Cone of light Cone of light The cone of light, or light reflex, is a visible phenomenon which occurs upon examination of the tympanic membrane with an otoscope. Shining light on the tympanic membrane causes a cone-shaped reflection of light to appear in the anterior inferior quadrant. This corresponds to the 4 o'clock to 5 o'clock position in the right eardrum and the 7 o'clock to 8 o'clock position in the left eardrum. The apex of the cone is at the most depressed part of the tympanic membrane, known as the umbo. The absence of a cone of light does not necessarily signify
Plasma membrane Ca2+ ATPase to involve the lymph nodes, and are more common among young women, which could help explain their worse prognosis compared with postmenopausal women. PMCAs were first discovered in the 1960s in the membranes of red blood cells. The presence of an ATPase was discovered in the membranes in 1961, and then in 1966 it was discovered that these ATPases pump Ca out of the cytosol. PMCA was first purified from red blood cell membranes in 1979. Plasma membrane Ca2+ ATPase The plasma membrane Ca ATPase (PMCA) is a transport protein in the plasma membrane of cells and functions to remove