Studied by 7 people
3' poly-A tail
a chain of adenine nucleotides added to the 3' end of pre-mRNA during RNA processing
5' methyl-G cap
a molecule added to the 5' end of pre-mRNA during RNA processing
absolute age
an estimate of the age (in years) of a fossil or rock
absolute dating
a dating technique used to determine the absolute age of a fossil by measuring the relative amounts of radioisotopes to their products. Also known as radiometric dating
accurate
how close a measurement is to the true value
acetyl-CoA
the product of the link reaction where pyruvate is conjugated to coenzyme A, creating the primary input into the Krebs cycle
activation energy
the energy required to initiate a reaction
activator protein
a protein coded for by a regulatory gene that increases gene expression
active immunity
protection against a disease created by antibodies and memory cells formed by a person's own adaptive immune system
active site
the part of an enzyme where the substrate binds
active transport
the movement of molecules across a semipermeable membrane requiring an energy input
adaptive potential
the ability for a population to adjust to new environmental selection pressures
adaptive radiation
the rapid divergent evolution of a species, thereby producing a wide array of species/forms
ADP
adenosine diphosphate, the unloaded form of ATP
advantageous phenotype
a biochemical, physical, or behavioural trait that increases an organism's fitness in its local environment
aerobic cellular respiration
cellular respiration that occurs in the presence of oxygen. Involves three stages, during which glucose and O2 are converted into ATP, CO2, and water
afferent lymphatic vessel
thin-walled structures that collect lymph from the tissues of the body and deliver it to lymph nodes
affinity
the tendency of a molecule/atom to bind or react with another molecule/atom
agarose gel
a sponge-like gel used in gel electrophoresis that contains pores for DNA fragments to move through
agglutination
the clumping of particles together. In the immune system, antibodies can help clump pathogens together
aim
the objective of an investigation or experiment
airborne transmission
the spread of pathogens through air via small particles (traditionally <5 µm)
allele
an alternate form of a gene
allele frequency
the proportion of certain alleles in a gene pool
allergen
a non-pathogenic antigen that triggers an allergic reaction
allergic reaction
an overreaction of the immune system to a non-pathogenic antigen
allopatric speciation
the geographic separation of a population from a parent population resulting in the formation of a new species
allosteric site
a region on an enzyme that is not the active site
alpha helix
an organised coiled secondary structure of proteins
alternative splicing
the process where different exons may be spliced, resulting in a single gene producing multiple different mRNA strands
amino group
the functional group on amino acid molecules that is made up of one nitrogen and two hydrogens (NH2)
amplify
to increase the quantity of a molecule by making many copies
anaerobic fermentation
a metabolic pathway that occurs in the absence of oxygen. Involves glycolysis, followed by further reactions that convert pyruvate into lactic acid in animals, or ethanol and CO2 in yeasts
analogous structures
features present in two or more species that fulfil the same function but do not originate from a common ancestor
anecdote
evidence involving a personal account or report of a previous experience that may provide a certain level of support for a position
personal account or report of a
previous experience that may
provide a certain level of support
for a position"
anneal
the joining of two molecules, for example two complementary DNA strands during the cooling phase of PCR
antibiotic
medications used to kill bacteria or slow their growth
antibiotic resistance gene
gene which confers antibiotic resistance
antibody
a protein produced by plasma cells during the adaptive immune response that is specific to an antigen and combats pathogens in a variety of ways. Also known as immunoglobulin
anticodon
the sequence of three nucleotides on a tRNA molecule that recognises a specific sequence of three nucleotides (codon) on an mRNA strand
antigen
any molecule that may trigger an immune response
antigen-antibody complex
a structure formed by the complementary binding between antigen and antibody molecules
antigen-presenting cell
a subgroup of phagocytes that display the antigens from consumed pathogens on their surface and interact with the adaptive immune system
antigenic drift
small and gradual mutations in the genes encoding for viral surface antigens
antigenic shift
sudden and significant mutations in the genes encoding for viral surface antigens
antimicrobial agent
an agent that kills or slows the growth of microorganisms. Examples include antiseptics, disinfectants, antifungals, antivirals, and antibacterial agents
antimicrobial resistance
the ability of a microorganism to survive exposure to an antimicrobial agent
antiparallel
a characteristic of DNA strands describing how each strand runs in an opposite direction to the other. One strand runs in a 3' → 5' direction and the other runs in a 5' → 3' direction
antiseptic
