Question

Describe how "cardiac function" is a physiological example that incorporates these pillars of physiology: homeostasis, energy, physics, autonomic nervous system and chemistry.

note: i'm not looking for a very very specific detailed answer! It can be related to these pillars in any way :)

Homeostasis:

Energy:

Physics:

Autonomic Nervous System:

Chemistry:

Answer 1

Cardiac function is a physiological example that incorporates various pillars of physiology like:-

Homeostasis: Heart is a major organ of maintaining body homeostasis because it generates the driving force for blood’s movement. It has to provide the required level of oxygen, nutrients, minerals to the different tissue. According to the activity of the tissue, the blood flow to that site is regulated to maintain the homeostasis. During high exercise, the heart has to send more blood to the skeletal muscle whereas the brain requires a constant amount of blood throughout. To maintain the balance the cardiac blood flow is also adjusted by controlling the blood pressure which is caused in response to various hormonal secretions.

Energy: Cardiac Function has a very high energy demand and to sustain the contractile function, the heart has to continually produce a large amount of ATP. The heart uses the food sources (carbohydrates, free fatty acids) for its energy whereas any less supply can cause damaged cardiac function due to cardiac muscle fatigue. Currently, it is studied that optimizing energy metabolism to the heart can be an important approach to treating various forms of heart disease.

Physics: Cardiovascular dynamics are highly governed by physics. The blood flow through the arteries, vessels strictly follows the rules of fluid dynamics. The rhythmicity of the heart is maintained by excitatory signals generated within the heart itself. The electrical impulse is generated by the S.A node which mainly causes the cardiac systole and diastole. The electrical and mechanical action of the heart is intensively studied and measured by electrocardiography (ECG). So physics is thoroughly related to cardiac functioning.

Autonomic Nervous System: The heart rate is controlled by to branch of the autonomic nervous system-

1) Sympathetic nervous system: The sympathetic nervous system releases the various hormones like catecholamines - epinephrine and norepinephrine to accelerate the heart rate by increasing cardiac muscle contraction.

2) Parasympathetic nervous system: The parasympathetic nervous system releases the hormone acetylcholine to slow the heart rate by decreasing the force of contraction of cardiac muscle.

Chemistry: Chemistry is a branch of science which is required for the study of all body physiology. In cardiac function, chemistry delineates how the cardiac cells metabolize food source to produce energy for its function. The nerves that coordinate the cardiac function sends the impulse to the cardiac muscle by the release of different neurotransmitters. The secretion of various hormones causes vasoconstriction or vasodilation to control the blood flow.