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an organism that cannot synthesize its own food and is dependent on complex organic substances for nutrition.


does not rely on other living organisms, take in organic substances, on bottom of food chain


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


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


raw materials needed to make complex molecules and to increase cellular organization during growth


obtain energy from inorganic substances in the environment to make organic compounds


mainly bacteria that carry on chemosynthesis

Cell respiration

reactions that release the free energy in chemical compounds


autotrophs that produce food for themselves and other organisms to use


heterotrophs that consume plants and other organisms for food


Heterotrophs that use wastes, and dead plants and animals for food

Food Chain

a producer, one or more consumers and a decomposer


nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate


the living organisms in an ecosystem


biotic and abiotic components of a particular place


places where particular organisms live


the total of an organisms utilization of the biotic and abiotic resources of its enviroment


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.


left alone everything is left to disorder;

Synthesis Reactions

Less Disorder


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


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.


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


a molecule on which enzymes act


all of the chemical reactions and changes that take place in a cell or an organism


(entropy is going down) "building up reactions"


(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


removal of electrons from a molecule; lose 2 or more electrons

When protein is reduced

it gains electrons


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


Loses electrons oxidation


Gains electrons reduced

Autotrophs make

inorganic substances able for use

Autotrops make

their own food


absorbs nutrients


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)


the process of taking food into the digestive tract


a watery secretion containing digestive enzymes that begin chemical digestion.


a trapdoor like tissue that normally prevents food and liquids from entering the trachea


wavelike contradictions of the muscles of the esophagus, stomach, small and large intestine that move food though the digestive tract


undigested material that is eliminated from the body (poop)

Salivary amylase

enzyme in saliva that begins digestion of polysaccharides into shorter polysaccharides


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


Organisms can use light energy to synthesize organic compounds


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


Organisms that increase the total energy stored in organic compounds

Autotrophs and Heterotrophs

Organisms that require sunlight to survive


Organisms that make inorganic nutrients available for reuse


Organisms that make inorganic nutrients available for use


Organisms that use dead plants and animals for food.

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