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features that are produced by convergent evolution and are not inherited from a shared ancestor
a group of prokaryotes that are evolutionarily distinct from bacteria and thrive in some of the most extreme environments on Earth
biological species concept
species are populations of organisms that interbreed, or could possibly interbreed, with each other under natural conditions, and that cannot interbreed with organisms outside their own group
populations of organisms living in similar environments experience similar selective forces
a physical state characterized by the ability to replicate and the presence of metabolic activity
a large number of species become extinct over a short period of time due to extraordinary and sudden environmental change
a membrane-enclosed, small, spherical unit containing a self-replicating molecule and carrying information, although no genetic material
all of the individuals are more closely related to each other than to any individuals outside of that group
morphological species concept
characterizes species based on physical features such as body size and shape
error during cell division in plants resulting in a doubling of the number of sets of chromosomes
occur after fertilization and generally prevent the production of fertile offspring from individuals of two different species
make it impossible for individuals to mate with each other, or if they can mate, make it impossible for the male's reproductive cell to fertilize the female's reproductive cell
rapid periods of evolutionary change are punctuated by longer periods with little change
the inability of individuals from two populations to produce fertile offspring with each other
populations that can interbreed with neighboring populations but not with populations separated by larger geographical distances
RNA world hypothesis
the Earth may have been filled with RNA-based life before it became filled with the DNA-based life we see today
a point in evolutionary history at which a given population splits into independent evolutionary lineages
classification process that names and arranges species in a manner that indicates the common ancestors they share and the points at which they diverged from each other
biological entities that can replicate but which can conduct metabolic activity only by taking over the metabolic processes of a host organism and therefore fall outside the definition of life
vascular, seed-producing flowering and fruit-bearing plants, in which the seeds are enclosed in an ovule within the ovary
three groups of plants (liverworts, hornworts, and mosses) that lack vascular tissue and move water and dissolved nutrients by diffusion
an outer waxy layer over the leaf and stem surfaces of plants to keep moisture inside their tissues
two separate fusions of male nuclei from the pollen grain with female nuceli in an ovule to produce an embryo and endosperm
consists of the ovary and some additional parts of the flower that, whose seeds are dispersed by animals after they are eaten
vascular plants that do not produce their seeds in a protective structure, but are usually found on the surface of the scales of a cone-like structure
fungi and chlorophyll-containing bacteria and algae becoming "partners" in mutually beneficial relationships
a multicellular eukaryote that produces its own food by photosynthesis and has an embryo that develops within the protected environment of the female parent
the transfer of pollen from the male part of the flower (anther) to the ovule (female part) of the flower
the part of the plant below ground that is used to obtain water, nitrogen, and salts from the soil
an embryonic plant with its own supply of water and nutrients encased within a protective coating
a single cell containing DNA, RNA, and a few proteins that can land in a moist, sheltered spot and grow into new (haploid) male or female bryophytes
transport water and dissolved nutrients by means of vascular tissue, a system of tubes that extends from the roots through the stem and into the leaves
a layer surrounding the cell wall of many bacteria that may restrict the movement of water out of the cell and thus allow bacteria to live in dry places, such as the surface of the skin
the process by which one bacterium transfers a copy of some of its genetic information to another bacterium, even when the two bacteria are different species
a method of dying the cell walls of bacteria to make them visible under a microscope and is helpful in identifying an unknown bacterium
the accumulation of oxygen released by cyanobacteria beginning 2.6 billion years ago
relatively large particles are engulfed by the plasma membrane, a vesicle is formed, and the particle is moved into the cell
a RNA-containing virus that also contains a viral enzyme called reverse transcriptase that uses a strand of viral RNA as a template to synthesize a single strand of DNA
occurs when a virus called a bacteriophage infects a bacterial cell and passes along new genes to the bacterium
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