CARTA Glossary

Displaying 201 - 300 of 577 defined words
Word Definition Related Vocabulary
Gene Regulation

Alterations of gene expression/activity.

Gene-Culture Co-Evolution Theory

A branch of theoretical population genetics that models the transmission of genes and cultural traits from one generation to the next, exploring how they interact. Also known as “biocultural evolution” or “biological enculturation” (feedback between culture and biology).

Genetic Adaptation

A biological characteristic with a heritable basis that improves reproduction and/or survival and results from evolution by natural selection.

Genetic Drift

Change in allele frequencies, including fixation and loss, by chance.

Genetics

The study of genes and their inheritance.

Genius

A person who is exceptionally intelligent or creative, either generally or in some particular respect.

Genome

All DNA in a cell. Also refers to the DNA sequence that typifies an individual or species.

Genome Wide Association Study (GWAS)

An approach for “gene mapping” in which hundreds of thousands of SNPs are tested statistically for genetic associations with a phenotype.

Genomic Imprinting

Modification of the genome at the level of DNA (e.g. methylation) or its packaging into chromatin (histone tail modification via phosphorylation, acetylation, ubiquitination or glycosylation).

Genomics

The study of genome structure/function.

Genotype

The two alleles at one or more diploid loci.

Genotyping

Characterizing genetic variants at one or more loci.

Genus

A taxonomic rank used in biological classification of living and fossil organisms to group closely related species. In binomial nomenclature, the genus name plus species name forms the binomial species name (e.g. Homo sapiens).

Germinal Zone A region where cell division and proliferation occurs during vertebrate central nervous system development consisting of 2 layers lining the ventricles (ventricular zone and subventricular zone).
Glia (aka Neuroglia)

Non-neuronal cells in the central nervous system and the peripheral nervous system that do not produce electrical impulses. Their function is to ensure homeostasis, form myelin, and provide support and protection for neurons.

Glycans

One of the four classes of major biomolecules. Glycans consist of varying numbers of sugars (monosaccharides) attached to proteins or lipids or secreted as free glycans. Glycans are essential biomolecules whose functions can be divided into three broad categories: structural and modulatory properties (including nutrient storage and sequestration), specific recognition by other molecules, and molecular mimicry of host glycans.

Glycolipids

A type of a lipid (fat) with an attached glycan that functions to maintain the stability of the cell membrane and to facilitate cellular recognition. Glycolipids are crucial in immune response and tissue formation.

Glycoprotein

A class of proteins with covalently attached glycans. Glycoproteins play a part in important cellular functions like embryonic development, cell-to-cell recognition, cell adhesion, and immune functions.

Gram-Negative and Gram-Positive Staining

A characterization of bacteria based on how they differentially react with a chemical stain (crystal violet) based on their cell wall constituents.

Grandmother Hypothesis

An explanation of the post- menopausal life stage of human females whereby the existence of grandmothers serves as a biological and social adaptive advantage for humans. Post-reproductive life stages are non-existent among non-human primates, so it is hypothesized that humans evolved to have grandmothers and grandmothering to have individuals who are free to invest their energy into the offspring of their children. This off-loads the reproductive cost of parenting through social kin-networking, and off-set the resource cost of brain- building as parents are freed to provision resources. Increased resource procurement may reduce the inter-birth interval by allowing for earlier weening, which in turn increases offspring production potential, passes down generational knowledge, and increase social networks. In doing so, the grandmother ensures the survival of her genes in subsequent generations. The extended post-reproduction lifestage of grandmothers likely had the added output of producing grandfathers, who also provide benefits to the extended family, as well as their own extended reproductive timeline that competes with subsequent generations.

Gray Matter (Brain)

A major component of the central nervous system that includes regions of the brain involved in muscle control, sensory perception such as seeing and hearing, memory, emotions, speech, decision making, and self-control. Gray matter development peaks the third decade in humans.

Great Apes

A taxonomic family denoting the extant chimpanzees, bonobos, gorillas and orangutans.

Guillain–Barré Syndrome (GBS)

A rapid-onset muscle weakness caused by an autoimmune response in which the body’s immune system mistakenly attacks and damages the peripheral nervous system. Initial symptoms typically begin in the feet and hands with changes in sensation, pain, and muscle weakness, which then spreads to the arms and upper body of both sides. Sometimes this immune dysfunction is triggered by an infection or, less commonly by surgery, and rarely by vaccination.

