CARTA Glossary

Displaying 201 - 300 of 523 defined words
Word Definition Related Vocabulary
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.

Great Apes

A taxonomic family that was once incorrectly used to denote chimpanzees, bonobos, gorillas and orangutans, but not humans.

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).

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

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

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 (HAR1 showing the largest degree of human-chimpanzee differences).

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).

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.

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.

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.”

Interbirth Interval

The period of time between successive births by an individual female.

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.

Lactobacillus iners

A common genus of beneficial Lactobacillus bacteria that normally inhabits the lower reproductive system and vagina of healthy women.

Late Bloomers

Individuals from high-risk backgrounds who begin to manifest resilience later in adolescence or adulthood following a period of maladjustment or problems.

Levallois Technique (prepared core)

A method of creating stone tools by first striking flakes off the stone, or core, along the edges to create the prepared core and then striking the prepared core in such a way that the intended tool is flaked off with all of its edges pre-sharpened.

Limited Bedding and Nesting

A paradigm used in the laboratory to model scarcity of resources. Mothers (rats/mice) are not given enough nesting materials to build a nest for their infants and neglect/maltreatment occurs as a result.

Linkage Disequilibrium

Non-random inheritance of alleles at different loci (due to low recombination).

Lipid

One of the four classes of major biomolecules. A fatty or waxy organic compound involved in important cellular activities like storing energy, as a component of the cell membrane, and signaling within and between other cells.

Locus (pl. Loci)

A unique physical position on a chromosome.

Lomekwian Technology

The oldest known stone tools consisting of 150 artifacts found in Lomekwi, Kenya, close to Lake Turkana. ~3.3 mya.

Lower Paleolithic

The first subdivision of the Paleolithic, or Stone Age. ~3.4 mya- 300 ky.

Macronutrient

A substance required in relatively large amounts by living organisms: Fats, proteins, carbohydrates in an animal diet or chemical elements such as potassium, magnesium, calcium as required by plants.

Maintenance and Defense

An organism’s way of maintaining its body and physiological homeostasis while also defending against parasites, pathogens, and internal crises (e.g. cancer).

Maladaptation

A genotypic or phenotypic trait that is (or has become) more harmful than helpful in determining survival and reproductive success (in contrast to an adaptation, which is more helpful than harmful).

Malaria

An infectious disease that affects humans and other animals and caused by single-celled organisms belonging to genus Plasmodium and transmitted by mosquitos (commonly female Anopheles mosquitos). Initial symptoms are flu-
like and may include headache, fever, shivering, joint pain, vomiting, anemia, jaundice, hemoglobin in the urine, retinal damage, and convulsions. The classic symptom of malaria is a cyclical occurrence of sudden coldness and shivering and then fever and sweating. The disease is widespread in tropical and subtropical regions of the equator. In 2018, there were 228 million cases of malaria worldwide resulting in an estimated 405,000 deaths. The high levels of mortality caused by malaria has repeatedly placed selective pressure on the human genome, resulting in several genetic factors (including Sickle Cell Trait) that mediate its effect to some degree.

Marrow

The soft fatty substance in the cavities of bones that produces red and white blood cells and platelets.

Maternal Separation

An experimental paradigm in which the experimenter separates a mother rat or mouse from her offspring for some period of time (minutes to hours) to study the effects of maternal deprivation on offspring development.

Mechanistic Target of Rapamycin (mTOR)

A protein kinase, which in humans is encoded by the MTOR gene.

Medial Preoptic Area (MPOA)

A region of the brain located in the anterior part of the hypothalamus that critically regulates care giving behavior.

Medium Spiny Neurons

A special type of GABAergic inhibitory cell representing 95% of neurons within the human striatum, a basal ganglia structure.

Memory

The faculty by which the mind stores and remembers information.

Meningococcus (Neisseria meningitidis)

A bacterium that can cause meningitis and meningococcemia, a life-threatening infection in the bloodstream (sepsis).

Microbiome

The totality of all organisms (microbes) that live on and in the body.

Microlithic (Mode 5)

A stone tool type consisting of small blades or points, called microliths, that were typically used in composite tools, such as an arrow point fastened to a haft. ~35 - 3 kya.

Micronutrients

A chemical element or substance required in trace amounts for the normal growth and development of living organisms that the organism cannot synthesize itself. 

Middle East Respiratory Syndrome (MERS

A contagious and sometimes fatal viral respiratory sickness that can produce severe symptoms such as fever, cough, shortness of breath and in some cases death. The MERS virus originated in bats and was first reported affecting other species, camels and humans, in Saudi Arabia in 2012. Since then, it has been identified in many other countries, including the United States.
 

Middle Paleolithic

The second subdivision of the Paleolithic, or Stone Age and consist of use of prepared cores (Levallois Technique) and hafted tools and weapons. ~300 kya -30 kya.

Middle Pleistocene

A period of geological time (781-126,000 years ago). An important time for the diversification of hominins, including the emergence of Neanderthals and Homo sapiens.

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