Chapter 2 Flashcards
the ecosphere
- Lithosphere
- Hydrosphere (and cryosphere)
- Atmosphere
atmosphere includes
- Troposphere
- Stratosphere
- Mesosphere
- Thermosphere
energy
- Energy is the capacity to do work and is measured in calories (nutrition) or Joule (work required to produce one watt of power for one second (W⋅s) W=J/s
- Cal = 4.2 joules.
potential energy
is stored energy that is available for later use (e.g., gasoline)
kinetic energy
-Energy derived from an object’s motion and mass is known as kinetic energy (e.g., engine using gas)
low quality energy
- Most of the energy available for use is called low-quality energy.
- diffuse, dispersed at low temperatures, difficult to gather.
heat vs temp
- The total energy of all moving atoms is referred to as heat, a low-quality energy
- vs. temperature, a measure of average speed of molecules or atoms in a substance.
high quality energy
such as a hot fire, coal or gasoline, is easy to use, but the energy disperses quickly.
the first law of thermodynamics
- The first law is the law of conservation of energy
- energy can neither be created nor destroyed; it is merely changed from one form into another
- The total amount of energy in the universe is constant
the second law of thermodynamics
-The second law of thermodynamics (law of entropy) tells us that when energy is transformed from one form into another, there is always a decrease in the quality of usable energy; some energy is ‘lost’ as lower-quality, dispersed energy to the surrounding environment, often as heat
second law and organisms
- The second law of thermodynamics is important for organisms:
- because they must continuously expend energy to maintain themselves; whenever they use energy, some is lost
- because it tells us that energy cannot be recycled; it is constantly being degraded; the more we transform energy, the more is dispersed becoming less useful and lower quality
energy flow in ecological systems
- About 30% of the energy received is reflected by the atmosphere back into space.
- Of the remainder, about 50% provides heat to the Earth’s surface, 20% absorbed in the atmosphere, and less than 1% forms the basis for our ecological systems.
how plants produce O2
- Green pigments in plants, chlorophylls, absorb light energy from the sun.
- Plants combine carbon dioxide and water, using energy from the sun, into high-energy carbohydrates such as starches, cellulose, and sugars, during photosynthesis.
- Photosynthesis produces oxygen.
producers or autotrophs
Organisms with the ability to capture energy and manufacture matter are known as autotrophs, or producers.
heterotrophs or consumers
All other organisms are known as heterotrophs, or consumers.
two types of autotrophs
phototrophs and chemoautotrophs.
-Phototrophs get their energy from light, while chemoautotrophs obtain their energy from chemicals in the environment.
cellular respiration
- carbohydrates are broken down into inorganic molecules, carbon dioxide, and water.
- energy is released and can be used for many purposes by the organism.
aerobic organisms
must have access to oxygen for cellular respiration to take place, or they will die.
-Some species, anaerobic organisms (such as some bacteria), can survive even without oxygen.
food chains
- Each level of the food chain is called a trophic level.
- Herbivores eat producers and are the energy source for higher-level consumers, or carnivores.
- Omnivores, such as humans, raccoons, sea anemones, and cockroaches, can get their energy from multiple trophic levels.
consumers
- Primary Consumers: eating plants
- Secondary Consumers: eating herbivores
- Tertiary Consumers: eating animals that are secondary consumers or higher
food chain
Linked feeding series
trophic levels
An organism’s feeding status in a food web. Plants are at the producer level while animals are consumers
food webs
Network of food chains or feeding relationships
are all plants autotrophs
no Carnivorous pitcher plant gain their energy from ingesting the bodies of insects that trapped
detritus
These chains are based on dead organic material called detritus, which is high in potential energy but difficult for typical consumer organisms to digest.
decomposer food chains
play a key role in breaking down plant and animal material into products such as carbon dioxide, water, and inorganic forms of phosphorus and nitrogen and other elements.
detrital food chains
-Detrital food chains tend to dominate in forest ecosystems, and freshwater ecosystems.
grazing food chains
- Grazing food chains dominate in marine ecosystems.
- Producers are photosynthetic phytoplankton
- Zooplankton graze on the phytoplankton
