Mindblown: a blog about philosophy.

Bilirubin Definition Bilirubin is a molecule formed from the breakdown of red blood cells, and other cells with porphyrins. Red blood cells carry special molecules, called hemes (a type of porphyrin), which hosts an iron atom. This arrangement allows the red blood cell to carry oxygen. When blood cells break down, they release the heme into the blood,…

Definition Bile salts are found in bile, a secretion produced by liver cells to aid digestion. Although bile is 95% water, bile salts are its most prominent organic solutes and play a major role in fat emulsification. Human bile contains at least twelve bile salts. Only two of these are primary or synthesized in the…

Bilateral Symmetry Definition Bilateral symmetry refers to organisms with body shapes that are mirror images along a midline called the sagittal plane. The internal organs, however, are not necessarily distributed symmetrically. The vast majority of animals display bilateral symmetry; also known as plane symmetry, this is a trait that applies to 99% of all animals, in the…

Beta Oxidation Definition Beta oxidation is a metabolic process involving multiple steps by which fatty acid molecules are broken down to produce energy. More specifically, beta oxidation consists in breaking down long fatty acids that have been converted to acyl-CoA chains into progressively smaller fatty acyl-CoA chains. This reaction releases acetyl-CoA, FADH2 and NADH, the…

Definition of Benthos The benthos is comprised of all the organisms that live at the bottom of a body of standing or running water. The layer that the benthos occupy is called the benthic zone, which is the lowest layer of a lake, sea, stream, or river. This zone, of course, ranges from the shallow depths…

Base Pair Definition Base pairs refer to the sets of hydrogen-linked nucleobases that make up nucleic acids DNA and RNA. They were first described by Dr. Francis Crick and Dr. James Watson who are best known for discovering the helical, “twist around,” structure of DNA (1953). At this time, DNA was also identified as the…

Barr Body Definition The Barr body, also sometimes called the sex chromatin, is the inactive X chromosome in female somatic cells. Human females have two X chromosomes, while males have one X and one Y. In all of the female somatic cells, which don’t take part in sexual reproduction, one of the X chromosomes is active,…

Bacterial Conjugation Definition Bacterial conjugation is a way by which a bacterial cell transfers genetic material to another bacterial cell. The genetic material that is transferred through bacterial conjugation is a small plasmid, known as F-plasmid (F for fertility factor), that carries genetic information different from that which is already present in the chromosomes of…

Bacteria Definition Bacteria are single-celled microorganisms with prokaryotic cells, which are single cells that do not have organelles or a true nucleus and are less complex than eukaryotic cells. Bacteria with a capital B refers to the domain Bacteria, one of the three domains of life. The other two domains of life are Archaea, members…