An introduction to ecology and the biophere
chapter 50 objectives
1.) Explain why the field of ecology is a multidisciplinary science.
Ecology is the scientific study of the interactions between organisms and their environments. It involves using observations and experiments to test hypothetical explanations of ecological phenomena. Examining questions from all areas of biology as well as many physical sciences are all part of ecology.
2.) Describe the relationship between ecology and evolution.
Evolution can be described as a change in a population over time. Ecology has to do with organisms and how they interact with their environment. The fact is when a species adapts it can reproduce and continue evolving. There is also the fact that if adapted to one environment and then placed in a foreign one, extinction may result. Both sides affect evolution.
3.) Explain the importance of temperature, water, light, soil, and wind to living organisms.
Environmental temperature affects biological processes (metabolism) and body temperature. Water is essential for life and adaptations for water balance and conservation help determine a species' habitat range. Sunlight provides the energy that drives nearly all ecosystems although only photosynthetic organisms use it directly as an energy source. Wind amplifies the effects of temperature by increasing heat loss by evaporation and convection. The composition of the substrate in a stream or river greatly influences the water chemistry, which in turn influences the plants and animals. The type of substrate influences what animals can attach or burrow in intertidal zones.
4.) Describe how environmental changes may produce behavioral, physiological, morphological, or adaptive responses in organisms.
PHYSIOLOGICAL: After several days to a few weeks the person responds with an increased number of red blood cells being produced and when blood vessels in the skin constrict within seconds to reduce loss of body heat when the skin is exposed to very cold air. BEHAVIORAL: Migratory birds migrate to warmer climates to over winter and Honeybees seal the hive during cold periods to conserve heat and cool the hive on hot days by the collective beating of their wings. MORPHOLOGICAL: Increase in coat fur or feather density in winter and change in coat color between winter and summer.
5.) Describe the characteristics of the major biomes: tropical forest, savanna, desert, chaparral, temperate grassland, temperate forest, taiga, and tundra.
Tropical forest- high temperatures and heavy rainfall. Has a canopy of tall trees with little light reaching the ground below.
Savanna- grasslands with scattered trees. High temperatures but less water then rain forests.
Desert- hot and dry (sparse rainfall)
Temperate grassland- less water and lower temperatures than savannas. Has soil rich in nutrients and mostly called farmland.
Temperate forests- (deciduous) warm summers, cold winters, moderate precipitation. shedding tress during winter as a form of adaptation to poor growing conditions. large trees with sufficient moisture.
Chaparral- dry scrubland found iwhere winters are mild and summers are hot and dry.
Taiga- coniferous forests( i.e- pines,firs,and other tress with needles for leaves). Cold winters and presipitation in the form of snow.
Tundra- during winters the ground freezes. During summer, the upper soil thaws but the deeper soil (permafrost) remains permanatly frozen.
6.) Using a diagram, identify the various zones found in the marine environment.
Found on paper.
Population ecology
chapter 52 objectives
1.) Define the scope of population ecology.
Population Ecology is the study of the growth, abundance, and distribution of populations.
(density and dispersion)
2.) Distinguish between density and dispersion.
Population density is the number of individuals per unit area. Population dispersion is the pattern of how individuals within a population are spread out.
3.) Explain how ecologists measure density of a species.
Density = population (# of individuals) / area
4.) Explain how age structure, generation time, and sex structure of populations can affect population growth.
5.) Describe the characteristics of populations, which exhibit Type I, Type II, and Type III survivorship curves.
Type I- species in which most individuals survive to middle age.(humans)
Type II- length of survivorship is random, like likelihood of death is the same at any age. (rodents)
Type III- species in which mosy individuals die young, with only a relative few surviving to reproductie age and beyond.(oysters and toher species that produce free-swimming larvae that make up a component of marine plankton).
6.) Explain how density-dependent factors affect population growth.
Examples of density-dependent factors are resource depletion, competition, and predation. These effects become more intense as the population density increases.
7.) Describe how weather and climate can function as density-independent factors in controlling population growth.
Weather and climate function as density-independent factors because they affect the population regardless of the density of the population.
8.) Explain how density-dependent and density-independent factors may work together to control a population's growth.
Extreme climate may result in resource depletion making the population struggle to survive.
9.) List the three major characteristics of a life history and explain how each affects the: a. Number of offspring produced by an individual b. Population's growth
10.) Explain how predation can affect life history through natural selection.
11.) Distinguish between r-selected populations and K-selected populations.
