Bio 182 Exam

• biotic factors are interaction with other organisms such as competition for resources, food, mating, habitat. example: invasive species
• abiotic factors are interactions with nonliving environment such as water, climate, pH, and sunlight
• the three cell model predicts temperature, rainfall, and biome location
• at 20°-30° N and S the air is hot and dry, these are the deserts
• at 45°-55° N and S this is the second zone of precipitation, the tropics
• above 60° the air is dry and cold, these are the arctic tundras
• the greenhouse effect is when solar radiation passes through the atmosphere and heats the Earth's surface, this is necessary to sustain life on Earth
• population density is the number of organisms in a given unit area or volume
• survivorship curves are the rate of mortality over the lifespan of an organism
• type 1 survivorship curve is when there are fewer offspring so that the parents can invest, they die later in life. example: large mammals
• type 2 survivorship curve is when there is a uniform rate of decline example: birds, small mammals, reptiles
• type 3 survivorship curve is when there is a huge decline in young and a greater loss of juveniles, flattens out for those who survive. example: insects and seed plants
• exponential growth is a j-shaped curve used for when resources are unlimited and the density is independent, it keeps growing until carrying capacity is reached, abiotic factors limit the growth
• exponential growth equation is dn/dt=rN where dn is the change in number, dt is the change of time, r is the per capita growth rate, and N is the population size
• logistic growth is s shaped curve used to describe populations with limited resources, as the population grows, competition increases which limits further growth, eventually reaches carrying capacity
• logistic growth equation is dn/dt = rN(K-N)/k where K is the carrying capacity, n is the population size, k is the maximum value of r, and t is the time
• carrying capacity (K) is the maximum population size that can be sustained by an environment
• carrying capacity is determined by food, habitat, etc needed for the individual
• mutualism (+/+) example: intestinal microbes that help us digest
• commensalism (+/0) example: orchids on a host tree
• amensalism (-/0) example: deer trampling vegetation
• competition (-/-) example: rabbit and deer competing for similar resources
• predation (+/-) example: fox eating rabbit
• herbivory (+/-) example: rabbit eats plants
• parasitism (+/-) example: E. Coli in an animal
• Parasitoid (+/-) example: parasitoid wasp lay eggs in caterpillar, hatched wasps eat the caterpillar
• plants move carbon from the atmosphere to the soil by photosynthesis and respiration
• species richness is the number of different species in a community
• species richness varies with latitude, lower latitudes tend to have more and different species than higher altitudes
• the same biome can vary in species richness depending on its location
• a food web shows the complicated relationships of interconnected food chains with multiple links among species
• producers are organisms that make their own food by photosynthesis and are called autotrophs
• consumers get energy from eating other organisms and are heterotrophs
• primary consumers are herbivores that eat the producers
• secondary consumers are carnivores that eat primary consumers
• tertiary consumers are carnivores that eat secondary consumers
• decomposers break down dead organic matter into simpler forms that can be used again by plants or animals
• only 10% of energy is transferred from one trophic to another
• biomagnification is the increase in the concentration of a contaminant in a food chain
• the taxonomic hierarchy order is domain, kingdom, phylum, class, order, family, genus, species