Mindblown: a blog about philosophy.

The blood cell that carries oxygen. Red cells contain hemoglobin and it is the hemoglobin which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being a transport molecule, is a pigment. It gives the cell its red color (and name). The mature red blood cell (RBC) is a non-nucleated biconcave disk. Thanks to this unusual…

Appearing or occurring again. For example, a recurrent fever is a fever that has returned after an intermission, a recrudescent fever.

The return of a sign, symptom, or disease after a remission. The reappearance of cancer cells at the same site or in another location is a form of recurrence.

To occur again; to return. For example, a symptom, sign, or disease can recur.

The last 6 to 8 inches of the large intestine. The rectum stores solid waste until it leaves the body through the anus.

An extension of the peritoneal cavity between the rectum and back wall of the uterus. The term “cul-de-sac,” aside from being any “blind pouch or cavity that is closed at one end,” is used specifically to refer to the rectouterine pouch. From that fact comes: In French, “cul-de-sac” literally is “bottom of (a)sack.” As early as the 13th century, a cul-de-sac was a…

Bulging of the front wall of the rectum into the vagina. Rectocele is due to weakening of the pelvic support structures and thinning of the rectovaginal septum (the tissues separating the rectum from the vagina). Also called a proctocele. Risk factors for a rectocele include a history of multiple, difficult or prolonged deliveries, forceps or other assisted methods of delivery, perineal tears, an episiotomy into…

Blood passed rectally. Blood in the stool can be bright red or maroon in color. Larger amounts of blood that remain in the intestine long enough can turn the stool black. Blood in the stool also may be invisible to the naked eye (occult). The causes of blood in the stool range from harmless, annoying conditions of…

Having to do with the rectum, the last 6 to 8 inches of the large intestine that serves to store solid waste until it leaves the body through the anus. The word “rectal” comes from the Latin “rectus” meaning “straight” (which the human rectum is not).

The RDA, the estimated amount of a nutrient (or calories) per day considered necessary for the maintenance of good health by the Food and Nutrition Board of the National Research Council/ National Academy of Sciences. The RDA is updated periodically to reflect new knowledge. It is popularly called the Recommended Daily Allowance.