Ch. 5 Coping With Environmental Variation: Energy Flashcards
___ is the most basic requirement for all organisms.
Energy
Sunlight is ___ energy.
Radiant
___ energy is stored in the bonds of food molecules.
Chemical
___ energy is a form of potential energy.
Chemical
___ energy associated with movement of molecules is measured as temperature.
Kinetic
Autotrophs -
Organisms that assimilate energy from sunlight or from inorganic compounds
Photosynthesis -
Organisms assimilating energy from sunlight
Chemosynthesis -
Organisms assimilating energy from inorganic compounds
Heterotrophs -
Obtain their energy by consuming energy-rich organic compounds from other organisms
Detritivores -
Consume non-living organic matter
___ and ___ are heterotrophs that consume live hosts, but do not necessarily kill them.
Parasites and herbivores
___ are heterotrophs that capture and consume live prey animals.
Predators
Holoparasite -
Have no photosynthetic pigments and obtain all their energy from other plants
Hemiparasite -
Photosynthetic, but obtains nutrients, water, and some of its energy from the host plant
Some animals can become photosynthetic by acquiring or consuming photosynthetic organisms, or living in a close relationship called ___.
Symbiosis
Electrons are used to generate two high-energy compounds:
ATP and NADPH
The biochemical pathway used most commonly to fix CO2 is the ___ ___, catalyzed by several enzymes.
Calvin cycle
Important chemosynthesizers include the __ __.
Nitrifying bacteria
Photosynthesis has two major steps:
Light reaction
Dark reaction
Light harvesting is accomplished by ___ and accessory pigments.
Chlorophyll II
In plants, the thylakoid membrane is part of a specialized organelle called a ___.
Chloroplast
__ is the most abundant enzyme on earth.
Rubisco
Atmospheric O2 led to formation of an __ __ high in atmosphere that shields organisms from high-energy ultraviolet radiation.
Ozone layer
___ ___ ___ shows relationship between light levels and photosynthesis rate.
Light response curve
___ ___ ___ is light level at which CO2 uptake is just balanced by CO2 loss by respiration.
Light compensation point
Morphological changes are associated with acclimatization:
At high light levels, leaves are thicker and have more chloroplasts than leaves grown in low light
At low light levels, leaves are thinner and larger; increasing their surface area for greater light capture
Photoinhibition -
Excess energy generates toxic oxygen compounds that damage membranes
Carboxylase reaction
CO2 is taken up, sugars are synthesized, and O2 is released
Oxygenase reaction
O2 is taken up, leaving to breakdown of carbon compounds and release of CO2
__ results in a net loss of energy.
Photorespiration
Secondary metabolites
Herbivores tend to eat new growth with the highest nitrogen content and least harmful chemicals that protect plant
Plants that lack specialized biochemistry use the __ __ __.
C3 photosynthetic pathway
If atmospheric CO2 is low and ___ high, photosynthetic energy gain may not keep pace with photorespiratory energy loss.
Temperatures
The __ ___ __ reduces photorespiration.
C4 photosynthetic pathway
Most C4 plants have lower rates of transpiration at a given photosynthetic rate, known as ___ ___ ___.
Water use efficiency
C4 species are concentrated in ___, ___, and ___ latitudes.
Tropics, subtropics, and temperate latitudes
Some plants have a unique photosynthetic pathway that minimizes water loss -
Crassulacean acid metabolism (CAM)
Facultative CAM
Plants that can switch between C3 and CAM
Detritus -
Organic material derived from dead organisms
Fiber -
Includes compounds such as cellulose, but it is a poor energy source because most heterotrophs canning break it down
___ have the most energy per gram.
Fats
Absorptive heterotrophy -
Digest food outside their bodies and absorb nutrients
This ability of bacteria is exploited in ___.
Bioremediation
Variation in ___ ___ reflects adaptations that help to optimize food acquisition and minimize competition among groups of birds.
Bill morphology
Coprophagy -
Reingest their feces to enhance digestion
___ have a specialized stomach compartment in which large populations of bacteria facilitate the breakdown of cellulose.
Ruminants
Rumination -
Regurgitation of material from a fore stomach for additional chewing
___ can adjust their digestive morphological and produce different digestive enzymes.
Omnivores
