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90 terms

Biology

First Semester Exam
STUDY
PLAY
scientific method
observation or problem, hypohtesis to explain it, test hypothesis, results of test or analyze, draw conclusion, publish
characteristics of all living organisms
made of cells, organized, use energy, homeostasis, growth, reproduction
3 domains
Eukarya, Bacteria, Archaea
autotroph
an organism that makes its own food
heterotroph
an organism that cannot make its own food
eukaryote
A cell that contains a nucleus and membrane bound organelles
prokaryote
A unicellular organism that lacks a nucleus and membrane bound organelles
Thomas Malthus
Eighteenth-century English intellectual who warned that population growth threatened future generations because, in his view, population growth would always outstrip increases in agricultural production
James Hutton
Scottish geologist who described the processes that have shaped the surface of the earth, proposed that the earth is shaped by geological forces that took place over extremely long periods of time estimated the earth to be millions of years old
Jean Baptiste Lamarck
French naturalist who proposed that evolution resulted from the inheritance of acquired characteristics
Charles Lyell
Principles on Geology- the earth is a very old planet that is constantly changing; slowly- gradualism
Alfred Wallace
Naturalist who came to a similar conclusion as Darwin that natural selection could explain the origin of species, biological diversity, and similarities among related life forms.
Charles Darwin
English naturalist. He studied the plants and animals of South America and the Pacific islands, and in his book On the Origin of Species by Means of Natural Selection set forth his theory of evolution
artificial selection
selection by humans for breeding of useful traits from the natural variation among different organisms
population
All the members of one species in a particular area
variations
any difference between individuals of the same species
ecosystem
collection of all the organisms that live in a particular place, together with their nonliving environment
limiting factors
factor that causes the growth of a population to decrease
natural selection
a natural process resulting in the evolution of organisms best adapted to the environment
survival of the fittest
organisms that are most adapted to their environment survive
inherited variation
variation in the parent genes being passed down through genetics
descent with modification
principle that each living species has descended, with changes, from other species over time
embryology
the branch of biology that studies the formation and early development of living organisms
homologous structures
similar structures that related species have inherited from a common ancestor
gene pool
combined genetic information of all the members of a particular population
alleles
one of a number of different forms of a gene
mutations
changes in the genetic material
gene shuffling
the recombination of different genes within the genome
single gene trait
trait controlled by a single gene that has two alleles
polygenic trait
trait controlled by two or more genes
directional selection
form of natural selection in which the entire curve moves; occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve
stabilizing selection
form of natural selection by which the center of the curve remains in its current position; occurs when individuals near the center of a distribution curve have higher fitness than individuals at either end
disruptive selection
form of natural selection in which a single curve splits into two; occurs when individuals at the upper and lower ends of a distribution curve have higher fitness than individuals near the middle
genetic drift
random change in allele frequencies that occurs in small populations
founder's effect
an extreme example of genetic drift; a small part of a population settles in an area far away from the rest of the population, resulting in large amounts of genetic variation.
reproductive isolation
separation of species or populations so that they cannot interbreed and produce fertile offspring
geographic isolation
form of reproductive isolation in which two populations are separated physically by geographic barriers such as rivers, mountains, or stretches of water
behavioral isolation
form of reproductive isolation in which two populations have differences in courtship rituals or other types of behavior that prevent them from interbreeding
temporal isolation
form of reproductive isolation in which two populations reproduce at different times
adaptive radiation
the development of many different forms from an originally homogeneous group of organisms as they fill different ecological niches
convergent evolution
process by which unrelated organisms independently evolve similarities when adapting to similar environments
coevolution
process by which two species evolve in response to changes in each other
adhesion
attraction between unlike molecules
cohesion
attraction between molecules of the same substance
root pressure
The upward push of xylem sap in the vascular tissue of roots.
