Nervous System: Central, Peripheral, and Autonomic

Intersystem Communication + Nervous System

• All systems work to keep the body running smoothly.
• The Central Nervous System and Peripheral Nervous System control movement, reflexes, and balance.
• The central nervous system consists of the brain and spinal cord.
• The peripheral nervous system includes the other nerves.
• The Somatic System controls voluntary movements and is part of the peripheral nervous system.
• The Autonomic System manages involuntary actions like heart rate, breathing, and digestion.
• The sympathetic network activates the "fight-or-flight" response.
• The parasympathetic network helps the body relax and maintain essential functions.
• Proprioceptors sense body position and movement.
• Baroreceptors detect changes in blood pressure and volume.
• Chemoreceptors in the carotid body and aortic arch sense changes in oxygen, carbon dioxide, and pH levels in the blood.
• Intrinsic cardiac functions happen within the heart, like the SA Node, which is the heart's natural pacemaker
• Extrinsic include neural and hormonal actions outside of the heart.
• During aerobic respiration, oxygen and glucose turn into CO2 and H2O; this process is followed by the ATP equation.
• Receptors like proprioceptors, baroreceptors, and chemoreceptors send signals via the Nervous System to effectors.
• Proprioceptors are located in muscles, tendons, and joints.
• Baroreceptors sit in carotid arteries and the aortic arch, adjusting heart rate based on blood pressure.
• Chemoreceptors in the carotid, aorta, and brainstem adjust breathing rate based on blood oxygen and carbon dioxide levels.

Cardiac Functions

• Intrinsic and extrinsic functions control the heart, altering things based on the environment and system regulations.
• Frank-Starling Law explains that an increase in blood causes the heart to stretch more.

Autonomic Systems

• The Somatic and autonomic systems manage voluntary versus involuntary actions together.
• The sympathetic system increases heart rate and blood flow to muscles, while slowing down digestion, the parasympathetic vice versa.

Endocrine System

• The endocrine system is a network of glands that produce hormones and release them into the bloodstream.
• These hormones regulate metabolism, energy use, and recovery.
• Hormones come from glands.
• The nervous system detects changes and communicates with glands to find a solution.
• Epinephrine and Norepinephrine (adrenaline), from adrenal glands, raises heart rate and uses more energy by using glucose.

Hormone levels

• Insulin and Glucagon both control blood sugar levels: insulin lowers it, helping muscle recovery, and glucagon raises it by breaking down glycogen.
• Antidiuretic hormone, from the pituitary gland, reduces urine and water loss to prevent drying out and helps to balance fluids.
• Reproductive hormones (testosterone and estrogen) affect muscle growth, endurance, and recovery, as well as metabolism.
• Progesterone is a thermoregulation hormone from the reproductive group that affects fuelling and sleep.
• Oestrogen promotes glycogen sparing for fat use and improves female endurance and flexibility.

Explore the nervous system's structure and function. Learn about the central and peripheral nervous systems, including the somatic and autonomic systems. Discover how these systems control movement, reflexes, and involuntary actions, maintaining homeostasis.