Gyrification

The process of forming the characteristic folds of the cerebral cortex.  The peak of such a fold is called a gyrus (plural: gyri), and its trough is called a sulcus (plural: sulci).

Gyrus (Brain)

A ridge on the cerebral cortex that, along with surrounding sulci (furrows) creates the folded appearance of the brain in humans and other mammals.

Hadza (Hadzabe)

An indigenous ethnic group of traditionally nomadic hunter-gatherers from the central Rift Valley and Serengeti Plateau of Tanzania. Tourism, encroachment by pastoralists, and land rights disputes critically threaten their way of life.

Handaxe

A prehistoric stone tool with two faces and is usually made from flint, basalt, sandstone, quartzite, or chert.

Haplogroup

A set of similar haplotypes that share a common ancestor.

Haploid

One set of unpaired chromosomes.

Haplotype

A set of alleles along neighboring positions on a chromosome that are inherited together.

Health Disparity

Differences in the burden of disease, injury, violence, and health care as experienced by socially disadvantaged populations.

Hemideletion

One of two paired chromosomes is affected by a deletion. The other chromosome is intact. 

Hemoglobin

A protein complex within red blood cells (RBCs) that binds to oxygen molecules in the lungs for delivery to tissues throughout the body. The same complex also binds carbon dioxide (CO2) and carries it back to the lungs.

Hemoglobin S

The abnormal hemoglobin protein in red blood cells (RBCs) that causes RBCs to assume a sickle, or crescent shape.

Hemoglobin Subunit Beta Gene (HBB)

A gene that provides instructions for making beta-globin, a protein component of hemoglobin. Sickle Cell Anemia is a disorder caused by a mutation in the HBB gene.

Herd Immunity

Sometimes also called “herd protection” or “indirect immunity,” this is when most of a population is immune to a specific contagious disease, which slows its spread to others that are not immune. However, because the level needed to reach this kind of immunity is so high (about 80-90% of the population), it invariably means that a lot of individuals must be infected (and often can die) before herd immunity can be achieved.

Heritability

A statistic used in the fields of breeding and genetics that estimates the degree of variation in a phenotypic trait in a population that is due to genetic variation between individuals in that population.

Heterochromatin

Tightly wrapped and inactive chromatin.

Heterozygotes

Have two different alleles at a locus.

Hippocampus (Brain)

A part of the limbic system that plays important roles in the consolidation of information from short-term memory to long-term memory, and in spatial memory that enables navigation. A major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. It is named after its resemblance to the shape of a sea horse.

Histone Deacetylase Inhibitor (HDACi)

A drug that inhibits histone deacetylases or molecules involved in modifying histone proteins. Histone deacetylases typically function to reduce chromatin accessibility and gene expression. Therefore, administration of this drug allows for higher levels of gene expression.

Histone Modification

A covalent post-translational modification (PTM) to histone proteins which includes methylation, phosphorylation, acetylation, ubiquitylation, and sumoylation. The PTMs made to histones can impact gene expression by altering chromatin structure or recruiting histone modifiers. 

Histones

Chief protein components of chromatin and can be chemically modified as part of epigenetics.

Holocene

The current geological epoch, from about 11.7 kya to the present.

Homeostasis

A relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes.

Hominid

A classification comprising all living and extinct “Great Apes” and humans.

Hominin

A classification of species comprising humans and our extinct relatives following the split with the common ancestor with chimpanzees.

Homo

The genus that comprises the species Homo sapiens, as well as several extinct species classified as ancestral to, or closely related to, humans.

Homo erectus

An extinct hominin species with fossil evidence from at least 1.9 million years to 70 thousand years ago and found from Africa to Indonesia. May have been the first hominin to leave Africa. H. erectus DNA may be retrievable from other species due to archaic admixture.

Homo habilis

An extinct archaic species of the genus Homo dating to ~2.1 to 1.5 mya. H. habilis means “handy man” and was named so because of its association with stone tools.  H. habilis has intermediate morphology between Australopithecus and Homo erectus. There is ongoing debate if H. habilis should be moved to the Australopithecus genus.  Initial discovery was made by Mary and Louis Leakey at Olduvai Gorge in Tanzania between 1962 and 1964.

