bio old material Flashcards
(26 cards)
hypothesis
a testable explanation for a set of observations based on the available data and guided by inductive reasoning. a hypothesis is a narrower is scope than a theory
theory
an explanation that is broader in scope than a hypothesis generates new hypotheses and is supported by a large body of evidence
oxidative phosphorylation
The production of ATP using energy derived from the redox reactions of an electron transport chain; the third major stage of cellular respiration.
evolution
Descent with modification: the process by which species accumulate differences from their ancestors as they adapt to different environments over time; also defined as a change in the genetic composition of a population from generation to generation.
anabolic pathways
a metabolic pathway that consumes energy to synthesize a complex molecule from simpler molecules
catabolic pathways
a metabolic pathway that releases energy by breaking down complex molecules into simpler molecules
membrane potential
The difference in electrical charge (voltage) across a cell’s plasma membrane due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances.
genes
a discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA
ionic bond
chemical bond resulting from the attraction between oppositely charged ions
hydrogen bond
A type of weak chemical bond is formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule or in another region of the same molecule.
polar covalent bonds
A covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive.
nonpolar covalent bond
a type of covalent bond in which electrons are shared equally between two atoms of similar electronegativity
buffer
a solution that contains a weak acid and its corresponding base. a buffer minimizes changes in pH when acid or bases are added to the solution
active site
the specific region of an enzyme that binds the substrate and that forms the pocket in which catalysis occurs
monomers
the subunit that serves as the building block of a polymer
polymer
a long molecule consisting of many similar or identical monomers linked together by covalent bonds
alleles
any of the alternative versions of a gene that may produce distinguishable phenotypic effects
crossing over
the reciprocal exchange of genetic material between non-sister chromatids during prophase 1 of meiosis
diploid
a cell containing two sets of chromosomes (2n), one set inherited from each parent
haploid
a cell containing only one set of chromosomes (n)
energy of activation
the amount of energy that reactants must absorb before a chemical reaction will start
kinetochore
a structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle
somatic cells
any cell in a multicellular organism except a sperm or egg or their precursors
gametes
a haploid reproductive cell, egg, or sperm that is formed by meiosis or the descendant of cells formed by meiosis. unite during sexual reproduction to produce a diploid zygote
