Search results
Results from the WOW.Com Content Network
The heart is a muscular organ situated in the mediastinum.It consists of four chambers, four valves, two main arteries (the coronary arteries), and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left ...
The identification of the heart as the seat of emotions in particular is due to the Roman physician Galen, who also located the seat of the passions in the liver, and the seat of reason in the brain. [119] The heart also played a role in the Aztec system of belief. The most common form of human sacrifice practiced by the Aztecs was heart ...
Fourth ventricle location shown in red (E), pons (B); the floor of the ventricle is to the right, the roof to the left. The fourth ventricle has a roof at its upper (posterior) surface and a floor at its lower (anterior) surface, and side walls formed by the cerebellar peduncles (nerve bundles joining the structure on the posterior side of the ventricle to the structures on the anterior side).
The human arterial system originates from the aortic arches and from the dorsal aortae starting from week 4 of embryonic life. The first and second aortic arches regress and form only the maxillary arteries and stapedial arteries respectively. The arterial system itself arises from aortic arches 3, 4 and 6 (aortic arch 5 completely regresses).
The heart works by pumping blood around the body allowing oxygen, nutrients, waste, hormones and white blood cells to be transported. Diagram of the human heart. The heart is composed of two atria and two ventricles. The primary purpose of the atria is to allow uninterrupted venous blood flow to the heart during ventricular systole.
Heart development, also known as cardiogenesis, refers to the prenatal development of the heart. This begins with the formation of two endocardial tubes which merge to form the tubular heart, also called the primitive heart tube. The heart is the first functional organ in vertebrate embryos.
The human brain is the central organ of the nervous system, and with the spinal cord, comprises the central nervous system. It consists of the cerebrum, the brainstem and the cerebellum. The brain controls most of the activities of the body, processing, integrating, and coordinating the information it receives from the sensory nervous system ...
The cardiovascular centre affects changes to the heart rate by sending a nerve impulse to the cardiac pacemaker via two sets of nerves: sympathetic fibres, part of the autonomic nervous system, to make heart rate faster. the vagus nerve, part of the parasympathetic branch of the autonomic nervous system, to lower heart rate.