Unit 2: Energy in the Environment

The first law of thermodynamics says…
Energy cannot be created or destroyed.
If there are 50 births and 30 deaths in a population of 1000 people, what is the % population change?
2 %
Define: energy
The capacity to do work by performing mechanical, physical, chemical, or electrical tasks or to cause a heat transfer between two objects at different temperatures.
Energy Quality
Ability of a form of energy to do useful work.

Low temp heat -> low quality energy
High temp heat -> high energy quality

The 2nd law of thermodynamics says…
In any conversion of heat energy to useful work, some of the initial energy input is always degraded to a low-quality, more dispersed less useful energy (usually low temp)
Photosynthesis Equation
6CO2 + 6H2O ==> C6H12O6 + 6O2
Define: Photosynthesis
Complex process that takes place in cells of green plants.
Radiant energy from sun is used to combine CO2 and water (H2O) to produce oxygen and carbohydrates (such as glucose, (C6H12O6).
Define: Respiration (aerobic)
Complex process that occurs in the cells of most living organism, in which nutrient organic molecules such as glucose (C6H12O6) combine with oxygen and produce carbon dioxide and water and energy.
Biomass
Organic matter produced by plants and other photosynthetic producers; total dry weight of all living organisms that can be supported at each trophic level in a food chain or web.
Define: Trophic Level
All organisms that are the same number of energy transfers away from the original source of energy.
Define: Food Web
Complex network of many interconnected food chains and feeding relationships.
Define: Food Chain
Series of organisms in which one eats or decomposes the preceding one.
Define: Ecosystem
Community of different species interacting with one another and with the chemical and physical factors making up its nonliving environment.
Define: Population
Group of individual organisms of the SAME species living within a particular area.
Define: Community
Populations of ALL species living and interacting in an area at a particular time.
Pyramid of Numbers
A diagram representing the number of organisms of a particular type that can be supported at each trophic level from a given input of solar energy at the producer trophic level in a food chain or food web.
Pyramid of Energy
A diagram representing the flow of energy through each trophic level in a food chain or food web.

Typically 10% energy transferred to organisms in each energy transfer

Pyramid of Biomass
A diagram representing the biomass or total dry weight of alll living organisms that can be supported at each trophic level in a food chain/web.
Habitat
A place or type of place where an organism or population of organisms live
Biotic Factors
The living organisms that make up the biotic parts of the ecosystem.
Abiotic Factors
Nonliving component of an ecosystem.
Ecotone
Transitional zone in which one type of ecosystem tends to merge with another ecosystem.
Ecology
Study of the interactions of living organisms with one another and with their non-living environment of matter and energy; study of the structure and functions of nature.
Niche (ecological)
Total way of life or role of a species in an ecosystem. includes all physical and biological conditions a species needs to live and reproduce in an ecoystem.
Fundamental Niche vs. Realized Niche
A fundamental niche is the full potential range of the physical, chemical, and biological factors a species can use if there is no competition from other species whereas a realized niche is parts of the fundamental niche of a species that are actually used by that species.

Fundamental (potential) it rhymeees
Realized (what is actually used)

Keystone Species
species that play roles affecting many other organisms in an ecosystem
Indicator species
a species that serve as early warnings that a community or an ecosystem is being degraded
Specialist species
species with a narrow ecological niche.
1. only able to live in one type of habitat
2. not very tolerable to climate change
3. use only one or few types of foods
Generalist species
opposite of specialist (broad ecological niche)
r-selected species
1. reproduce early
2. lots of offspring, don’t raise them
3. small life span
K-selected species
species that produce a few, often fairly large offspring and raise them to reproduction age
carnivore
animal that feeds on other animals
omnivore
animal that can use both plants and other animals as food sources
scavenger
organism that feeds on dead organisms that were killed by other organisms/died naturally
producer
organism that uses solar energy (green plant) or chemical energy (bacteria) to manufacture the organic compounds it needs as nutrients from simple inorganic compounds
herbivore
an organisms that only eats plants
detritivore
consumer organism that feeds off parts of dead organisms and wastes of living organisms
natural selection
process by which a particular beneficial gene is passed down through younger generations making it easier for them to adapt to certain environmental conditions
biodiversity
variety of dif. species
What is the formula for GPP?
GPP = NPP + Respiration
What is the formula for Respiration?
Initial dark – dark final
Formula for NPP?
light final – light initial
Range of Tolerance
range of chemical and physical conditions that must be maintained for populations of a particular species to stay alive and grow
What is the GPP?
The gross primary productivity aka the rate at which an ecosystem’s producers capture and store a given amount of chemical energy as biomass in a given length of time.
Logistic Growth
involves exponential population growth when the population is small and a steady decrease in population growth with time as population encounters environmental resistance
How have some species reduced/avoided competition?
resource partitioning
Resource partitioning
dividing up of scarce resources so that species with similar needs use them at different time, in different ways or in different places
Predation techniques
pursuit and ambush, hide and ambush, camouflage, chemical warfare
Mutualism
When 2 species involved in a symbiotic relationship interact in ways that benefit both of them
Commensalism
When 2 species involved in a symbiotic relationship interact in ways that benefits one and doesn’t affect the other
Parasitism
When 2 species involved in a symbiotic relationship interact in ways that benefits one and HARMS the other
Amensalism
When 2 species involved in a symbiotic relationship interact in ways that harms one and doesn’t affect the other (ex. an elephant stomps on some plants)
Predation
members of one species feed directly on another
Competition
sometimes one species eliminates another species in a particular area through competition for limited resources
If there are 60 births and 20 deaths in a population of 1000 people, what is the % population change?
4 %
What type of pyramid always looks the same?
Pyramid of energy (Big on bottom -> smaller)
Net Primary Productivity represents…
1. plant growth per unit area per unit time
2. energy available per unit area per unit time
3. the energy available to herbivores
4. the amount of biomass remaining after some depletion by a plant’s cellular respiration
If a population grows at a MONTHLY rate of 4 %, what is the approximate doubling time in YEARS?
1.46 years
If the doubling time of a population is 13 years, what is the annual growth rate?
5.4 %
Which type of species would make a poor indicator species? r or k selected?
R selected
What is an interacting group of organisms of different species that occupy the same geographic location called?
Community
The combination of biotic and abiotic factors interacting with one another is called…
an ecosystem
The total energy stored in this trophic level is highest due to the second law of thermodynamics
producer