BIO 103- Exam 3 Flashcards
biodiversity connected
no organism lives alone, all organisms have ecological relationships with other organisms (direct or indirect), all organisms have ecological relationships with their environment, all organisms interact to form populations, communities, ecosystems, and biomes
population
group of individuals of the same species that inhabit a specific region and interact with each other
community
populations of different species that live within a specific region and interact closely with each other
ecosystem
all living and non-living things in a region that interact with each other
how is energy passed from one feeding level to another?
sun (chemicals), autotrophs, herbivorous heterotrophs, carnivorous heterotrophs
what do producers need to survive?
source of energy (sunlight or chemicals) and nutrients (detritus, inorganic chemicals)
trophic levels
feeding levels or energy levels, energy is lost as you go up the levels (producers with the most energy)
producers
make their own food, autotrophs
consumers
heterotrophs (primary, secondary, tertiary)
detritus
dead organic matter
decomposers
heterotrophs that derive their energy from detritus
food chain
path of energy flow across trophic levels, linear
food web
a visual map of feeding relationships and energy flow among organisms in a community, network
competition
multiple organisms seek the same limited resource (ex: food, water shelter), negative effect on both species
intraspecific competition
competition between members of the same species
interspecific competition
competition between members of different species
exploitation
one member benefits while the other is harmed
predation (exploitation)
process by which individuals of one species (predators) capture, kill, and consume individuals of another species (prey), cyclic process
parasitism (expolitation)
a relationship in which an organism (parasite) depends on another (host)
herbivory (expolitation)
animals feed on the tissues of plants, affects growth and reproduction
defenses against herbivory
chemicals (toxic or distasteful), physical structure (thorns, spines)
mutualists
two or more species benefit from their interacts
symbiotic relationship
two species live in close association with each other and depend on each other mutually for their survival
pollination
interactions between plants and animals that result in plant pollination
human microbiome
the complete collection of microorganisms in the human body’s ecosystem, important for nutrition and immunity
symbionts
organisms that have mutual relationships with another organism
keystone species
species that have a dramatic effect on an ecosystem and community disproportionate to its abundance, usually top predators, effect on community and ecosystem via predation and intermediate trophic level
ecosystem engineers
species that physically modify the environment
alien (exotic) species
non-native species from somewhere else enters a new community, introduced deliberately or accidentally
invasive species
non-native species that spreads widely and becomes dominant in a community, growth limiting factors are absent, have major ecological effects
disturbance
an event that destroys all or part of life forms in a region (fire, floods, earthquakes)
succession
the predictable series of changes in a community after a severe disturbance
primary succession
occurs after a disturbance removes all vegetation and social life (glaciers, drying of lakes, volcanos, strip mining)
pioneer species
the first species to arrive in a primary succession area (lichens), early colonizers produce organic matter which leads to the creation of soil
climax community
remains in place with few changes until another disturbance restarts succession
secondary succession
occurs after a disturbance has removed much, but not all, of biotic community (fires, hurricanes, logging, farming), soil still contains most of its nutrients and organic matter, revegetated by trees and bushes
ecosystems
result from the interactions of ecological communities and abiotic environment
- biological entities are tightly intertwined with chemicals and physical parts of the environment
- all biotic and abiotic entities that live and interact in a particular area at the same times
productivity
how much biomass in accumulated over time (generally primary production)
nutrients
any element or molecule that organisms require to grow, survive, and reproduce
non-mineral nutrients
carbon, hydrogen, oxygen
mineral nutrients
mainly nitrogen, phosphorus, potassium, magnesium, calcium (aka primary macronutrients/fertilzers)
eutrophication
excess nutrients/nutrients pollution in aquatic systems (increase growth of algae)
hypoxia
depletion of oxygen, loss of fish and invertebrates
anoxia
no oxygen
biogeochemical cycles
matter (nutrients) cycles through biological and geological entities via chemical reactions
pools( reservoirs)
where nutrients reside for varying amounts of time (the residence time)
source
a pool that releases more nutrients than it accepts
sink
a pool that accepts more nutrients than it releases
flux
the rate at which materials move between reservoirs (can change over time, can be influences by human activity)
the carbon cycle
the organic circulation of carbon from the atmosphere into organism and back again
variety
different traits within the same species, also called “morph”
breeds
refers to varieties within a species of domesticated animals
evolution
change in average value of a heritable trait in populations over one or more generations
what was wrong with Lamarck’s theory of evolution?