Homo naledi

An extinct hominin species whose fossil evidence dates to 335-236 kya. An assemblage of 15 H. naledi skeletons were first found in the Dinaledi Chamber of the Rising Star cave system in 2013 (since then, a second chamber has been found with H. naledi skeletons). The fossils possess a mix of “archaic” traits similar to genus Australopithecus (e.g. cranial and pelvic morphology) and “modern” traits characteristic of genus Homo (e.g. hand morphology). H. naledi lived contemporaneously with anatomically modern humans, Neanderthals, and Denisovans but is not likely a direct ancestors of humans living today.

Homo sapiens

The hominin species comprising all living humans. Meaning “wise man” in Latin, the name was introduced by Carl Linnaeus in 1758. The earliest fossil evidence of Homo sapiens appears in Africa around 300 kya (see Jebel Irhoud Hominins).

Homology

Similarity in DNA or phenotype because of shared evolutionary history from a common ancestor.

Homoplasy

Similarity in DNA sequence or phenotype that has evolved independently.

Homozygotes

Have two identical alleles at a locus

Host

A living organism on or in which a parasite, pathogen, commensal or symbiont lives (see Parasitism).

Howiesons Poort

A lithic technology cultural period in the Middle Stone Age in Africa named after the Howieson’s Poort Shelter archeological site near Grahamstown, South Africa. Dates range from ~65.8 kya to 59.5 kya. Examples include composite weapons hafted with ochre and gum compound glue and microlith blades, bone arrows, and needles.

Human Accelerated Regions (HARs)

A set of 49 segments of the human genome that are conserved throughout vertebrate evolution but are strikingly different in humans. They are named according to their degree of difference between humans and chimpanzees. Some of these highly mutated areas may contribute to human-specific traits while others may represent “loss of function” mutations, possibly due to the action of biased gene conversion rather than adaptive evolution.

Hunter-Gatherer

A human living in a society in which most or all food is obtained by foraging (collecting wild plants and pursuing wild animals), in contrast to agricultural societies, which rely mainly on domesticated species.

Hybridization

Breeding among recognized species.

Hygiene Hypothesis

A lack of early childhood exposure to infectious agents, symbiotic microorganisms and parasites believed to increase susceptibility to allergies and autoimmune diseases.

Hypoxia

Less than the normal amount of oxygen reaching the tissues; also, low partial pressure of oxygen at high elevations (hypobaric hypoxia).

Icon

A sign that shares perceived physical properties with the thing it refers to (its “referent”) (Kluender, 2020).

Idiosyncrasy

A mode of behavior or way of thought peculiar to an individual.

Immediate Return Hunter-Gatherers

Those who do not store food, but consume it within a day or two of obtaining it. This means there is no opportunity to accumulate surplus.

Immune Cells

Cells that are part of the immune system. Most develop from stem cells in the bone marrow and become different types of white blood cells (the microglia of the brain originate in the yolk sack during embryonic development). Immune cells are broadly classified into innate and adaptive immune cells. Innate immune cells include neutrophils, basophils, mast cells, monocytes and eosinophils, dendritic cells, and macrophages. Adaptive immune cells include B-cells and T-cells. T-Cells and Natural Killer T-cells mediate important dialogues between innate (rapid) and adaptive (slower) immune responses. B-cells and T-cells can form long- term immunological memory.

Immune System

The biological defense system of an organism that protects against disease.

Immunity

The capability of multicellular organisms to resist harmful microorganisms from entering it and compromising its biological systems. The balanced state of adequate biological defenses to fight infection, disease, or other unwanted biological invasion, while having adequate tolerance to avoid allergy, and autoimmune diseases. It critically relies on recognition of both self and non-self.

Immunoglobulin

A class of glycoproteins present in the serum and on cells of the immune system. (see Antibody)

Immunology

The branch of biology and biomedicine concerned with the study of immune systems.

IncRNA

Long non-coding microRNA

Indels

Insertions or deletions of DNA sequence.

Index

A sign that depends for its reference on the physical presence of the thing that it refers (its “referent”) to at some point in space and time (e.g. smoke, a weather vane, a bullet hole, your index finger) (Kluender, 2020).

Induced Pluripotent Stem Cells (iPSC)

Somatic (body) cells that are artificially reprogrammed to an embryonic-like stem cell state and differentiated into other types of cells.

