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Make up a large, varied group that includes both multicellular and unicellular organisms
containing plant tissue through which water moves up and food moves down
flowering plants that produce seeds in fruit. Most plants are in this category
plants of the class Gymnospermae having seeds not enclosed in an ovary. Pine trees and evergreen are examples
Oldest group of seedless vascular plants that includes club mosses, spike mosses and quillworts (large in Carboniferous period)
Group of seedless vascular plants that includes ferns, horsetails and whisk ferns
A member of the green algal group that are considered the closest relatives of land plants.
Alternate name for land plants that refers to their shared derived trait of multicellular, dependent embryos.
Why are charophytes and embryophytes grouped?
Distinct circular rings of protein that synthesize
Presence of procosomes
Detailed process of Cell division
Advantages of Plants on Land
Initially No Predators
Drawbacks of Plants on Land
Harder to get water
Less structural support that water would otherwise provide
Eventually herbivores exist
Allowed plants to grow tall
Allowed greater intake of sunlight
Farther seed dispersion
seeds not enclosed (pinecone)
Appear 305 MYA
Predominant in Mesozoic
Primarily wind pollinated
First appear 140 MYA
Predominant in Cenozoic
Mainly animal pollinated
considered a stem lineage within the fungi and may be paraphyletic. Contains 1000 species of aquatic and soil dwelling decomposers.
About 16 species. Mold that grows on bread and fruit. Others are parasitic or commensal symbiotes of animals
65,000 species. Marine, terrestrial and aquatic free living parasites that partner in lichens.
form sheaths of hyphae over a root
30,000 species. Shelf fungus such as mushrooms and puffballs. Rarely act as anything other than wood decomposers.
Symbiotic associations between a photoautotroph (either green algae or cyanobacteria) and fungus
organism that uses energy from sunlight to convert carbon dioxide and water to carbon compounds
Photosynthetic, oxygen-producing bacteria (formerly known as blue-green algae).
form associations with vascular plants and can enhance plant growth in soils poor in nutrients.
All animals rose from these
study of interactions that determine the distribution and abundance of organisms
Long term prevailing weather conditions
A major type of biological assemblage defined by chars of the dominant vegetation
the number of individuals per unit area
How Ecologists Measure Density
Count Sample & Extrapolate
Mark and Recapture
Marked/Second Capture=First Capture/Total Population
Position of the individual is independent
Most common. Influenced by resource availability or social interactions
Age specific summary of mortality and fecundity
Proportion of individuals in each age class
Breed multiple times during life span
Breed only once during lifespan
Summary of an organisms tolerances and requirements
Full range of conditions under which a species can survive
portion of niche that species can actually occupy as a result of its interactions with other species
Developed niche concept
niche of a species is determined by the habitat in which it lives
A benefits B is unaffected
A benefits and B benefits
B harmed by A and A harmed by B
Predator/Prey or Host/Parasite
A benefits B is harmed
Different species compete for a particular resource that limits survival and growth
Pioneered competitive exclusion principle
Competitive exclusion principe
Two species that coexist indefinitely on the same limiting resources cannot coexist
Some divergence in resource exploiting traits such as jaws and beaks
Organisms that attain nutrients by ingesting things
Cyclical Population Behavior
When there's a time delay between a consumers ability to increase in number as a result of prey consumption and changes in prey population size.
partners cannot live without one another
Partners can live without one another
Bottom up view
Abiotic nutrients primarily determines a community's structure
Top Down View
Predators limit herbivores, which limit primary producers, which limit uptake of nutrients
happen when control is from the top down and you have effects on top level predators cascading down a food web
Liebig's Law of the Minimum
Growth of an individual or population is limited by the essential nutrients present in the lowest amount relative to the requirement
Only a fraction of production is transferred from one trophic level to the next
Inefficiency of energy transfer along the chain causes food chains to be short
Dynamic Instability Hypothesis
Fluctuations at lower levels of the food chain lead to the extinction of top order predators
Green World Hypothesis
Only a small fraction of Net Primary Production is consumed by herbivores because their populations are kept in check by predators