active transport
the movement of materials through a cell membrane using energy
transpiration
the emission of water vapor from the leaves of plants
mesophyll
The ground tissue of a leaf, sandwiched between the upper and lower epidermis and specialized for photosynthesis (spongy and palisade)
meristematic tissue
plant tissue found only in the tips of shoots and roots; responsible for plant growth
parenchyma
type of ground-tissue cell with a thin cell wall and large central vacuole
stomata
the small openings on the undersides of most leaves through which oxygen and carbon dioxide can move
monocots
angiosperms that have only one seed leaf
dicots
angiosperms that have two seed leaves
hypha
any of the threadlike filaments forming the mycelium of a fungus
mycelium
many hyphae tangled together into a thick mass; comprises the bodies of multicellular fungi
sporangium
organ containing or producing spores
fitness
Charles Darwin called the ability of an organism to survive and reproduce in its specific environment
reproductive isolation
A factor that is necessary for the formation of a new species is
coevolution
A plant evolves a high level of poison that enables it to defend itself against insects. Soon an insect that prefers to eat this plant evolves an enzyme that breaks down the poison. This is an example of
if species living on different islands had once been members of the same species.
Based on the adaptations Charles Darwin observed in finches and tortoises in the Galápagos, he wondered
prevents interbreeding between the populations.
The geographic isolation of two populations of a species tends to increase differences between their gene pools because it
stabilizing selection
Figure 17-2 shows highest fitness toward the center of the curve. When individuals with an average form of a trait have the highest fitness, the result is
knowledge about the structure of DNA.
Darwin's concept of natural selection was NOT influenced by
useful support for his theory.
Charles Darwin viewed the fossil record as
emigration
In a certain population of 100 individuals, one fourth of the individuals have the genotype AA, half have the genotype Aa, and one fourth have the genotype aa. One day, 10 individuals with the genotype aa leave the area and cross a river into a new habitat. Which of these processes has changed the population's gene pool?
non-random mating
Which factor would most likely disrupt genetic equilibrium in a large population?
The population is evolving.
In a fox population, the allele frequency of a gene for red fur changes from 20 percent to 30 percent. What can you say about that population of foxes?
fewer phenotypes
Compared to a polygenic trait, a single-gene trait tends to have
the actions of organisms as they use or fail to use body structures.
Lamarck's ideas about evolution include the concept that differences among the traits of organisms arise as a result of
founders arrived
Which is the first step that occurred in the speciation of the Galápagos finches?
temporal isolation
What situation might develop in a population having some plants whose flowers open at midday and other plants whose flowers open late in the day?
no natural selection takes place
According to the Hardy-Weinberg principle, genetic equilibrium would be more likely in a population of mice if
Mutations have arisen that may have altered allele frequencies.
A farmer sprays insecticide on his crops to kill unwanted insects. Most of the insects die, and the chemicals have the effect of damaging the DNA of the insects that are not killed. Which of these has happened?
chance
In genetic drift, the allele frequencies in a gene pool change because of
the nearly universal genetic code
Molecular evidence in support of natural selection includes
a bell-shaped curve
The frequency of phenotypes for a typical polygenic trait is most often illustrated as
meiosis
During fungal reproduction, which of the following processes is first to occur after the nuclei of opposite mating types fuse in order to reduce the chromosome number back to normal for a fungus?
are often the first organisms to enter barren environments.
Lichens play an important role in soil formation because they
pollen grain
In seed plants, the entire male gametophyte is contained in a
zygomycota
Bread mold belongs to which group?
vessel elements
In angiosperms, xylem consists of tracheids and
old xylem that is no longer conducting water
Which of the following describes the heartwood of a tree?
ovules
In gymnosperms, the female gametophyte develops inside the
are carried to female reproductive structures by wind or animals.
During pollination in seed plants, pollen grains
parallel leaf veins
Unlike a dicot, a monocot has
More oxygen is produced during photosynthesis than the plant needs for cellular respiration, so the plant needs to release the extra oxygen.
If plants need oxygen for cellular respiration, then why do plants release oxygen into the atmosphere?
cause less water to be pulled up from the plant's roots.
The closing of a plant's stomata will
branched veins, flower parts in multiples of 4 and 5, taproot, and rings of vascular tissue
Dicots have
parallel veins, flower parts in multiples of 3, broad fibrous roots, vascular bundles
Monocots have
body space in some invertebrates where digestive and circulatory functions occur.
A gastrovascular cavity is the