The human circulatory system consists of a muscular four-chambered heart, a network of closed branching blood vessels and blood, the fluid which is circulated. The heart is mesodermal in origin. It is situated in the thoracic cavity, in between the two lungs. The heart is slightly tilted towards the left side because the right lung is larger than the left lung. This condition provides the heart with enough space to function properly and pump blood efficiently to different parts of the body.

The force with which the blood pushes against the walls of the blood vessels, usually arteries, is known as the blood pressure. It is described in the unit mm Hg. The normal diastolic and systolic pressure of the adult human heart is 120 mm Hg and 80 mm Hg, respectively.

Thus, the correct answer is 'Pushes against wall of blood vessels.'

Flow of blood through vasa recta follows counter current pattern. Filtrate flows through loop of Henle.

Aldosterone is secreted by the outer layer of the adrenal gland. When aldosterone is present in the blood, all the $Na^{+}$ in the filtrate is reabsorbed b the epithelial cells of DCT and collecting duct. Retaining $Na{+}$ raises the osmotic pressure of the blood and reduces water loss from the body. 

A) The contraction phase of the heart is called systole.

A) Blood pressure is always read as systolic/diastolic pressure. Systolic pressure is 120 mm Hg while diastolic pressure is 80 mm Hg.

• The increasing of the concentration of Sodium ions in blood would attract water from the surrounding issues, because of the osmotic pressure.

The diastole phase is the phase of relaxation where the chambers of the heart relax and blood fills into the respective chambers. The systolic phase is the phase of contraction. The normal systolic pressure is about 120 mm Hg & diastole pressure is 80 mm Hg.

The diastole phase is the phase of relaxation where the chambers of the heart relax and blood fills into the respective chambers. The systolic phase is the phase of contraction. The normal systolic pressure is about 120 mm Hg & diastole pressure is 80 mm Hg. So, the correct answer is option B.

Blood pressure is measured in 2 categories, systolic blood pressure and diastolic blood pressure. The systolic pressure is the amount of pressure in the arteries during the contraction of the heart muscle. The diastolic pressure is the pressure during the resting period between heartbeats. The normal value of systolic pressure in human is 120 mm of Hg. The normal value of diastolic pressure in human is 80 mm of Hg.

Blood pressure is the pressure of the circulating blood against the walls of the arteries, the veins, and the chambers of the heart. The blood pressure in the large artery of the heart, the aorta, and the other large arteries of a healthy adult is usually 120 mm Hg during the contraction of the heart (systole), and 80 mm Hg during relaxation of the heart (diastole). Normal blood pressure is less than 120/80 mm Hg. So, the correct answer is-120/80 mm Hg.

• Vasopressin regulates the tonicity of body fluids. It is released from the posterior pituitary in response to hypertonicity and causes the kidneys to reabsorb solute-free water and return it to the circulation from the tubules of the nephron, thus returning the tonicity of the body fluids toward normal.
  
• If vasopressin receptors are absent, it would result in increased loss of water from the body, leading to dehydration, increased thirst and Increased blood pressure.

High blood pressure can cause serious medical problems. Reacting to stress in high blood pressure can increase the risk of heart attacks and strokes due to the increase of blood flow in blood vessels. So, to avoid stress is one of the precautions for the persons having high blood pressure.

A sphygmomanometer or blood pressure meter is a device used to measure blood pressure.

Epinephrine (adrenaline) and norepinephrine (noradrenaline) is a neurotransmitter which regulates the contraction and relaxation of the heart. The effect of adrenalin is known as the fight-or-flight response. It increases the heart beat.

Blood pressure is defined as the pressure applied by the blood on the walls of arteries and veins during circulation. The instrument used is called a sphygmomanometer, and two variables are measured:
1. Systolic pressure, which occurs during heart muscle contraction, averages around 120 and is expressed in millimeters of mercury (mm Hg).
2. Diastolic pressure, which occurs during relaxation of the heart muscle, averages around 80 mm Hg.

Blood pressure is the pressure exerted by the flowing blood on the elastic walls of arteries. Blood pressure is measured in two stages- systolic and diastolic. The instrument by which we can measure blood pressure is called sphygmomanometer. In humans, the blood pressure is measured in the brachial artery.

Blood pressure is the pressure applied on the arteries and veins during the circulation. The instrument used is called a sphygmomanometer and two variables are measured as follows
1. Systolic pressure, which occurs during heart muscle contraction which forces blood into arteries, averages around 120mmHg and is expressed in millimeters of mercury (mm Hg).
2. Diastolic pressure, which occurs during relaxation of the heart muscle, averages around 80 mm Hg.