Infection

The invasion of an organism’s organs or tissues by pathogens, their multiplication, and the reaction of the host tissues to the pathogens.

Infectious (Disease)

The capability of producing infection or spreading disease to others. Synonymous with communicable and transmissible.

Inferior Frontal Gyrus (Brain)

The lowest positioned gyrus of the frontal gyri, of the frontal lobe, and is part of the prefrontal cortex. It is located in Broca’s area, which is involved in language processing and speech production.

Inferior Temporal Cortex (Brain)

The cerebral cortex on the inferior convexity of the temporal lobe in primates, including humans and is It is crucial for visual object recognition.

Inflammation

An often-painful localized redness, swelling, and heat that is the body’s response to an injury or infection. While uncomfortable, it indicates that your body is working hard to repair itself or to defend against infection.

Influenza

Often referred to as “flu,” this is a highly contagious viral respiratory illness. Symptoms include fever, severe body aches, and catarrh. Because it is so contagious, influenza often produces epidemics. There are several influenza viruses that affect humans (A, B, C).

Intentionality

The power of minds to be about, to represent, or to stand for, things, properties and states of affairs. Refers to the ability of the mind to form representations and should not be confused with intention. Beliefs about others’ beliefs display what is sometimes known as “higher-order intentionality.”

Inter-birth-interval

The space between births.

Intracellular Signaling Cascade

The series of sequential events that transmit signals received at the surface of a neuron to internal regulatory molecules, which are then modified by the signal. These pathways allow external signals from the environment to regulate gene expression.

Intrauterine Life

The interval of life between conception and birth.

Introgression

Transfer of alleles between species.

Introns

Sequences between eons, don't encode proteins

Intuition

A thing that one knows or considers likely from instinctive feeling rather than conscious reasoning.

Isotope

Each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.

Isotopic Signature

The ratio of non-radiogenic “stable isotopes,” stable radiogenic isotopes, or unstable radioactive isotopes of particular elements in an investigated material.

Japanese Encephalitis

An infection of the central nervous system caused by the Japanese Encephalitis Virus. Most infections are benign but occasionally can cause inflammation of the brain (encephalitis), headaches, vomiting, fever, confusion and seizures.

Japanese Encephalitis Virus (JEV)

A RNA virus of the genus Flavivirus that causes Japanese Encephalitis and is generally spread by mosquitoes, such as Aedes mosquitos. JEV is prevalent in much of Asia and the Western Pacific. Pigs and wild birds serve as a reservoir for the virus.

Jaundice

A yellowing of the eyes and skin due to rapid breakdown of red blood cells (RBCs) and release of degraded hemoglobin.

Jebel Irhoud Hominins

The oldest known “early” human fossils discovered, dating to roughly 300 kya from an archaeological site in Morocco. The location of this discovery suggests a “pan-African” origin of humans, with a dispersed interbreeding population, likely aided by climactic factors.

John Ssebunya of Uganda

In 1989, at age 4-5, he witnessed his father murder his mother and subsequently fled into the Ugandan jungle. He was accepted as a peripheral member of a group of vervet monkeys who cared for and nourished him for a period of two years. He was found and captured in 1991.

Karyotype

Chromosome number in the cell nucleus.

Klasies-River

A river and cave system in the Tsitsikamma coast, Humansdorp district, Eastern Cape Province, South Africa. Evidence for middle stone age-associated human habitation has been found in the nearby cave system dating to ~125 kya.

Konso-Gardula

A palaeoanthropological area in the southern Main Ethiopian Rift that was discovered 1991 The Konso-Gardula sediments span ~ 1.9 mya to 1.3 mya. Early Homo fossils and Acheulean stone tools have been found here. 

KYA

Thousand years ago.

Lactobacillus

A genus of Gram-positive, rod-shaped bacteria that convert sugars to lactic acid. In humans, they are a significant component of the microbiome and can survive in the harsh pH conditions of the digestive and genital systems. Lactobacillus species are normally a major part of the vaginal microbiota. While receiving nutrients from their human host, Lactobacilli protect the host against certain pathogens, even helping to treat diarrhea, vaginal infections, and skin disorders such as eczema. Lactobacillus is the most common probiotic, perhaps most notable for its use in yogurt.

Lactobacillus crispatus

A common genus of beneficial Lactobacillus bacteria that produces hydrogen peroxide (H202) and is found in the vagina and gastrointestinal system.

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