Physiology Chapter: Nervous & Cardiac Systems

High systolic blood pressure (SBP) but normal diastolic blood pressure (DBP).

Difference between systolic and diastolic blood pressure.

Brain and spinal cord.

Nerves that connect to limbs and organs.

Carries signals to the CNS.

Carries signals from the CNS.

Controls involuntary functions (e.g., heart rate).

Controls voluntary movements (e.g., walking).

Nerve fibers in the autonomic nervous system that connect to postganglionic fibers at ganglia.

Nerve fibers in the autonomic nervous system that connect to organs or glands.

Clusters of cell bodies where preganglionic and postganglionic fibers connect.

Chemical messengers that transmit nerve signals across synapses.

Part of the nervous system controlling involuntary functions like heart rate.

One of the two divisions of the autonomic nervous system, often associated with rest and digest functions

The other division of the autonomic nervous system, often associated with fight-or-flight responses.

Carries signals from the central nervous system to organs, such as heart.

The process of creating catecholamines (like dopamine and norepinephrine) within neurons.

The amino acid that is the precursor for catecholamine synthesis.

A catecholamine produced in dopaminergic neurons, often in the brain.

A catecholamine produced in many sympathetic neurons.

A catecholamine derived from norepinephrine in some cases.

The complex series of chemical reactions to synthesize catecholamines.

The process of neurotransmitter vesicles merging with the exterior membrane of the neuron.

The process of destroying or removing catecholamines from the synapse.

Mechanisms that maintain stable blood pressure despite changes in variables.

Mechanisms that rapidly adjust blood pressure, primarily by altering peripheral resistance and cardiac output.

Cluster of neurons in medulla controlling blood vessel diameter via vasoconstriction/vasodilation.

Neural receptors in aortic arch and major arteries sensitive to blood pressure changes.

Mechanisms that adjust blood volume (and thus blood pressure) over time.

Opposition to blood flow in the blood vessels.

Narrowing of blood vessels.

Amount of blood pumped by the heart per minute.

Bulbous swellings along nerve fibres, containing neurotransmitter vesicles, innervating smooth muscle.

Slow, synchronized contractions of sheets of smooth muscle cells connected by gap junctions.

Mechanism of smooth muscle contraction, where thin filaments slide over thick filaments.

Made of actin polymers, crucial in smooth muscle contraction

Composed of myosin molecules, lying lengthwise and having cross-bridges.

Myosin heads with actin-binding and ATPase sites, crucial for muscle contraction.

Takes longer (10-30 times) than skeletal muscle contraction and can maintain tension without fatigue.

Crucial for smooth muscle contraction; their permeability increases by various means.They are in plasma membranes and sarcoplasmic reticulum

Problems with the part of the nervous system that controls involuntary functions, potentially leading to high blood pressure.

A type of receptor that plays a role in controlling blood pressure when stimulated.

Problems with the baroreceptors, sensors that detect blood pressure changes, can lead to blood pressure problems.

Specific parts of the brain can be over-stimulated, leading to increased blood pressure.

A system in the body that regulates blood pressure and fluid balance, that can be activated in a way to cause excessive pressure.

Narrowing of blood vessels, often leading to increased blood pressure.

The heart is pumping blood faster and/or with more force, pushing more blood through vessels, leading to increased blood pressure

Blood vessels are constricted (narrowed). This causes blood flow to be more challenging (increased resistance), thereby influencing blood pressure.

A clear, specific statement outlining what you aim to achieve, including measurable outcomes, timeframes, and relevance to goals.

Objectives that are Specific, Measurable, Achievable, Relevant, and Time-bound.

Quantifiable measures that track progress towards achieving an objective.

Obstacles or difficulties that might arise while working towards an objective.

Periodic assessments of progress made towards objectives, allowing for adjustments and course corrections.

Objectives clearly state the exact action or outcome to be achieved, avoiding ambiguity.

Objectives incorporate metrics to track progress and evaluate success, often involving quantifiable data.

Objectives are realistic and attainable given available resources, timelines, and constraints.

Objectives align directly with the overall project goals and priorities.

Objectives include a defined timeframe or deadline for completion or achieving results.

Well-defined objectives provide clarity for all stakeholders, ensuring everyone understands the intended outcomes.

Objectives act as benchmarks for evaluating progress and success, clearly outlining criteria for success or failure.

Cardiac output (CO) is the amount of blood pumped by the heart per minute. It is calculated by multiplying the heart rate (HR) by the stroke volume (SV): CO = HR x SV

Cardiac output increases when either the heart rate or stroke volume increases.

MAP is the average pressure in the arteries during a single cardiac cycle. It is calculated by: MAP = Diastolic Pressure + 1/3(Systolic Pressure - Diastolic Pressure)

MAP is primarily influenced by cardiac output and total peripheral resistance (TPR). Higher CO or TPR increases MAP.

The valve located between the right atrium and right ventricle. It prevents backflow of blood from the ventricle into the atrium during ventricular contraction.

