Bio 1050 unit 4
Terms in this set (74)
The inability to mate and produce fertile offspring
a slight change in allele frequencies over one or a few generations
the accumulated effect of micro evolution over a long period of time
life on earth most likely originated from non-living materials
individuals are physically unable to mate with each other
if individuals are able to mate the males reproductive cell is unable to fertilize the females reproductive cell.
Mating's produce hybrid individuals that do not survive long after fertilization
If hybrid offspring survive, they are infertile or have reduced fertility.
does the biological species concept always work?
No it works with most plants and animals but not all distinguished life forms
organization of life in order
humans are classified as primates T/F
A large number of species become extinct over a short period of time due to extraordinary and sudden environmental change.
These extinctions occur at lower rates during times other than mass extinctions
The study of how populations interact with their environments
The study of interactions between organisms and their environments.
Occurs when each individual produces more than the single offspring necessary to replace itself.
Density dependent factors
The limitations on a population's growth that are a consequence of population density
Describes population growth that is gradually reduced the population nears the environment's carrying capaciy
R-selected: many offspring with little care
K-selected-Few offspring, but you put energy into making sure that they reach reproductive age.
Survivorship decreases at regular pace
High mortality early in life
A pattern of population growth that is experienced as a country industrializes. Characterized by slow growth, then fast growth, and then slow growth again.
Evaluating how much land, how much food and water, and how much fuel, among other things, are necessary
Density Independent factors
Severe weather, such as drought or very high or low temperatures.
has living and Nonliving Components.
Biotic and Abiotic components.
-The living organisms within an area
-often referred to as a community
-The chemical resources and physical conditions within an area
- Often referred to as the organisms' habitat.
-Determined by temperature and precipitation
-Defined by dominant form of vegetatoin
Impacted by: -Latitude
-Proximity to water
Determined by temperature, depth and salinity, flow
-Aquatic species are more sensitive to temperature changes
-Depth and water clarity determine the amount of light penetration.
what we expect
what we get
Energy flow within an ecosystem
1) Primary Producers
Plants Convert light energy from the sun into food through photosynthesis.
Herbivores are animals that eat plants
Carnivores are animals that eat herbivores.
Top Carnivores are animals that eat other Carnivores.
Decomposers, and Detritivores
Break down organic wastes, releasing chemical components that can then be reused by plants and other primary producers.
First Law of Thermodynamics
Energy cannot be created or destroyed
Second Law of Thermodynamics
With EVERY transfer of energy, the quality of the energy decreases
Less organized energy (such as body heat) is not very useful outside of the organism (it cannot be used to do work).
energy pyramid flow order
what percent of biomass is passed down by consumers on the energy pyramid?
10% of the biomass from each trophic level is converted into biomass in the next trophic level.
Three Most Important Chemical Cycles
Plants use carbon molecules from atmospheric carbon dioxide and light energy from the sun to build sugars through photosynthesis
Nitrogen gas, which has a chemical structure completely unusable by most organisms, is "fixed" by soil-dwelling bacteria, producing ammonia and other compounds containing nitrogen.
Plant absorb phosphorus through their roots in the form of phosphate.
the increase in nutrients in an ecosystem, particulary nitrogen and phosphorus-often leads to the rapid growth of algae and bacteria in lakes and other aquatic ecosystems.
Such as the sea star, has an unusually large influence on the presence or absence of numerous other speciaes in the community. when sea stars were removed from an area within an intertidal zone, species diversity decreased drastically-only mussels remained.
A group of chemicals that behave like hormones in the body
Found in everyday products such as plastic water bottles
Found in our food as pesticide residues
A large number of species bec
The extinction that occurred on earth 65 million years ago and wiped out the dinosaurs was immediately followed by:
the rapid divergence and radiation of modern mammals.
Which of the following is the MOST species-rich terrestrial biome?
A. tropical rain forests
Fossil fuels are composed largely of:
C. hydrogen and carbon.
What does it mean to say that a species is endangered?
A. That species is in imminent danger of extinction.
"Ecological succession" refers to:
B. a series of predictable changes in the composition or structure of an ecological community.
A driving force behind ocean currents is:
Which of the following is NOT an important greenhouse gas?
D. sulfur dioxide, SO2
Even though there is a carbon cycle, it now appears that carbon dioxide levels are rising around the world. Which of the following best explains why this is true?
B. The burning of fossil fuels releases more carbon dioxide into the atmosphere.
Cold deserts generally exist at:
C. 90 degrees N and S latitude.
The total dry weight of all organisms in an ecosystem is called its:
Which of the following BEST defines a biome?
D. areas with distinct plant communities and associated with particular climates
The distribution of terrestrial biomes across the globe corresponds MOST to which of the following?
The main source of energy that drives global climate is:
B. solar energy.
Wind circulation patterns are driven by:
D. the uneven heating of earth's surface.
_____ and _____ are the major factors that determine climate.
C. Temperature; precipitation
Most of the deserts of the world occur:
C. at 30 degrees North and South latitude.
What is the main reason(s) the tropics are warmer than the poles?
A. The suns rays hit the earth directly at the equator but hit the poles at an angle; this concentrates the solar energy over a smaller area at the equator than at the poles.
Why are many deserts located on the backside of mountains?
D. Moist air masses are forced to rise over mountains and lose their moisture in the process resulting in very little moisture availability for the other side of the mountain.
Without ocean currents such as the Gulf Stream, the climate of the UK would:
C. be similar to that of the Mediterranean (warmer).
Roughly how much energy in a trophic level is available to the next trophic level?
If a food chain consisted of grass to rabbits to foxes, how many pounds of foxes could be expected in a meadow which has 10,000 pounds of grass?
Most of the carbon in the earth's atmosphere exists as:
D. carbon dioxide, CO2.
Over the last 200 years, the amount of CO2 in the air has:
A. increased because the amount of photosynthetic biomass has decreased.
Which of the following nutrient cycles has the smallest atmospheric component?
D. the phosphorus cycle
Currently, the major threat to most large, land mammals is:
B. habitat loss
A. play an unusually important role in determining the species composition in a habitat.
Which of the following is the MOST species-rich terrestrial biome?
D. tropical rain forests
Planting trees can combat global warming, because:
A. photosynthesis from those trees absorbs CO2, a greenhouse gas, from the atmosphere.