site on actin is blocked by tropomyosin.

True

In the muscle, an AP stimulates the release of what ion?

Ca

Ca binds to Troponin I on the Troponin Complex.

False (Troponin C)

When Ca binds to Troponin C a conformational shift occurs. When that conformational shift occurs, what binding site is revealed.

Myosin binding site on actin.

During muscle contraction, the binding of actin and myosin creates what type of bond.

Actomyosin bond

When actin and myosin bind together, ATP gets hydrolysize from ATP to ADP and IP.

True

What breaks the actomyosin bond?

A new ATP binding to myosin.

In terms of the organization of a single whole muscle, the muscle itself is homogenous and the motor unit is heterogenous.

False (whole muscle=hetero and motor unit=homo)

The homogeneous aspects of a motor unit allows for our bodies muscle to adapt to changing demands.

True

What is not a change in a motor unit?

Change in fiber color.

Oxidative metabolism when glucose is converted to pyruvate.

False (converted to energy)

The conversion of glucose to glucose-6-phosphate requires which enzyme.

Hexokinase

During oxidative metabolism within a muscle cell, how much ATP is generated from one mole of glycogen?

31

The simplified function of cardiovascular system is to transport CO2 and nutrients and remove O2 and metabolic byproducts.

False (switch O2 and CO2)

Name the two circulatory series.

Pulmonary circulation

Systemic circulation

Which of the following is not a major division of the two circulatory series.

Expulsion

Arteries can be characterized as having strong thick walls with high elasticity.

True

Veins can be characterized as having no valves, no muscle, and no elasticity.

Veins are thin well and have valves with little elasticity.

Which statement does not describe the arterial system?

high volume/low pressure

The cardiac conduction system contains to functional cells responsible for heart contraction. What are they?

myocardial cells

pacemaker cells

Pacemaker cells have the ability to generate an AP without input from the nervous system.

True

At what voltage is the unstable resting potential of pacemaker cells?

\-60 mV

The membrane potential of pacemaker cells remains unstable due to unique ion channels what two ions are both permeable through those channels.

Na

K

What are the four primary pacemaker cells involved in the heart conduction?

AV Node

Sinoatrial Node

His Bundle

Purkinje Fibers

In the SA Node what is the inherent pace from the pacemaker potential.

70-80 PP/min

In the AV Node what does the inherent pace slow down to

40-60 PP/min

Of the four primary structures of the conduction system which divides the AV pacemaker potential into 2 lines of transmission through the interventricular septum.

His bundle

In the His bundle the impulse speed of transmission is sped up along with the pace (70-80n PP/min)

False (impulse sped up but pace stays the same)

Purkinje fibers are an extension of fibers throughout the two ventricles which allow for the further speedin gup speed of pacemaker potential and complete the stimulation of the ventricles.

True

The impulse from the VA notes is conducted across the atria when the right and left are depolarized both sides are stimulated and contract.

False (SA Node)

At AV node the pace of impulse is reduced allowing for a delay in transmission from the atrium to the ventricles.

True

A single complete cardiac cycle is made of 5 waves what are the waves?

PQRST

Which wave of the EKG represents atrial depolarization where the atriums contract.

P Wave

Which wave of the EKG represents the depolarization of the ventricles.

T Wave

Intrinsic regulation of the cardiac cycle is controlled by the myocardial cells.

False (pacemaker cells)

Name the two phases in the cardiac cycle.

Systole

Diastole

Systole is the relaxation phase.

False (Contraction phase)

Extrinsic regulation is controlled by the somatic nervous system.

False (controlled by ANS)

The sympathetic and enteric nervous system are the 2 division of the autonomic nervous system that have extrinsic affect on cardiac activity.

False (sympathetic and parasympathetic)

What are the 3 primary clusters of nerves within the brain.

Cardioaccelerator centers

cardioinhibitory centers

vasomotor centers

Where are the primaery clusters of nerves within the brain located?

Medulla oblongata

The cardioaccelerator center stimulates cardiac function via sympathetic stimulation.

True

The cardioinhibitory centers stimulates cardiac function via parasympathetic stimulation.

False (slows cardiac function)

Cholinergic neurons apart of the cardiovascular centers release what neurotransmitter?

ACh

Adrenergic neurons apart of the cardiovascular centers release what neurotransmitter.

Norepinephrine

The fight or flight response is triggered by the release of epinephrine and norepinephrine from the adrenal medulla, the result is…

an increased heart rate

temporary constriction of blood vessels

redirection of blood to liver skeletal muscle and heart

The general function of respiration is the exchange of gases within the environment which involves the delivery of O2 and the removal of CO2.

True

Cellular respiration is the anaerobic breakdown of pyruvic acid to ATP.

False (aerobic breakdown)

Red blood cells have a nucleus.

False (no nucleus)

Which of the following is not an advantage to having the discocyte shape as characterized by red blood cells.

easy to stack onto each other

Hemoglobin is the principal component of a red blood cell which of the following is a characteristic of hemoglobin.

large polypeptide chain

four heme groups

responsible for binding O2 and CO2

In the heme group the Fe3 (ferric) subunit is responsible for binding to O2.

False (Fe3 ferric binds CO2) (Fe2 ferrous binds O2)

Which of the following is an additional function of the respiratory system.

Ventilation

Olfactory

Phonation

Regulation of blood pH

The respiratory cycles consist of two phases. What are they?

Inspiration

Expiration

Inspiration is the reduction of the thorax and lungs, with an accompanying outflow of air.

False (expiration)

The inspiratory and expiration cycle is smooth and symmetrical for most animals. Which animal does not have a smooth and symmetrical inspiration and expiration cycle.

Horse

What are the two zones of the tracheobronical tree.

Conducting

Respiratory

Of the four different pulmonary volumes which pulmonary volume refers to the amount of air, breathed in and out during a single respiratory cycle.

Tidal volume

Of the four different pulmonary volumes which pulmonary volume refers to the amount of air remaining after forceful expiration.

reserve volume

The difference in barometric pressure (atmosphere) compared to intrapleural pressure (pressure within plural sac) defines what

Pressure gradient

Based on the principles of boyles law pressure is directly proportional to volume.

False (indirectly)

If teh volume increases pressure will

decrease

During inspiration lowering the diaphragm reduces pressure on teh lungs which well increase lung volume.

True

During expiration raising the diaphragm increases the pressure on the lungs which will decrease lung volume.

True

Wehre does the primary site of exchange of gases in the lungs

alveoli

Gas exchange in the alveoli is based upon what form of diffusion

simple

Simple diffusion is defined as the movement of a solute in a solution from high concentrations to low concentrations

True

Both O2 and CO2 diffuse across the respiratory membrane through simple transport.

False (passive transport)

The simplistic definition of Frick’s law is that gasses always move from a region of high partial pressure to a region of low partial pressure.

True

What percentage of oxygen is transported within red blood cells

98%

Each red blood cell can carry 3 molecules of O2

False (4)

What are the two hemoglobin isoforms?

oxyhemoglobin

carbanimohemoglobin

What is not a form of CO2 observed within the circulatory system?

CO