a substance that is applied to living tissue to kill or slow the growth of microorganisms
antivenom
a medical treatment containing antibodies specific to the toxins present in venomous bites or stings
antiviral
medications used to treat viral infections
apoptosis
the controlled death of cells in the body. Also known as programmed cell death
applied ethics
the application of ethical theories to real-life moral problems and contexts
arable land
land that is suitable for growing crops
arboreal
living in or amongst trees
arm to leg ratio
the ratio of arm length to leg length. Tree-dwelling hominids have longer arms and shorter legs, or a larger arm to leg ratio
artificial active immunity
protection against a disease created by antibodies and memory cells produced by an individual's own immune system after medical intervention. Also known as artificially acquired active immunity
artificial immunity
protection against a disease formed as a result of medical intervention. Also known as induced immunity
artificial passive immunity
protection against a disease created by antibodies from an external medical source. Also known as artificially acquired passive immunity
ATP
adenosine triphosphate, a high energy molecule that, when broken down, provides energy for cellular processes
ATP synthase
an enzyme in the inner mitochondrial membrane that uses the concentration gradient of H+ to synthesise ATP from ADP and Pi
autoantibodies
antibodies directed against an organism's own tissues
autoimmune disease
a disease in which an individual's immune system initiates an immune response against their own cells
autoreactive
a cell that recognises a self-tissue or self-antigen as non-self
B lymphocyte
a type of lymphocyte that plays an important role in humoral immunity and differentiates into plasma cells and B memory cells
B memory cell
a differentiated B lymphocyte that is responsible for providing long-lasting immunological memory of an antigen
bacterial conjugation
the process in which bacteria exchange genetic material via direct cell-cell contact
bacterial transformation
the process by which bacteria take up foreign DNA from their environment. Scientists use this process to introduce recombinant plasmids into bacteria
bacteriophage
a virus that infects prokaryotic organisms
bacterium (pl. bacteria)
a single-celled prokaryotic, microscopic organism that frequently grows in clusters. It can live symbiotically with other organisms and/or act as pathogens
band
a line seen in the gel after running gel electrophoresis that corresponds to a collection of DNA fragments of a specific size
base pair (bp)
a unit of measurement that corresponds to one nucleotide
beneficence
an ethical concept that seeks to maximise benefits when taking a particular position or course of action
beta-pleated sheet
an organised folded secondary structure of proteins
bias
an inclination to favour a particular position or outcome
biochemical pathway
a series of enzyme-catalysed biochemical reactions in which the product of one reaction becomes the substrate of the next reaction. Also known as a metabolic pathway
bioethanol
a type of biofuel that is produced via the anaerobic fermentation of plants such as sugarcane or corn
bioethical approach
a decision-making framework that helps guide ethical behaviour
bioethical issue
an ethical dilemma pertaining to biology that typically involves a decision-making process between two or more choices or options for an action
bioethics
the study of ethical issues pertaining to biology and medicine
biofuel
fuel created from organic material known as biomass
biomass
organic material, including plants, animal by-products, and biological waste material. Biomass can be sourced from many industries, including farming, forestry, and food manufacturing
biped
an individual that moves on two legs (upright-walking)
bipedalism
using two legs for walking upright
block mutation
a mutation that affects a large chunk of DNA, or an entire gene
blunt end
the result of a straight cut across the double-stranded DNA by an endonuclease resulting in no overhanging nucleotides
bone marrow
semi-solid tissue found within bones. Serves as the primary site of the creation of red blood cells and leukocytes
booster vaccine
a vaccination given to a person later in time after they have completed their initial vaccination program to enhance their existing immunity against a disease. Also known as a booster shot
bottleneck effect
the reduction in genetic diversity that occurs when a large proportion of a population is removed due to a chance event
branch
a line on a phylogenetic tree that represents an evolutionary path
brow ridge
a bony ridge above the eye sockets. It is found in all primates, but is greatly reduced in Homo sapiens
buffer
an ion-rich solution that carries electrical current through the agarose gel
bulk transport
a type of active transport that uses vesicles to move large molecules or groups of molecules into or out of the cell
bundle-sheath cell
a plant cell type that is the site of most of the Calvin cycle in C4 plants
C3 plants
plants with no evolved adaptation to minimise photorespiration
C4 plants
plants that minimise photorespiration by separating initial carbon fixation and the remainder of the Calvin cycle over space
