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Coaductile pathway, Timing of contraction signal & Conduction system and ECG

By: HWC, Views: 7941

• When the system is healthy, the signal to contract the entire conduction system originates in the SA node - known as the heart's pacemaker. • The SA node triggers contraction because it depolarizes at a faster rate than other parts of the conduction system. • The wave of excitation fr...

Hormonal regulation of blood pressure - RAA system

By: HWC, Views: 8172

■ Long-term regulation of MABP is under hormonal control. • Hormones that affect blood pressure and volume: the renin-angiotensin-aldosterone (RAA) system, antidiuretic hormone (ADM), and atrial natriuretic peptide (ANP). ■ Most important hormonal regulator of MABP. Activated by drop in...

Components of the Nervous System

By: Administrator, Views: 435

The nervous system is the part of an animal that coordinates its actions by transmitting signals to and from different parts of its body. The nervous system detects environmental changes that impact the body, then works in tandem with the endocrine system to respond to such events. Nervous tissue...

Depolarization of the SA node, Action potentials of the myocardium & ANS effects

By: HWC, Views: 7635

• A typical contractile cell in the myocardium has a resting membrane potential. • The resting membrane potential of cells in the SA node is not fixed, and is known as the pacemaker potential. • The action potential of a healthy SA nodal cell has three parts: • Pacemaker potential: ...

Ventilation - phases and driving forces

By: HWC, Views: 7810

Respiration is the exchange of gases between the atmosphere, blood, and cells The combination of 3 processes is required for respiration to occur Ventilation (breathing) External (pulmonary) respiration Internal (tissue) respiration The cardiovascular system assists the respiratory system b...

Epinephrine/NE (heart rate, altered blood flow, glycogenolysis & bronchodilation)

By: HWC, Views: 7677

• Stressors trigger increased sympathetic stimulation from the hypothalamus to the chromaffin cells of the adrenal medulla. • This causes the immediate release of epinephrine and norepinephrine (NE). • Epinephrine/NE binds to the cardiac muscles of the heart. • Cardiac muscle cells ...

baroreceptors

By: HWC, Views: 7494

A baroreceptor is a specialized nerve ending that allows your brain to sense blood flow and blood pressure in the major blood vessels of your circulatory system. • The aortic arch carries blood to the body. • The common carotids carry blood to the head. • Baroreceptors measure chang...

Functional zones in a mitochondrion

By: HWC, Views: 5677

A mitochondrion has a double membrane system. The outer membrane faces the cytoplasm. The inner membrane divides the organelles interior into two compartments. The enzymes that carry out the second stage reactions are in the semifluid matrix inside the inner compartment. Embedded in the ...

Morphology of a tomato plant

By: HWC, Views: 2260

The bulk of the plant body is comprised of ground tissue. Vascular tissue threads through the ground tissue. It distributes water, solutes, and organic substances through the plant body. Dermal tissue covers and protects the surfaces of the root and shoot systems.