W1 L1 Flashcards
fossil
the remains or impression of a prehistoric plant or animal embedded in rock and preserved in petrified form.
ontogeny
the branch of biology that deals with the development of an individual organism or anatomical/behavioural feature from the earliest stage to maturity.
phylogeny
(or a tree of life) is a theory about how organisms are related to one another through evolutionary time
ultrastructure
fine structure, especially within a cell, that can be seen only with the high magnification obtainable with an electron microscope.
DNA
molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions of all known living organisms and many viruses
protein
A molecule composed of polymers of amino acids joined together by peptide bonds. C H O and sometimes S
homology
the existence of shared ancestry between a pair of structures, or genes, in different taxa.
paralogy
the divergence of genes within a species
cell
the smallest structural and functional unit of an organism
Domain Archaea
single-celled microorganisms. These microbes are prokaryotes
Domain Bacteria
prokaryotic micro-organisms that have a number of shapes, ranging from spheres to rods and spirals - among the first life forms on earth
Domain Eukarya
organisms whose cells have a membrane bound nucleus
prokaryotic
unicellular organisms that lack organelles or other internal membrane-bound structures. No nucleus so DNA is located in cytoplasm as chromosomes or circular pieces
peptidoglycan
polymer consisting of sugars and amino acids that forms a mesh-like layer outside the plasma membrane of most bacteria, forming the cell wall.
circular chromosome
contain a circular DNA molecule – there are no free ends to the DNA.
