Which of the following had the job of slowing conduction of the impulses from the atria...

Which of the following had the job of slowing conduction of the impulses from the atria to the atria to contract and empty their blood volume into the ventricles?

Expert Solution

The conduction normally begins in the sinoatrial node (SA) node. It is located in the right atrial wall at the junction of superior vena cava and the right atrium. It is also referred as the primary pacemaker.
The pacemaker action potential from the SA node propagates throughout both atria via gap junctions in the intercalated discs of atrial muscle fibers. Following this the atria contract.
Then the impulses are passed through the AV node. AV node is a group of specialized muscle cells which is located near the tricuspid valve of the right atrium.
AV node delays the impulse of 0.1 seconds whereby the atria empties the blood completely before the ventricles contract.
Then the conduction enters the atrioventricular(AV) bundle (also known as the bundle of His), where the impulses conduct from atria to the ventricles.
The bundle of His divided into the right bundle (conducting to the right ventricle) and left bundle branches (conducting to the left ventricle) and extend through the interventricular septum toward the apex of the heart. Left bundle further bifurcates into left anterior and left posterior bundle branches and conduction system reaches the Purkinje fibers. At this stage, the ventricular contraction occurs which pushes blood upward toward the semilunar valves and forced blood either from the right ventricle (pulmonary circulation) or from the left ventricle (systematic circulation).

Note: In Normal circumstances, the SA node has the highest impulses of 40 - 60 per minute, and the AV node has the impulse rate of 30 - 40 per minute. If any malfunctions in the SA node then the AV node takes the function of pacemaker so the heart has a lower rate.

Nightingale answered 2 years ago

Describe the normal conduction of impulses through the heart.

describe the formation and conduction of a neural message (impulses).

52) both the left and right atria receive blood from: 53) which vessels vasoconstrict in response...

52) both the left and right atria receive blood from: 53) which vessels vasoconstrict in response to epinephrine and norepinephrine? 54) which of these periods represents greatest cardiac output? 55) contraction of the heart ventricles increases pressure in the chambers causing: 56) in the average person at rest how much blood moves through the heart each min? 57) which circuit has the greatest resistance?

Which of the following is required for nerve impulse conduction and is found in foods such...

Which of the following is required for nerve impulse conduction and is found in foods such as bananas, avocados, apricots, and potatoes? Question 26 options: A) Sodium B) Copper C) Chromium D) Potassium A severe deficiency of vitamin A may result in: Question 29 options: A) scurvy. B) Night blindness C) insufficient blood clotting. D) microcytic anemia In _____, too much adrenocorticotropic hormone is produced. Question 45 options: A) acromegaly B) cretinism C) Cushing's syndrome D) diabetes mellitus Physical reactions...

1. Which of the following DOES NOT influence the conduction velocity of an action potential A)...

1. Which of the following DOES NOT influence the conduction velocity of an action potential A) Diameter of the axon B) Permeability of the axon C) Density of Ca channels D) Myelination (answer not D or A) 2. The relationship of an action potential (AP) to the stimulus that generates it is best described as: A) Stimulus intensity is correlated with the frequency of the AP B) Stimulus intensity is proportional to the amplitude of the AP C) Stimulus intensity...

Which of the following is true regarding the conduction of electrical activity in the heart? Select...

Which of the following is true regarding the conduction of electrical activity in the heart? Select one: a. Conduction through the AV node is relatively slow b. The wave of depolarization travels directly from the atrial muscle to the ventricular muscle c. The AV node determines heart rate in a healthy person d. 2 of the above are correct e. None of the above are correct

In which area of the brain are the impulses interpret for each cranial nerve?

1) Which takes more work, slowing a car from 100km/h to 70km/h, or 70km/h to 0?...

1) Which takes more work, slowing a car from 100km/h to 70km/h, or 70km/h to 0? 2) A 0.2kg falcon flies at 50m/s toward a 0.01kg shrew moving at 0.2m/s away from the falcon. What is the total kinetic energy of the falcon-shrew system?

Motor nerve impulses pass from a neuron to a muscle cell ________. carried by neurotransmitters...

Motor nerve impulses pass from a neuron to a muscle cell ________. carried by neurotransmitters across neuromuscular junctions across a synapse using acetylcholine all of the choices Sarcomeres contain thin filaments of ________ and thick filaments of ________. fast fibers, slow fibers actin, myosin hemoglobin, myoglobin troponin, tropomyosin creatine, adenosine The muscular system consists of all the following EXCEPT sarcomeres myofillaments tendons Voluntary striated skeletal muscle fibers Voluntary smooth muscle cells Involuntary striated cardiac muscle fibers Skeletal muscle contractions...

During atrial fibrillation, what would be the result if all of the electrical impulses from the...

During atrial fibrillation, what would be the result if all of the electrical impulses from the atria were conducted through the AV node to the ventricles? How would it affect stroke volume? Cardiac output?

Question