The chamber of the heart that receives oxygenated blood from the lungs. This blood then passes to the left ventricle.

During ventricular systole (contraction), the aortic and pulmonary semilunar valves open to allow blood to be ejected into the aorta and pulmonary artery.

This phase happens at the beginning of ventricular contraction. All heart valves are closed, and ventricular pressure rises as the muscles contract, but no blood is ejected yet.

Total Peripheral Resistance: the overall resistance to blood flow in the circulatory system.

Widening of small arteries, reducing resistance to blood flow.

Increases heart rate and constricts blood vessels, causing increased blood pressure.

Slows heart rate and promotes vasodilation, decreasing blood pressure.

High blood pressure without a known underlying cause, often linked to lifestyle factors.

High blood pressure caused by a specific underlying condition.

Indicates increased arterial stiffness and higher risk of cardiovascular problems.

If cardiac output increases while TPR remains constant, MAP (Mean Arterial Pressure) also increases proportionally.

MAP (Mean Arterial Pressure) = Cardiac Output x Total Peripheral Resistance

Impaired function of the inner lining of blood vessels, contributing to high blood pressure.

Contribute to hypertension by promoting vasoconstriction and inflammation.

Nitric oxide relaxes vascular smooth muscle, causing vasodilation and reduced blood pressure.

The enzyme responsible for producing nitric oxide in endothelial cells.

Causes vasoconstriction and increased total peripheral resistance, raising blood pressure.

The division of the autonomic nervous system that activates the 'fight or flight' response. It increases heart rate, contractility, and bronchodilation. It causes vasoconstriction in non-essential tissues and vasodilation in skeletal muscle.

The division of the autonomic nervous system that promotes 'rest and digest' activities. It slows heart rate, increases digestive secretions, enhances intestinal motility, and facilitates urination.

Calcium binds to calmodulin, forming a calcium-calmodulin complex. This activates myosin light chain kinase (MLCK), which phosphorylates myosin, enabling actin-myosin interaction and contraction. Smooth muscle contraction is terminated when calcium levels decrease, allowing dephosphorylation of myosin by myosin light chain phosphatase.

The initial stretch of ventricular myocardium caused by end-diastolic volume (EDV). Increased preload enhances stroke volume via the Frank-Starling mechanism.

The resistance the heart must overcome to eject blood (e.g., aortic pressure). Increased afterload reduces stroke volume by increasing end-systolic volume (ESV).

The Frank-Starling Law states that the force of contraction is proportional to the initial length (stretch) of cardiac muscle fibers. Increased venous return enhances EDV, stretching fibers and increasing stroke volume up to a physiological limit.

The thickness or stickiness of blood. Higher viscosity increases resistance to blood flow.

Narrower vessels offer greater resistance to blood flow. Wider vessels allow easier blood flow with less resistance.

The longer the blood vessel, the greater the resistance to blood flow. This is because blood has to travel further, encountering more friction.

The smaller the diameter of a blood vessel, the greater the resistance to blood flow. This is because the blood has less space to move through.

A hormonal system that regulates blood pressure and fluid balance. It is activated when blood pressure or sodium levels decrease, causing vasoconstriction and water retention.

A powerful vasoconstrictor that increases blood pressure by narrowing blood vessels. It also stimulates the release of aldosterone, which promotes water retention.

The cells that line the inside of blood vessels. They release substances that regulate vascular tone, controlling the diameter of blood vessels.

A vasodilator released by endothelial cells that relaxes smooth muscle, widening blood vessels and reducing blood pressure.

The volume of blood pumped by the heart per minute. It is calculated by multiplying heart rate by stroke volume.

The overall resistance to blood flow in the circulatory system, primarily influenced by the diameter of arterioles.

A persistent blood pressure reading of 140/90 mmHg or higher. It is a major risk factor for heart disease, stroke, and kidney failure.

A condition where the inner lining of blood vessels is damaged, leading to reduced NO production, increased vasoconstriction, and increased risk of hypertension.

The heart pumps more strongly when it's filled with more blood. Like a stretched rubber band, the heart can contract more forcefully.

Calcium triggers smooth muscle contraction by activating a protein that allows muscle fibers to slide past each other

The thickening of the left ventricle wall, a result of the heart working harder to pump blood against increased resistance due to hypertension.

When the heart can't pump blood efficiently due to damage from chronic hypertension.

Damage to the brain from a blocked or ruptured blood vessel, potentially caused by hypertension.

A long-term condition where the kidneys don't filter waste properly, often linked to hypertension.

A bulging or weakened area in a blood vessel, potentially caused by hypertension.

Damage to the walls of arteries due to chronic high pressure, leading to hardening and narrowing of vessels.

Receptors in the sympathetic nervous system primarily responsible for inhibiting the release of norepinephrine, which helps regulate blood pressure.

Receptors in the sympathetic nervous system that increase heart rate, contractility, and release of the hormone renin, all of which raise blood pressure.