There are many reasons kids' hair might fall out abnormally or excessively. Tinea capitis. The most common cause of hair loss in children is an infection known as tinea capitis. Tinea capitis is a type of ringworm that attacks the hair and causes scaly, ring-like lesions to form.
The right atrium pumps blood through the right atrioventricular (tricuspid) valve to the right ventricle. From the right ventricle, blood flows through the pulmonary valve to the lungs via the pulmonary arteries (deoxygenated blood).In the lungs the blood becomes more red in color as it is oxygenated.Blood returns to the heart via the pulmonary veins (oxygenated blood) to the left atrium.The left atrium pumps blood through the left atrioventricular (bicuspid or mitral) valve to the left ventricle.n the lungs the blood becomes more red in color as it is oxygenated. Blood returns to the heart via the pulmonary veins (oxygenated blood) to the left atrium. The left atrium pumps blood through the left atrioventricular (bicuspid or mitral) valve to the left ventricle.
The oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. This blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. From the left ventricle, the blood passes through the aortic valve to the aorta.