Unit 1 Review: Vocab Flashcards
Evolution
An orderly succession of changes
Biology
Biology is the study of all living things. All living things are made up of organic compounds, this means they have carbon.
Metabolism
the sum of all the chemical processes that occur in the organism
Homeostasis
Or balance. All living things maintain stable internal conditions. Ex: a cell closely controls its water content by taking in or releasing water (osmosis)
Sexual reproduction
2 parents
Asexual reproduction
1 parent
Spontaneous Generation
living things could arise from nonliving things in a process called spontaneous generation.
Biogenesis
Biogenesis states that all living things come from other living things.
Aerobic
process that requires oxygen to occur
Anaerobic
process that does not require oxygen to occur
Autotroph
organism that obtains its energy from abiotic sources, such as sunlight or inorganic chemicals. An organism that uses energy to synthesize organic molecules from inorganic substances (producer)
Heterotroph
organism that obtains its energy and nutrients by consuming other organisms. Organism that obtains organic food molecules by eating other organisms or their by-products. (consumer)
Prokaryotes
cell that does not have a nucleus or other membrane-bound organelles
Eukaryotes
Eukaryotic cells have a nucleus and other membrane-bound organelles. Prokaryotic cells do not have a nucleus or other membrane-bound organelles.
Photosynthesis
The process by which organisms obtain energy directly from sunlight is photosynthesis
Produces O2
Cellular respiration
Cellular respiration occurs in the mitochondria. and breaks down organic compounds to create energy.
Produces CO2 and H2O
Microspheres
structure spherical in shape and are composed of many protein molecules that are organized as a membrane
Coacervates
collections of droplets that are composed of molecules of different types, including linked amino acids and sugars.
Ozone layer
Ozone absorbs intense ultraviolet radiation from the sun. Ultraviolet radiation damages DNA and without the protection of the ozone layer, life could not have come to exist on land.
Evolution
An orderly succession of changes
Biological evolution
The changes in a population of organisms over generations
Law of superposition
It states that successive layers of rock or soil were deposited on top of one another by wind or water. The lowest layer is the oldest and the top layer is the most recent. This theory gives the history of the Earth. Proposed by Nicolaus Steno.
Adaptive radiation
In adaptive radiation, one form of life spreads to a variety of habitats, separates into isolated groups and evolves into different species over time
Biogeography
The study of geographical distribution of fossils
i.e. moderns kangaroos only in Australia where the now extinct giant kangaroos lived
Fossil
the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.
Natural selection
organisms best suited to their environment survive and reproduce more successfully than other organisms. Thus, over time (perhaps thousands to millions of years) the proportion of organisms with favorable traits increase in a species
Population
all the individuals of a species that live in an area and are capable of interbreeding
Variation
when organisms are born they are not all the same. There is variation (heritable differences that exist among individuals) that exists in every population Natural-selection acts on existing variation and it acts on phenotypes (physical traits (ubservable)
Acquired characteristics
a modification or change in an organ or tissue during a lifetime of an organism due to use, disuse, or environmental effects and NOT inherited.
Adaptive radiation
A type of divergent evolution. Says that many related species evolve from a single ancestral species.
Ex: Finches from the Galápagos Islands. They diverged in response to the availability of different types of food in their different habitats.
Analogous structures
features serve identical functions, and look somewhat alike. They have very different embryological development, however, and may be very different in internal anatomy.
Ex: Hummingbird and humming moth. Both can hover to feed on sugar-rich nectar from flowers. But, there is no anatomical or embryological similarity between their wings. Birds and insects differ greatly in anatomy and embryological development. Although they share a very remote ancestor, their wings evolved independently and differently in more recent ancestors of each animal.
Homologous structures
similar features that originated in a shared ancestor. Homologous features can result from modifications that change an original feature to two different types, such as a wing and an arm.
Ex: The forelimbs of the penguin, alligator, bat, and human all derive from the same embryological structures. Although they look different and vary in function, they have very similar skeletal structures, and derive from the same structures in the embryo.
Coevolution
The change of two or more species in close association with each other. Predators and their prey sometimes co-evolve, parasites and their hosts often coevolve, and plant-eating animals and the plants they feed on also coevolve.
Convergent evolution
Organisms that appear to be very similar, but are not closely related at all. Convergent evolution occurs when the environment selects similar phenotypes, even though the ancestral types were quite different from each other. Analogous structures, such as similar fins in very different animals, are associated with convergent evolution.
Divergent evolution
two or more related populations or species become more and more dissimilar. Divergence is nearly always a response to differing habitats, and it can ultimately result in new species. Ex: Dogs
Vestigial structures
functionless structures that were functional in an ancestral species. A vestigial feature is evidence that the structure was useful to some ancestor.
Ex: Human tailbones, at the end of the spine have no apparent use. The human appendix, a small finger-like projection from the intestine, has no function. Some snakes as well as whales have pelvic bones that have no use. Whales also have a four chambered stomach like a cow.
Artificial selection
Another type of divergent evolution. Sometimes the process of divergence can be sped up artificially, through artificial selection.
Ex: Dogs. All domestic dogs are the same species, Canis familiaris. Dogs have been bred by humans for certain phenotypic characteristics, resulting in different breeds with different traits. The process of divergent evolution with dogs has sped up many times beyond what could have occurred in nature.
Continental drift
German scientist Wegener (in 1912) suggested that the present continents had once been joined in a supercontinent he called Pangaea. He thought that these big land masses were floating apart over the Earth’s hot liquid interior.
Plate tectonics
His hypothesis was not well accepted at the time but is now part of a broader theory called PLATE TECTONICS.
- a scientific theory that explains how major landforms are created as a result of Earth’s subterranean movements
Biological species concept
A species is a population of organisms that can successfully interbreed but cannot breed with other groups
Speciation
Speciation begins with ISOLATION. In isolation two parts of a formerly interbreeding population stop interbreeding.
- Reproductive isolation
- Geographic isolation
Geographic isolation
physical separation of members of a population. This could be caused by continental drift or a deep canyon for example. Once the subpopulations become isolated gene flow between them stops. Natural selection causes the two groups to become less alike. Eventually they are incompatible for mating.
Reproductive isolation
results from barriers to successful breeding in groups in the same area. If the two extremes of a trait are selected for, the organisms may become so different that they are unable to mate. An example of this could be a toy poodle and a Newfoundland dog. The extreme sizes may cause the dog populations to become separate species.
Temporal isolation
exists when timing prevents reproduction between populations. To reduce competition, courtship signs or reproductive periods may change.
Ex: Monterey and Bishop pine have different pollination periods N p 326
Behavioral isolation
isolation caused by different courtship or mating behaviors. Ex: firefly light flashing patterns are specific to each species. N p 325
Extinction
The elimination of a species from Earth is called extinction.
Gradualism
a slow smooth process that occurs over many generations and millions of years.
Punctuated equilibrium
occurs much more quickly (100-1000s of years.) N page 331
