Birth defect in the context of "Gills"

A gill (/ɡɪl/ ) is a specialized respiratory organ that many aquatic animals use for aquatic gas exchange, i.e. to extract dissolved oxygen from water and to excrete carbon dioxide. Branchia (pl.: branchiae, from Ancient Greek βράγχια) is the zoologists' academic name for gills.

The gills of some semi-aquatic clades (e.g. crabs, terrestrial hermit crabs and amphibious fishes), have also adapted to allow air respiration (breathing) on land provided the gills are kept moist. In some terrestrial chelicerates species (tetrapulmonates such as spiders and scorpions), their ancestral gills have evolved into fully air-breathing book lungs. In some planktivorous bony fish species (e.g. silver and bighead carps), the gills are also used as a filter feeding organ via comb-like projections called gill rakers.

Disability is the experience of any condition that makes it more difficult for a person to do certain activities or have equitable access within a given society. Disabilities may be cognitive, developmental, intellectual, mental, physical, sensory, or a combination of multiple factors. Disabilities can be present from birth or can be acquired during a person's lifetime. Historically, disabilities have only been recognized based on a narrow set of criteria—however, disabilities are not binary and can be present in unique characteristics depending on the individual. A disability may be readily visible, or invisible in nature.

The United Nations Convention on the Rights of Persons with Disabilities defines disability as including:

Infant mortality is the death of an infant before the infant's first birthday. The occurrence of infant mortality in a population can be described by the infant mortality rate (IMR), which is the number of deaths of infants under one year of age per 1,000 live births. Similarly, the child mortality rate, also known as the under-five mortality rate, compares the death rate of children up to the age of five.

In 2013, the leading cause of infant mortality in the United States was birth defects. Other leading causes of infant mortality include birth asphyxia, pneumonia, neonatal infection, diarrhea, malaria, measles, malnutrition, term birth complications such as abnormal presentation of the fetus, umbilical cord prolapse, or prolonged labor. One of the most common preventable causes of infant mortality is smoking during pregnancy. Lack of prenatal care, alcohol consumption during pregnancy, and drug use also cause complications that may result in infant mortality. Many situational factors contribute to the infant mortality rate, such as the pregnant woman's level of education, environmental conditions, political infrastructure, and level of medical support. Improving sanitation, access to clean drinking water, immunization against infectious diseases, and other public health measures can help reduce rates of infant mortality.

Brain injury, also known as brain damage or neurotrauma, is the destruction or degeneration of brain cells. It may result from external trauma, such as accidents or falls, or from internal factors, such as strokes, infections, or metabolic disorders.

Traumatic brain injury (TBI), the most common type of brain injury, is typically caused by external physical trauma to the head. Acquired brain injuries occur after birth, in contrast to congenital brain injuries that patients are born with.

Disfigurement is the state of having one's appearance deeply and persistently harmed medically, such as from a disease, birth defect, or wound. General societal attitudes towards disfigurement have varied greatly across cultures and over time, with cultures possessing strong social stigma against it often causing psychological distress to disfigured individuals. Alternatively, many societies have regarded some forms of disfigurement in a medical, scientific context where someone having ill will against the disfigured is viewed as anathema. In various religious and spiritual contexts, disfigurement has been variously described as being a punishment from the divine for sin (such as Yahweh's defacement of Cain for Abel's murder in Judaism), as being (such as Paul of the New Testament's arguments about Christ's sufferings) caused by supernatural forces of hate and evil against the good and just, which will be later atoned for, or as being without explanation per se with people just having to endure.

The topic has been frequently commented on and referred to in a great many forms of fictional media as well. Villainous examples include the iconic fiend The Joker from various DC Comics and the mysterious figure with a "red right hand" from the song of the same name by the band Nick Cave and the Bad Seeds. Heroic examples include Daredevil, a crime-fighter who was rendered blind (from Marvel Comics), and the compassionate character Edward Scissorhands from the film of the same name. Antiheroic examples include Deadpool, a mercenary whose healing factor gives his skin a scarred appearance, and The Punisher, who has facial disfigurement, also from Marvel Comics.

Hemiparesis, also called unilateral paresis, is the weakness of one entire side of the body (hemi- meaning 'half'). Hemiplegia, in its most severe form, is the complete paralysis of one entire side of the body. Either hemiparesis or hemiplegia can result from a variety of medical causes, including congenital conditions, blunt trauma, tumors, traumatic brain injury, and stroke.