Hypertension is the term for blood pressure that is higher than normal (120/80). In this measurement, 120 mm Hg (millimeters of mercury pressure) is the systolic, or pumping pressure and 80 mm Hg is the diastolic, or resting, pressure.

Normal resting blood pressure or arterial blood pressure for an adult human being is about 120/80 mm Hg. Blood pressure is summarized by two measurements, systolic and diastolic, which depend on whether the heart muscle is contracting (systole) or relaxed between beats (diastole).

A healthy blood pressure reading should be lower than 120/80 mm Hg. Normal blood pressure is less than 120 mm Hg systolic and 80 mm Hg diastolic, and may vary from 90/60mm Hg to 120/80mm Hg in a healthy young woman. A blood pressure of 140/90 mmHg or higher indicates high blood pressure.

Blood pressure is regulated by the amount of water and salts. It is regulated by hormones secreted by the adrenal gland. Aldosterone regulates a number of salts and water in the blood. The fluctuation in the blood pressure is measured by Sphygmomanometer. It was invented by Samuel Siegfried Karl Ritter von Basch in 1881. Hence, the correct answer is option A.

Systole is the period of contraction of the ventricles of the heart that occurs between the first and second heart sounds of the cardiac cycle (the sequence of events in a single heart beat). Systole causes the ejection of blood into the aorta and pulmonary trunk.

The blood flows under great pressure in the arteries and veins. Blood pressure may be defined as the pressure exerted by the blood on the arteries and veins. It is measured by sphygmomanometer.

Blood pressure is the pressure applied on the wall of the arteries and veins. The systolic phase applies greater pressure than the diastolic phase. Normal blood pressure of human being must be 120/80mmHg.

The diastolic blood pressure measures the pressure in the arteries between heartbeats (when the heart muscle is resting between beats and refilling with blood). A normal diastolic blood pressure is 80mm of Hg.

The systole is a phase when the chambers of the heart relax and the blood is filled in the respective chambers. The pressure exerted by blood against its walls of an artery during ventricular contraction is systolic pressure. It is estimated as 120mm Hg.

Pulse pressure is the difference between the systolic and diastolic pressure readings. It is measured in millimeters of mercury (mmHg). It represents the force that the heart generates each time it contracts. Systolic pressure in human is 120 mm Hg and Diastolic pressure in human is 80 mm Hg. Therefore difference between them is 40mm Hg. 

Systolic pressure is measured in the arteries when the heart contracts and is 120 mm of Hg in a normal condition.

A sphygmomanometer is an instrument, attached to an inflatable air bladder cuff and used with a stethoscope, for measuring blood pressure in an artery. Systolic pressure is identified with the first of the continuous korotkoff sounds. Diastolic pressure is identified at the moment the korotkoff sounds disappear. 

Hypertension is defined as an increase in the blood pressure in the arteries. It is a severe condition which may lead to heart strokes. Normal blood pressure at rest is within the range of 100-140 mm Hg systolic (top reading) and 60-90 mm Hg diastolic (bottom reading). 

A sphygmomanometer is an instrument attached to an inflatable air bladder cuff and used with a stethoscope, for measuring blood pressure in an artery. It is estimated with reference to mmHg.

The instrument used for measuring blood pressure is known as sphygmomanometer. The blood pressure is measured in mm of Hg (millimetres of mercury) and recorded with systolic number first followed by diastolic. In a normal adult, BP is 120/80 mm Hg.

• Systolic pressure is the pressure in blood vessels or the force of blood against the wall of arteries when the ventricles pump out blood into them. It is about 120 mm Hg.
• Diastolic pressure is the pressure or the force of blood against the wall of arteries when the heart is relaxing and getting refilled with blood. It is about 80 mm Hg.

• Blood pressure is the pressure which is exerted by blood against the wall of the arteries. 
  
• The average pressure produced in the ventricles when they contract and the blood is pumped into the aorta and the pulmonary artery is known as the systolic pressure, it is equal to the pressure exerted by a column of 120 mm of mercury. 
  
• The average pressure produced in the ventricles when they relax and are filled with blood is known as the diastolic pressure, it is about 80 mm of mercury. Hence the value of blood pressure in an adult is about 120/80.
  
• The blood pressure is measured by an instrument known as the sphygmomanometer.
  

The ejection of blood into the arteries causes the pressure within the arteries to rise, so the ventricular blood pressure is the highest in contracting arteries.