R-selected populations colonize an area that is barren or uninhabited. They reproduce quickly to ensure their survival. K-selected populations settle in a stabilized environment. They tend to be large animals with long lifespans, so they produce few offsprings.
community ecology
chapter 53 objectives
1.) Explain the relationship between species richness, relative abundance, and diversity.
The species diversity withinh a community would be an assemblence of species living close enough together for potential interaction between the # of species (richness) and the quantiy of the species (abundance).
2.) List four properties of a community, and explain the importance of each.
1) Competitive exclusion principle- when two species compete for exactly the same resourse and one species is more likely to be successful.
2) Resourse partitoning- Species that coexist in spite of apparant competition for the sameresourse( i.e- frogs feeding on different insects of the same pond)
3) Character displacement- certain individuals may obtain resources in their partitons. (due to evolution two birds witht he same beaks now have slightly different beaks which allows them to find different food to survive).
4) Realized niche- that part of their existence where the niche overlap is absent and they do not compete for the same spcies.
3.) Explain how interspecific competition may affect community structure.
Both population densities may increase (+ / +), one may increase while the other decreases (+ /-), one may increase while the other is not affected (+ / 0), or both may decrease (- / -).
4.) Describe the competitive exclusion principle, and explain how competitive exclusion may affect community structure.
The principle states that 2 species cannot coexist in the same community if their niches are the same. This may lead to extinction of the weaker competition or adaptation of one species to a new niche, however it will not last long.
5.) Distinguish between an organism's fundamental niche and realized niche.
A fundamental niche is the resources a population is theoretically capable of using under ideal circumstances. Biological constraints (competition, predation, resource limitations) restrict organisms to their realized niche: the resources a population actually uses.
6.) Distinguish between Batesian mimicry and Mullerian mimicry.
Batesian mimicry- occurs when an animal without any special defense mechanism mimics the coloration of an animal that does possess a defense.
Mullerian mimicry- occurs when several animals, all with some special defense mechanism, share the same coloration.
7.) Explain the role of predators in community structure.
Any animal that totally or partly consumes a plant or another animal.
8.) Distinguish among parasitism, mutualism, and commensalism.
Parasitism is a parasite that lives on or in a host taking nourishment from it but not killing it immediately. Mutualism co-evolve (both species benefit). Commensalism is when one species benefits and the other is not affected.
9.) Distinguish between primary succession and secondary succession.
Primary Succession: no life then there is life
Secondary Succession: there is life, then no life, then it rebuilds.
chapter 54 objectives
1.) Explain the importance of autotrophic organisms with respect to energy flow and nutrient cycling in ecosystems.
2.) List and describe the importance of the four consumer levels found in an ecosystem.
Producers: make their own food
Primary Consumers: eat producers
Secondary Consumers: eat producers and primary consumers
Tertiary Consumers: eat all of the above
3.) Explain how gross primary productivity is allocated by the plants in an ecosystem.
4.) Explain why productivity declines at each trophic level.
5.) Distinguish between energy pyramids and biomass pyramids.
6.) Describe the carbon cycle, and explain why it is said to result from the reciprocal processes of photosynthesis and cellular respiration.
The carbon cycle is required for the building of all organic compounds.
Reservoirs- atmosphere, fossil fuels, peat, durable, organic materials
Assimilation- plants that use carbon in photocynthesis, like when animals consume plants or other animals.
Release- plants and animals realese carbon through respirationand decomposition.
7.) Describe the nitrogen cycle, and explain the importance of nitrogen fixation to all living organisms.
The nitrogen cycle is required for the manufacturing of all amino acids and nucleic acids.
Nitrogen fixation id the transfering nitrogen by lightning and uv radiation.
8.) Explain how phosphorus is recycled locally in most ecosystems.
Phosphorus is recycled by: (then statrs all over again0
Reservoirs- mainly rocks in which erosion transfers phosphorus to water and soil. sediments and rocks that accumulate on ocean floors return to the surface as a result of of liftning by geological processes.
Assimilation- plants absorb inorganic phopherus from soils.
Release- plants and animals release phophorus when they decompose.
9.) Describe how the carbon cycle differs in terrestrial and aquatic systems.
10.) Describe how increased atmospheric concentrations of carbon dioxide could affect the Earth.
11.) Describe how human interference might alter the biosphere.
Human activity damages the biosphere. Exponential growth, destruction of habitata for agrculture and mining, pollution from industry and tranportation, and many other activities all contribute to the damaging or altering of the enviroment.