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The definition of your carbon footprint is __________.
the amount of greenhouse gas emitted as a result of your actions
What special circumstances are required to keep the gene pools separated in sympatric speciation?
What are prezygotic barriers? Know the 5 types.
Prezygotic barriers prevent mating or fertilizationbetween species.
- Temporal isolation- Species mate at different times
- Habitat isolation
- Behavioral isolation
- Mechanical isolation
- Gametic isolation
Postzygotic barriers prevent survival or reproductionof hybrid offspring.
- Hybrid inviability- offspring fails to completedevelopment, never allowing gene pools to overlap.
- Hybrid sterility- offspring are sterile and cannotreproduce.
- Hybrid breakdown- first generation may be viable andsterile, but genetic factors cause the next generation to be weak, sterile,etc.
Know the 8 classification levels for human beings.
What are abiotic factors? Know the 5 examples.
Energy source, temperature, water, wind, rocks and soil
· Animals, Bacteria, Plants
What are 3 types of adaptations that enable organisms to adjust to changes in their environment?
Name 2 types of Aquatic Biomes? What is the salinity of each?
· Freshwater- a salt concentration less than 1%
· Marine- usually a salt concentration ~3%
· Standing water- lakes and ponds
· Flowing water- rivers and streams
What are wetlands?
· Transitional biome between aquatic and terrestrial ecosystems.
· Area where water and land come together, very divers in species.
What are estuaries?
· Area where a freshwater stream or river merges with the ocean.
What is population density?
The number of individuals of a species per unit of area or volume. It is very hard to give an exact number on population density, so its usually an estimate.
Animals are trapped, marked, and recaptured after a period of time in order to study changes in their population, evolution.
What is the age structure of a population? Why is it utilized?
- The age structure of a population is the proportion of individuals in different age groups.
- It can help us understand the history of a population’s survival or reproductive success and how it relates to environmental factors.
- Also a useful tool for predicting future changes in a population
What are the 2 growth models? Know what each one lookslike on a graph.
Exponential and Logistic
What is a community?
An ecological unit composed of a group of organisms or a population of different species occupying a particular area, usually interacting with each other and their environment.
What did G. F. Gause study? What model organism did heutilize?
Gause studied the effects of interspecific competition. He used two closely related protists known as paramecium.
What were his results?
Gause concluded that two species so similar that compete for the same limiting resources cannot coexist in the same place. Basically, two species cannot coexist in the same community if their niches are identical.
What does the competitive exclusion principle state?
That if two similar species are competing for the same ecological niche….
- A) One will become extinct OR
- B) One species will evolve to utilize different resources
What are some of the plant defenses against herbivores?
Spines, thorns, chemical toxins, or chemicals, which make a plant taste bad.
What are some of the animal defenses against predators?
The defense categories include passive, active, and mechanical
Why do organisms enter into symbiotic relationships?
Organisms enter into symbiotic relationships because both organisms benefit from there relationships. Sometimes these relationships are crucial to both organisms survival.
What types of symbiotic relationships are there?
Mutualism- both benefit
Commensalism- one organism benefits, while the other is not affected
Parasitism- one organism benefits, while the other is harmed.
Why is biodiversity important?
Biodiversity is important to humans because we rely on it for food, clothing, shelter, oxygen, fertile soil, and medicine.
Why does energy flow, but nutrients cycle?
Energy flows when consumers eat producers, and it is unable to be recreated and put back into the environment.
What factors increase the loss of biodiversity?
Biodiversity is the degree of variation of life forms within a given species, ecosystem, biome, or an entire planet.
What is species richness? What is relative abundance?
Species richness is the total number of different species in the community
Relative abundance of the different species
What was the name of the publication that Darwin published? In what year was it published?
On the Origin of Species by Means of NaturalSelection, 1859
What is the basic idea of natural selection?
The result in evolutionary adaption.
What is the result of natural selection?
Darwin based his theory of natural selection on two key observations. What are the two observations?
Overproduction- organisms produce to many offspring, creating struggle
Individual Variation- variation exists among individuals in a population due to trains passed by ancestors.
What is unequal reproductive success?
Individuals with trains best suited for their environment leave the most fertile offspring.
What are homologous structures? Know examples we talked about.
Is the similarity in structures due to common ancestry
What is biogeography?
The study of geographic distribution of species. Species are made for their environment, and this supports Darwin’s ideas.
What is comparative anatomy?
Comparison of body structure between species, which confirms evolution as a remodeling process.
What is comparative embryology?
Comparative embryology is the comparison of structures that appear during the development of different organisms.
What is a fossil? How are fossils formed?
Fossils are preserved remnants or impressions left by organisms that lived in the past, which are often found in sedimentary rocks. They are usually created by river beds
Where are fossils found?
In rock layers, which allows scientists to determine their age.
What is sexual recombination?
The shuffling of alleles during meiosis.
What is directional selection? What does the phenotypic graph look like compared to the original population curve?
Shifts the phenotypic “curve” of a population
Selects in favor of some extreme phenotype
What is disruptive selection? What does the phenotypic graph look like compared to the original population curve?
Can lead to a balance between two or more contrasting morphs in a population.
What is stabilizing selection? What does the phenotypic graph look like compared to the original population curve?
Maintains variation for a particular trait within a narrow range
all of the ecosystems of the earth
A system that includes all living organisms (biotic factors)in an area as well as its physical environment (abiotic factors) functioning together as a unit
an ecological unit composed of a group of organisms ora population of different species occupying a particular area, usually interacting with each other and their environment.
What is a geographic range?
A geographic area in which a specific species can be found.
Define biotic potential.
The maximum reproductive capacity of a population if resources are unlimited. It is basically when a population experiences unlimited growth.
What is an exponential growth curve? What shape is this curve?
Describes the rate of expansion of a population under ideal, unregulated conditions.
What is the rule of 72?
The rule of 72 is how long it takes a certain population to double in size.
Name 5 factors that have increased the biotic potential for humans.
· Hearty food supply
· Education / Technology
Define growth rate.
The rate or speed at which the number of organisms in a population increases.
The relationship between a species and all the biotic and abiotic factors affecting it.
Define the competitive exclusion principle.
Two species cannot coexist in a community if their niches are identical.
What is a biological pyramid?
shows the flow of energy from one level of the food wed to the next.
What is eutrophication?
Chocking of rivers, lakes and other waterways by excess algae growth which has been stimulated by fertilizers or sewage.
How much energy is available to the next level in a biological pyramid?
1/10 of the energy available to the previous level of the biological pyramid.
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