emergent properties
new properties that emerge with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as
... [Show More] complexity increases
negative feedback
a mechanism of response in which a stimulus initiates reactions that reduce the stimulus
positive feedback
a physiological control mechanism in which a change in a variable triggers mechanisms that amplify the change
inductive reasoning
reasoning based on observed patterns
polymer
large compound formed from combinations of many monomers
hydrolysis
a chemical process in which a compound is broken down and changed into other compounds by taking up the elements of water
enzyme
protein that acts as a biological catalyst
phospholipids
a molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail
cellular respiration
process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
phosphorylation
the transfer of a phosphate group, usually from ATP, to a molecule. Nearly all cellular work depends on ATP energizing other molecules by phosphorylation
chemiosmosis
a process for synthesizing ATP using the energy of an electrochemical gradient and the ATP synthase enzyme.
fermentation
the process by which cells break down molecules to release energy without using oxygen
gametes
reproductive cells, have only half the number of chromosomes as body cells
meiosis
a process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in the production of sex cells
somatic cell
cell that makes up all of the body tissues and organs, except gametes
crossing over
the interchange of sections between pairing homologous chromosomes during the prophase of meiosis
transcription
process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in mRNA
codons
a three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code.
RNA splicing
process by which the introns are removed from RNA transcripts and the remaining exons are joined together
mutations
random errors in gene replication that lead to a change in the sequence of nucleotides; the source of all genetic diversity
repetitive DNA
nucleotide sequences, usually noncoding, that are present in many copies in a eukaryotic genome.
transposons
small mobile DNA segments
homeobox
one of various similar homeotic genes that are involved in bodily segmentation during embryonic development
genome project
Research and technology development effort aimed at mapping and sequencing some or all of the genome of human beings and other organisms
adaptations
the behaviors and physical characteristics that allow organisms to live successfully in their environments
natural selection
process by which individuals that are better suited to their environment survive and reproduce most successfully
vestigial structures
remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species
convergent evolution
process by which unrelated organisms independently evolve similarities when adapting to similar environments
protists
single-celled or simple multicellular eukaryotic organisms that generally do not fit in any other kingdom
diatoms
unicellular algae that have a unique glass-like wall made of hydrated silica embedded in an organic matrix
ciliates
a group of protozoans that move by waving tiny, hair-like organelles called cilia
amoeba
A type of protist characterized by great flexibility and the presence of pseudopodia [Show Less]