Oxyhemoglobin

Oxygenated hemoglobin, a protein present in red blood cells or erythrocytes.  The oxygen-carrying pigment of arterial red blood cells serves to convey oxygen to tissues.  It is composed from hemoglobin when exposed to the alveolar gas in the lungs.  Functional magnetic resonance imaging (fMRI) and other brain imaging techniques function on the basis that oxyhemoglobin …

Oxytocin

Colloquially referred to as the ‘love hormone’, its a mammalian pituitary hormone and neurotransmitter that stimulates smooth muscle contraction (e.g., of the uterus during labor) and sensitizes nerves.  The posterior pituitary gland, in fact, holds and secretes oxytocin produced by the hypothalamus.  Dopamine (the ‘pleasure’ or ‘reward’ hormone) stimulates the production of oxytocin.  Animal studies …

Own-sex schema

Organized sets of beliefs about the characteristics associated with one’s own sex.  According to gender schema theory, originally formulated by Sandra L. Bem in 1981, there are two levels of schemata that concern such beliefs.  One is the superordinate schema that is the repository for stereotypes that children and adults have about the defining characteristics …

Oversampling

Increasing the proportionate representation of a given group in a study in order to increase the statistical power of tests comparing associations among variables in that group with associations in other study groups.  It is a procedure of stratified sampling involving the selection of a disproportionate number of participants from a particular group or stratum. …

Otoliths

The otoliths consist of two organs in the inner ear: saccule and utricle.  Both consist of stones (small calcium carbonate particles in a gelatinous membrane) resting on hairs (stereocilia).  Motions of the head result in the stones exerting a shearing force on the hairs, which is detected by the hair cells.  The impulse is sent …

Ossification

Process of bone formation involving calcification of cartilage or connective tissue.  Cartilage is a dense bone connective tissue, with many properties similar to bone (but it can‚eat be remodelled), and both rely on the secretion of a rigid extracellular matrix.  It develops when mesenchyme cells on the proximal, central core of the limb bud transform into …