he suggest that organisms can alter their traits based on need and he proposed that organisms passed on traits they acquire over their lifetime
evolution by natural selection
the process in which the environment determines which individuals survive and reproduce
when does natural occur?
heritable traits, variation in traits, not all individuals are equally successful at survival and reproduction
biological fitness
measure of an individuals contribution to the next generations gene pool, measured by the number of fertile offspring produces in the lifetime of an individual
mechanisms of evolution
mutation, gene flow, genetic drift, natural section/sexual selection
mutation
random changes in an individuals DNA, occurs due to mistakes during DNA copying
types of mutations
neutral (no effect on fitness)
deleterious (mutation may quickly be removed from population)
beneficial (mutation may increase in frequency over time)
gene flow/migration
movement of genes in or out of a population due to interbreeding after migration
genetic drift
change in the genetic make-up of the population due to random chance
sexual selection
a form of natural selection in which individuals with certain inherited characteristics are more likely than others to obtain mates
artificial selection
mechanism of evolution under domestication, humans “select” desired traits, and weed out undesired traits
principles of natural selection
variation, overproduction, adaptation, descent with moditification
descent with modifitication
principle that each living species has descended, with changes, from other species over time
common descent
principle that all living things were derived from common acestors
adaptive trait (adaption)
trait that provides high fitness to the individual in a specific environment
selection versus evolution
selection is the filtering process while evolution is the result of natural selection
sexual selection for males
finding and keeping mates is the most important for fitness
sexual selection for females
survival, nutrition to produce offspring, and offspring for survival is most important for fitnesss
sexual dimorphism
morphological differences between the sexes of the same species
male dimorphism
develop traits that help them increase fitness by finding and keeping mates
female dimorphism
develop traits that help increase fitness by increasing nutrition and offspring survival
ornaments
attractive traits that increase mating success
armaments
weaponry used to outcompete other individuals
speciation
the creation of new species from existing species
species
a group of organisms that are able to interbreed successfully in nature, produce viable/fertile offspring and are reproductively isolated from other species
how do you define two populations as different species?
individuals of different populations cannot interbreed naturally, if they do interbreed the offspring will be infertile or do not survive.
microevolution
evolution within a population over a small time scale
macroevolution
evolution over the species level, over larger time scale
reproductive isolation
the existence of biological factors that impede members of two different species from producing viable, fertile offspring
prezygotic barries
prevent species from combining gametes (before-zygote)
posttzygotic barries
prevent hybrids from reproducing and mixing genes of the two species
examples of prezygotic barries
habitat isolation, temporal isolation, and mechanical isolation
examples of postzygotic barriers
reduced hybrid fertility
evolutionary medicine
the application of the theory of evolution to understanding health and human conditions in attempt to treat people effectively
allergies
immune system attacks harmless substances, immune response against non-pathogens
auto-immune condition
immune system attacks body’s own tissue
where is there a high prevalence of allergies and auto-immune conditions?
western countries/westernized world
the hygiene hypothesis
insufficient exposure to microbes can lead to allergies and autoimmune disease due to insufficient “database” for immune system to work with
why do we get a fever?
fever is an adaptive defense against pathogens, treating the fever will make the infection worse
why and how do bacteria develop resistance to drugs
bacteria have evolved in ways to survive antibiotics through random mutations of resistance
alexander fleming
discovered penicillin in 1928
mutations in bacteria
vertically (parent to offspring) or horizontally (one individual to another)
natural selection in bacteria
random mutations lead to resistance, individuals with the resistance gene are favored and multiply in future generations
viruses
have specific proteins on the surface and are specific to virus strain
different types of vaccines
attenuated (weakened virus)
closely related harmless virus modified to produce protein of pathogenic virus
RNA with information to produce to protein of the virus
how do vaccines work?
vaccine is introduced allowing for the immune system to produce antibodies that recognize the proteins of the virus
