1. The heart exhibits auto-rhythmicity as the impulse for its rhythmic contractions originates internally, a characteristic known as myogenicity. 2. Certain cardiac muscle fibers acquire self-excitability during development, contributing to the generation of impulses. 3. These self-excitable fibers serve crucial roles as pacemakers, establishing the heart’s rhythm. 4. Additionally, they constitute a conductive system facilitating … Read more
1. Closed circulation significantly boosts the speed, precision, and efficiency of blood flow, allowing for faster circulation through the closed system and quicker return to the heart. 2. In open circulation, lacking dedicated blood vessels like arteries or veins, there is a resulting low blood pressure, contrasting with the heightened efficiency of closed circulation.
1. Cardiac Output: A typical cardiac output is 5 liters per minute. Elevated cardiac output correlates with an increase in systolic pressure. 2. Peripheral Resistance: The resistance in peripheral vessels hinges on their diameter. Vasoconstriction induced by vasopressin results in heightened peripheral resistance, leading to an elevation in blood pressure. 3. Blood Volume: Traumatic blood … Read more
Papillary muscles form prominent ridges in ventricles. Bicuspid and tricuspid valves connect to these muscles via chordae tendinae. Chordae tendinae are inelastic fibers within ventricles. They prevent valve reversal into atria during ventricular contraction, controlling valve opening and closing. The intricate system ensures proper heart function.
1. Tricuspid Valve: – Location: Junction of right atrium and right ventricle. – Function: Opens for blood flow from right atrium to right ventricle. 2. Pulmonary Valve: – Location: Right ventricle and pulmonary artery. – Function: Opens for blood flow from right ventricle to lungs. 3. Bicuspid Valve (Mitral Valve): – Location: Left atrium. – … Read more
1. The heart is positioned on the left side of the chest within a fluid-filled space called the pericardial cavity. 2. This cavity is enveloped by a protective membrane known as the pericardium. 3. The pericardium, a fibrous membrane, serves as an external covering for the heart. 4. Its primary function is to safeguard the … Read more
Blood clotting, also known as coagulation, is a crucial mechanism that prevents excessive bleeding when a blood vessel is damaged. Platelets, a type of blood cell, collaborate with proteins in the plasma (the liquid component of blood) to form a clot, effectively halting the bleeding at the site of injury. The process of blood clotting … Read more
1.Plasma, constituting the straw-colored, slightly alkaline, and viscous component of blood, comprises 90-92% water and 8-10% soluble proteins. Among these proteins, such as serum albumin, serum globulin, heparin, fibrinogen, and prothrombin, collectively make up 7% of the plasma, contributing to its crucial physiological functions. 2.Furthermore, plasma serves as a carrier for essential nutrients like glucose, … Read more
Sneezing involves the involuntary contraction of expiratory muscles, leading to a forceful release of air through the nose and mouth.
B. A respiratory surface area should be kept dry Correct statement: It is essential to maintain moisture on a respiratory surface.