In cardiac autorhythmic pacemaker cells, how does parasympathetic stimulation make it more difficultfor an action potential to occur?

Q: In what ways are autorhythmic fibers similar to and diff erent from contractile fibers?

A: Heart is a four chambered cardiovascular organ pumping blood throughout the body. The auricles and…

Q: What are Cardiac Action Potentials?

A: Unlike the action potential in skeletal muscle cells, the cardiac nerve impulse isn't initiated by…

Q: What is the mechanism behind the action potentials in the pacemaker cells?

A: A random, propagating, transitory and fast change of the muscle or nerve cell's resting membrane…

Q: Can the intraventricular septum prevents the electrical activity from stimulating the heart in a…

A: The intraventricular septum is present between two ventricles of the heart, generally preventing…

Q: In ECG, P and QRS waves represent what types of heart electrophysiological activity? Draw and speak.…

A: The circulatory patterns are of two types - open or closed. The open circulatory system is present…

Q: Describe two effects on the heart of sympathetic nervous system stimulation.

A: Introduction: The nervous system is categorized into the peripheral nervous system (PNS) and the…

Q: Why is it possible for acetylcholine to actually cause an increase in stroke volume, even though…

A: Acetylcholine is one of the most vital neurotransmitter in the human body, that is seen in both the…

Q: Describe the effect if the atria were to contract at thesame time as the ventricles, or if the…

A: The cardiovascular system is an organ system which distributes blood to all the parts of the body…

Q: If you were to look at an ECG trace of a 65-year-old male who has recently being diagnosed with a…

A: An electrocardiogram is used to records the electrical signals in our heart. It's a common and…

Q: What effect does standing still for a prolonged time haveon the blood pressure in the feet and in…

A: The heart purposely pumps blood at a particular pressure such that blood is able to flow against the…

Q: Fewer action potentials travel up the afferent nerves to the medullary cardiovascular center, and…

A: The cardiovascular center is part of the autonomic nervous system and is responsible for controlling…

Q: What are three of the ways in which cardiac muscle differsfrom skeletal muscle?

A: According to human anatomy, the muscular system is differentiated into three distinct types of…

Q: What prevents blood from flowing back into the ventricles whenthey relax?

A: The human heart is situated in the middle of the thoracic cavity in a space called the mediastinum.…

Q: Contrast action potentials in ventricular muscle cells with SA node action potentials.

A: A fast, sudden, propagating and transitory change of the muscle and nerve cell's resting membrane…

Q: Draw a ventricular muscle cell action potential.

A: The heart is a four chambered structure that is responsible for pumping the blood into the arteries…

Q: What causes the pacemaker cells of the SA node to trigger an action potential?

A: The heart is made up of cardiac muscle. It contains a network of specialized cardiac muscle fibres…

Q: Explain Graphic illustration of the position of a cardiac pacemaker?

A: The transportation of blood in the body is the function of the human circulatory system, also called…

Q: How does digitalis result in an increased contractile force of cardiac muscle?

A: The muscular system consists of three types- Smooth muscle Skeletal muscle Cardiac muscle Cardiac…

Q: If SA node (=natural pacemaker) fıring rate is 100 potentials per minute, but resting heart rate of…

A: Introduction: Some cardiac tissues are concerned with the initiation (impulse generation), and…

Q: During which two periods of the cardiac cycle do the heart muscle fibers exhibit isometric…

A: The cardiac cycle explains the cardiac event that occurs during the contraction and relaxation of…

Q: How is long refractory period beneficial for cardiac muscles?

A: Introduction: The heart is a muscular beating organ that transports deoxygenated blood to the lungs…

Q: A drug is found to partially inactivate fast sodium channels. Mow would this drug change the action…

A: Given: To find a drug that partially inactivate fast sodium channels. How it change the action…

Q: In a cardiac contractile cell what is the mechanism involved in the change in membrane potential?…

A: The cardiac contractile cell undergoes various changes in order to perform several activities and…

Q: Describe the structure of intercalated discs in cardiac musclecells, and briefly discuss their…

A: Cardiac muscle tissues are tissues of the heart and help to provide strength and flexibility from…

Q: we measured the stroke volume of the left ventricle. What was the average stroke volume of the right…

A: The circulatory system is one of the major systems of the human body. The circulatory system…

Q: What effect does an increase or a decrease inextracellular potassium, calcium, and sodium ions have…

A: Introduction: The blood comprises blood cells, namely red blood cells, white blood cells, platelets,…

Q: Your grandfather was told that his SA node (pacemaker) has stopped functioning. Explain how his…

A: The heart is a muscular organ that pumps blood through the blood vessels of the circulatory system…

Q: Why does the cardiac muscle have a longer absolute refractory period compared to skeletal muscle?

A: A cardiac muscle is a specialized type of muscle that forms the musculature of the heart. Just like…

Q: Describe isovolumetric ventriclar contraction in five steps

A: The cycle which includes one round of atrial contraction and ventricular relaxation is referred to…

Q: How does the depolarization of pacemaker cells differfrom the depolarization of other cardiac cells?…

A: Anatomy and physiology are the branches of biology, anatomy deals with the study of the structure of…

Q: What two structures directly receive an electrical impulse from the SA node?

A: Introduction: The sinoatrial node (SA node) is located on the heart's posterior region at the…

Q: cause of reflex tachycardia

A: TACHYCARDIA It is the medical which represents the fast heart rate. REFLEX TACHYCRDIA The reflex…

Q: What effect do you think this mutation will have on his heart rate compared tosomeone with a normal…

A: The heart is a four chambered structure that is responsible for pumping the blood into the arteries…

Q: A significant structural feature in the microscopic studyof cardiac muscle cells is the presence of…

A: The muscular system in our body plays an important role in producing movements The mobility of the…

Q: Atrial fibrillation can be caused by wandering re-entrant circuits.  What does this mean?

A: Introduction Any valve in the heart can be damaged or diseased, resulting in valvular heart disease.…

Q: In the following graphs of pacemaker potential recordings from the SA node, what graph represents…

A: Pacemaker potential is a action potential of SA nodes. Which has three phases- zero, three &…