Adrenal medulla secrets adrenaline in response to stress and emergency condition. These hormones increase alertness, pupillary dilation, sweating etc. Both the hormones increase the heartbeat, the strength of heart contraction, blood pressure, rate of respiration.

Noradrenaline are rapidly secreted in response to the stress of any kind and during emergency situations and are called emergency hormones. In the rest of the  body, norepinephrine increases the heart rate and blood pressure.

When renal blood flow is reduced, the enzyme renin is secreted by the kidney cells. This promotes the conversion of angiotensinogen, produced by the liver, to angiotensin, which stimulates the production of aldosterone by the adrenal cortex. Aldosterone increases the reabsorption of sodium and water and the excretion of potassium by the kidneys. This raises the blood volume and the flow of blood through the kidneys, suppressing renin production and reducing aldosterone secretion.

As stated in the passage ANP is secreted by heart atrium in response to high blood pressure when the atrial wall is stretched.

As stated in the passage Renin-Angiotensin system increase blood pressure by causing retention of sodium and stimulation mineralocorticoid secretion. ANP reduces the blood pressure by excreting out sodium and excess water and vasodilation.

The atrial natriuretic hormone (ANP) is a cardiac hormone in which gene and receptors are widely present in the body. Its main function is to lower blood pressure and to control electrolyte homeostasis. So the correct option is 'Increase blood pressure'.

Exercise-Induced Pulmonary Haemorrhage (EIPH), commonly known as bleeding, is the most widely recognized of all disorders affecting racehorses. EIPH is characterized by bleeding from the lungs after strenuous exercise. Research studies have shown that horses experience unusually high blood pressures within the lungs during exercise. Deep within the lung, thousands of tiny air sac or alveoli interface with capillaries, forming the blood-gas barrier. This incredibly thin barrier readily allows oxygen to move from the lungs into the blood (and carbon dioxide to move in the opposite direction). This blood-gas barrier is not sufficiently strong in horses, to withstand high stress on the capillary wall, that exist during races or intense exercise. Due to which some lung capillaries get ruptured and release blood into the airways. The term "pulmonary capillary stress failure" is also used to describe this phenomenon. 

When the heart beats, it contracts and pushes blood through the arteries to the rest of the body. This force creates pressure on the arteries. This is called as systolic blood pressure. A normal systolic blood pressure is 120 mm hg. The diastolic blood pressure indicates the pressure in the arteries when the heart rests between beats. A normal diastolic blood pressure number is 80 mm hg.

High blood pressure is a non-infectious (non-communicable) condition. It is often caused by excessive weight and lack of exercise. 

Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. When blood vessels constrict, the flow of blood is restricted or decreased, thus increasing vascular resistance causing a reduction in blood flow. Thus, vasoconstriction usually results in an increase in systemic blood pressure.

Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels. It is usually measured at a person's upper arm. Blood pressure is usually expressed in terms of the systolic (maximum) pressure over diastolic (minimum) pressure and is measured in millimeters of mercury (mm Hg). It is one of the vital signs along with respiratory rate, heart rate, oxygen saturation, and body temperature. Normal resting blood pressure in an adult is approximately 120/80 mm Hg.

Systole refer to the contraction phase of the cardiac cycle of the heart between the first and second heart sounds of the cardiac cycle. Systole causes the contraction of the ventricles of the heart leading to ejection of blood into the aorta and pulmonary trunk.
Therefore, the correct answer is option D.

The arteries carry blood away from the heart, while veins return blood to the heart. With both, their structure is related to their function. Blood in the arteries is under high pressure generated by the heart. The arteries have thick outer walls and thick layers of muscle and elastic fibers. The blood in veins is under lower pressure than the blood in arteries. The veins have thin walls and thin layers of muscle and elastic fibers. Unlike arteries, veins have one-way valves in them to keep the blood moving in the correct direction.

The instrument used to find out the blood pressure is known as a sphygmomanometer. It is a device composed of an inflatable cuff which displays the pressure measured in mm Hg on the mechanical manometer. 

The sphygmomanometer is a device used to measure blood pressure. It consists of an inflatable cuff, a measuring unit and a mechanism for inflation which may be a manually operated bulb and a valve operated electrically.

Drowsiness after a heavy lunch is felt due to :

During systole, because of heart contraction blood is pumped into arteries. Blood pressure is highest as it leaves the heart through the aorta and gradually decreases as it enters smaller and smaller blood vessels (arteries, arterioles, and capillaries). While during atrial diastole, both atria are relaxing, dilating and filling. Blood pressure drops to the lowest level during this state.