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Biology Chapter 2

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Heterotrophy
an organism that cannot synthesize its own food and is dependent on complex organic substances for nutrition.
Autotrophy
does not rely on other living organisms, take in organic substances, on bottom of food chain
Photosynthesis
process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches
Photoautotroph
organism that uses energy from sunlight to convert carbon dioxide and water to carbon compounds
Chemical Energy
energy stored in chemical bonds, energy stored in organic molecules
Free Energy
Energy available to do work in a chemical
Nutrients
raw materials needed to make complex molecules and to increase cellular organization during growth
Chemosynthesis
obtain energy from inorganic substances in the environment to make organic compounds
Chemoautotroh
mainly bacteria that carry on chemosynthesis
Cell respiration
reactions that release the free energy in chemical compounds
Producers
autotrophs that produce food for themselves and other organisms to use
Consumers
heterotrophs that consume plants and other organisms for food
Decomposers
Heterotrophs that use wastes, and dead plants and animals for food
Food Chain
a producer, one or more consumers and a decomposer
Abiotic
nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate
Biotic
the living organisms in an ecosystem
Ecosystem
biotic and abiotic components of a particular place
Habitats
places where particular organisms live
Niche
the total of an organisms utilization of the biotic and abiotic resources of its enviroment
Biosphere
all ecosystems of the earth
First Law of Thermodynamics
Energy cannot be created or destroyed, BUT IT CAN CHANGE FORM; Organisms cannot create their own energy, but must obtain it from an outside source
Law of Conservation of Energy:
The total energy of the universe is constant.
Entropy
left alone everything is left to disorder;
Synthesis Reactions
Less Disorder
Digestion
More Entropy
Avoid Entropy
By putting energy into the body
Second Law of Thermodynamics
systems tend to change in a way that increases the disorder of the system plus its surroundings
Enzymes
specialized proteins that lower the activation energy required to make a reaction proceed. Enzymes are not consumed; made up of single chain amino acids, the order of the amino acids determines the function of the proteins.
Catalysts
Chemicals that lower activation energy Enzymes are catalysts, but not all catalysts are enzymes.
Active Site
the portion (small area of the tertiary structure) of the enzyme that attaches to the substrate through weak chemical bonds
Substrate
a molecule on which enzymes act
Metabolism
all of the chemical reactions and changes that take place in a cell or an organism
Synthesis
(entropy is going down) "building up reactions"
Decomposition
(entropy is going up) "breaking down reactions" ; reactions in cells release the free energy that is stored in the structure of complex molecules
Reactions in cells release the free energy that is stored
in the structure of complex molecules
Oxidation
removal of electrons from a molecule; lose 2 or more electrons
When protein is reduced
it gains electrons
ATP
energy currency of the cells; has 3 phosphate groups; continually synthesized and broken down in cells
Enzymes are Catalysts
but not all Catalysts are Enzymes
LEO
Loses electrons oxidation
GER
Gains electrons reduced
Autotrophs make
inorganic substances able for use
Autotrops make
their own food
Fungi
absorbs nutrients
Digestion
the process that breaks down food
Physical Digestion
the breakdown of large pieces of food into smaller ones; increases surface area of food, making the chemical part of digestion easier
Chemical Digestion
the breakdown of complex food molecules into simpler ones. Enzymes lower activation energy
Extracellular Digestion
digestion that takes place outside the cells (most animals including humans)
Intracellular Digestion
digestion that takes place inside of the cells or inside of one celled organisms (in plants that digest food it makes itself)
Ingestion
the process of taking food into the digestive tract
Saliva
a watery secretion containing digestive enzymes that begin chemical digestion.
Epiglottis
a trapdoor like tissue that normally prevents food and liquids from entering the trachea
Peristalsis
wavelike contradictions of the muscles of the esophagus, stomach, small and large intestine that move food though the digestive tract
Feces
undigested material that is eliminated from the body (poop)
Salivary amylase
enzyme in saliva that begins digestion of polysaccharides into shorter polysaccharides
Autotrophs
organisms that release oxygen to the air during daylight hours
Autotrophs and Heterotrophs
Organisms that synthesize organic compounds during daylight hours
Autotrophs and Heterotrophs
Organisms that synthesize organic compounds during night-time hours
Autotrophs and Heterotrophs
Organisms that can synthesize energy-containing organic compounds
Autotrophs and Heterotrophs
Organisms that must use energy to synthesize organic compounds
Autotrophs
Organisms can use light energy to synthesize organic compounds
Heterotrophs
Organisms that use organic compounds as their only source of energy for synthesizing other organic compounds
Autotrophs and Heterotrophs
Organisms that can use the products of photosynthesis for synthesizing their organic compounds
Autotrophs
Organisms that increase the total energy stored in organic compounds
Autotrophs and Heterotrophs
Organisms that require sunlight to survive
Heterotrophs
Organisms that make inorganic nutrients available for reuse
Autotrophs
Organisms that make inorganic nutrients available for use
Heterotrophs
Organisms that use dead plants and animals for food.