Unit 1 Flashcards
What are the two characteristics of a hypothesis?
Must be testable and falsifiable
What is descriptive science?
Describing nature through observation
What is inductive reasoning?
Leads to a generalization based on many observations
What is experimental science?
Explaining nature through experimentation
What is a hypothesis?
A reasonable answer to a well-framed question that leads to predictions that can be tested using experiments
What is deductive reasoning?
If experimental results are consistent with the prediction, they support the hypothesis
What is an independent variable?
The variable being tested
What are matched variables?
Variables that are made the same between controls and experimental groups
What is a dependent variable?
The results
What is a positive control?
You should see a positive result
What is a negative control?
You should see a negative result
Correlation does not indicate…
Cause and effect
How can we conclude something is causal and not just correlated?
Use a controlled experiment
What is a theory?
A major unifying idea with extensive testing and attempts to disprove it have failed
Evolution is a…
FACT-it is measured and observed
What is a scientific fact?
An objective and verifiable observation
What is evolution?
The change in a population or a species over time
What is natural selection?
The process that results in the survival and reproductive success of individuals best adapted to their environment
What is genetic drift?
Random events that can cause some genes to disappear from a population
What is sexual dimorphism?
Males and females have different physical characteristics for non-random mating
What is the order of the hierarchy of biological organization?
Biosphere-Ecosystem/Biome-Community-Population-Organism-Organ-Tissue-Cells
What is ecology?
Study of distribution and abundance of organisms and interactions between organisms and their environment
What is an ecosystem?
Community of organisms in an area and the physical factors with which they interact
How are biomes generally defined?
Type of vegetation (primary producer)
Describe the Tundra.
Northern latitudes, low temperatures, little rain, and mostly composed of mosses and grasses (permafrost restricts plant growth)
Describe the Northern Coniferous Forest (Taiga/Boreal).
Northern latitude, cooler temperatures, a little more rain than the tundra, and has conifers (pine, spruce, fir, hemlocks)
Largest terrestrial biome
Describe a Temperate Forest.
Mid-latitudes, cold winters and warm summers, moderate-high precipitation (seasonal), has deciduous trees (canopy) and a shrub layer
Describe Temperate Grasslands.
Mid-latitudes, rain varies seasonally, cold winters and hot summers, single layer of grasses with large numbers of herbivores
Describe a Desert.
30 degrees above/below equator, low precipitation (highly variable), hot temperatures, sparse, single-layer vegetation (cacti, shrubs, herbs, succulents)
Describe a Tropical Rainforest.
Equatorial, high precipitation, always hot/humid, broadleaf plants/epiphytes with a canopy, sub canopy, and herb layers
What explains the different biomes?
Temperature and precipitation
Why are places along the equator hotter than other places at higher latitudes?
There is more constant, direct sunlight and travels through less atmosphere
Why are seasons more pronounced at higher latitudes?
The tilt of the earth towards and away from the sun
Why are deserts found 30 degrees from the equator?
Moist air rises at the equator and rains on the equator and the cool, dry air sinks 30 degrees from the equator
What are rain shadows?
Mountains near a body of water receive moist temperatures and precipitation on the coast side and dry, cool air on the leeward side
What is an Estuary?
Where freshwater meets salt water
What is the photic zone?
Where light penetrates and photosynthesis can take place
What is the aphotic zone?
Area too deep for light to penetrate
What is the euphoric zone?
Enough light for photosynthesis
What is the dysphotic zone?
Not enough light for photosynthesis
What is the littoral zone?
Shallow zone: shore to depth of photic zone
What is the limentic zone?
Deep, well-lit surface waters
What is the pelagic zone?
The entire water column above the bottom
What is the benthic zone
The sediments at the bottom
What is a thermocline?
Transition between warm, oxygenated, low nutrient H2O and cold low O2, nutrient rich water
What are oligotrophic lake?
Clear, mountain water with low nutrients (not much productivity/growth), O2 rich
What is an Eutrophic lake?
High nutrients, lots of growth, O2 poor
What is lake turn over?
Carrying sediments and nutrients up from the benthic zone
What is an intertidal zone?
Shore between tide lines
What is the neritic zone?
Shallow ocean, low tide line to the continental shelf
What is the oceanic zone?
Open sea
What are tropical estuaries called?
Mangrove Forests
What are temperate estuaries called?
Salt-water marshes
Describe Mangrove Forests.
Roots suspended in water column, efficient nutrient usage, prevent coastline erosion and runoff
Describe Salt Marshes.
Contains emergent grasses and high productivity
Describe coral reefs.
Found in the neritic (shallow) zone, warm but nutrient poor water
Describe Kelp Forests.
Found in neritic (shallow) zone, cool temperate waters
What is population ecology?
Study of how and why the number of individuals in a population changes over time
How do you estimate the population size?
Marked recaptures/total in second sample=marked initially/total population size
What does a exponential model (J-curve) represent?
No immigration/emigration, small population, no competition (resources are unlimited), and conditions do not change
What is the rate of change (r) influenced by?
Age of first reproduction, frequency of reproduction, fecundity (average # of female offspring), length of reproductive lifespan, and survival rate of young
What is type 1 survivorship curve?
Low mortality in young, few offspring and high parental care
What is type 2 survivorship curve?
Equal chance of dying throughout life, less common, some invertebrates and rodents
What is type 3 survivorship curve?
High mortality in young, many offspring, low parental care
