Final Exam Study Guide: Ecosystems to Genomics

Biome

A region of Earth that experiences the same types of temperature and precipitation conditions, resulting in similar collections of plants and animals.

Trophic Cascade

A series of cause-and-effect events that occur after a change in an ecosystem.

Keystone Species

A species on which the other species in an ecosystem largely depend, such that if the keystone species were removed, the ecosystem would change drastically.

Molecule

Groups of atoms connected by chemical bonds.

Chemical Bonds

Connections formed by atoms sharing electrons (covalent bonds) or by interactions between positive and negative charges (ionic bonds).

Chemical Reaction

Occurs when the bonds of molecules break and atoms are rearranged to make new molecules.

Reactants

The molecules that are taken apart in a chemical reaction.

Products

The molecules that are produced in a chemical reaction.

Endergonic Reactions

Chemical reactions that require energy.

Exergonic Reactions

Chemical reactions that release energy.

Hydrolysis

Involves breaking down large molecules into smaller pieces.

Cell Respiration

A chemical reaction used by living things, where oxygen is used to release energy from glucose.

ATP

Adenosine triphosphate, an energy carrier molecule produced in exergonic reactions and used in endergonic reactions.

ATP Production Equation

6O2 + C6H12O6 → 6CO2 + 6H2O + Energy (36 ATP)

ATP Functions

Required for synthesizing large molecules, moving materials across cell membranes, and moving structures around in cells.

Aerobic Cell Respiration

Uses both glucose and oxygen, producing carbon dioxide and water as waste products.

Anaerobic Cell Respiration

Uses only glucose, producing ethanol or lactic acid as waste products.

Mitochondria

Organelles required for aerobic cell respiration.

Energy Conversion

Once energy is used, it is converted into heat and ultimately lost to the environment.

Recharging ATP

New energy can be used to 'recharge' the ATP molecules.

Food Chain

A linear sequence of organisms through which nutrients and energy pass as one organism eats another.

Food Web

A complex network of feeding relationships among various organisms in an ecosystem.

Biodiversity

The variety of life in the world or in a particular habitat or ecosystem.

Ecosystem Health

Maintained by biodiversity and species richness, which keeps the ecosystem healthy.

ATP Production in Anaerobic Respiration

Only 2 ATP are produced per glucose.

Aerobic Cell Respiration Inputs

Matter: Glucose, Oxygen.

Aerobic Cell Respiration Outputs

Matter: Carbon Dioxide, Water; Energy: 36 ATP.

Anaerobic Cell Respiration Inputs

Matter: Glucose.

Anaerobic Cell Respiration Outputs

Matter: Ethanol or Lactic Acid; Energy: 2 ATP.

Photosynthesis Reaction

6CO2 + 6H2O → C6H12O6 + 6O2.

Photosynthesis Definition

The chemical reaction that some living things (plants and algae) use to capture and store energy from the sun.

Energy Source for Photosynthesis

The energy required for this reaction comes from sunlight.

Chlorophyll Function

Absorbs red and blue-violet light and reflects green and yellow light.

Temperature Effect on Photosynthesis

Increased temperature increases the rate of photosynthesis up to a certain point.

Optimum Temperature

Above the optimum temperature, the rate of photosynthesis drops off because the enzymes responsible for photosynthesis start to denature.

Light Intensity Effect on Photosynthesis

Both the amount and the wavelength of light can limit the amount of photosynthesis that occurs.

Carbon Dioxide Concentration Effect

In general, the more carbon dioxide there is, the more photosynthesis occurs.

Carbon Pools

Carbon atoms form the main structure of all organic molecules.

Carbon Fluxes

Processes that move carbon from pool to pool.

Carbon Cycle

A model of how carbon atoms are moved around within ecosystems.

Plant Biomass

Carbon is contained within the molecules of glucose, stored in roots or special storage organs.

Animal Biomass

Carbon is contained within the molecules of animals, including proteins, fats, and carbohydrates.

Atmospheric CO2

Carbon is stored in the atmosphere in the form of carbon dioxide, which is 0.04% CO2, or more than 400 ppm.

Dissolved Carbon

Carbon is stored in water as dissolved CO2 or as carbonic acid.

Dead Organic Material

Carbon is stored in soil, in peat, and in limestone rocks.

Fossil Fuels

Carbon is stored in coal, oil, and natural gas.

Coal formation

Coal is formed when peat becomes compressed over time under layers of sediment.

Oil and natural gas formation

Oil and natural gas are formed in mud beneath lakes and seas, and become trapped when the mud turns to rock.

Photosynthesis (carbon fixation)

Producers convert CO2 from the atmosphere or the water into glucose through the process of photosynthesis.

Diffusion

CO2 can move between the atmosphere and water through the process of diffusion.

Assimilation

When consumers eat producers or other consumers, the carbon contained within plant or animal biomass is assimilated into the organic molecules of the organisms on the next trophic level.

Decomposition

When organisms die and decay, the carbon in their biomass becomes dead organic material in the soil.

Fossil fuel formation

Over time and under the right conditions, dead organic material can become limestone, coal, oil, or natural gas trapped within layers of rock.

Combustion

When plant biomass is burned, the carbon is released to the atmosphere in the form of CO2.

Combustion of fossil fuels

When fossil fuels are burned to create energy, the carbon is also released to the atmosphere in the form of CO2.

Volcanoes

Volcanoes can return carbon stored in rocks or fossil fuels to the atmosphere.

Monomer

A molecule that can be bonded to other identical molecules to form a polymer.

Polymer

A large molecule made of similar subunits bonded together.

Classes of biomolecules

There are 4 classes of biomolecules: carbohydrates, lipids, proteins, nucleic acids.

Amino Acids

The monomer of proteins.

Proteins

Proteins do most of the jobs within cells, including communication, movement, structures, chemical reactions, regulation.

Protein characteristics

Proteins contain C, H, O, N and sometimes P and/or S.

Protein uses

Proteins are used for communication, movement, structures, chemical reactions, and regulation within cells.

Protein structure

Amino acids link to form chains, chains fold into shapes that serve functions.

Protein

Biomolecule category that contains elements C, H, O, N, S, P and is made up of amino acids.

Carbohydrates

Biomolecule category that contains C, H, O and includes monosaccharides and polysaccharides.

Monosaccharide

The monomer of carbohydrates, also known as simple sugars, such as glucose.

Polysaccharide

The polymer of carbohydrates, also known as complex carbohydrates, such as starch or fiber.

Nucleic Acids

Biomolecule category that contains C, H, O, N, P and includes DNA and RNA.

Nucleotide

The monomer of nucleic acids, containing a nitrogenous base, a sugar, and a phosphate group.

Lipids

Biomolecule category that contains C, H, O and includes fatty acids, triglycerides, and phospholipids.

Fatty Acids

The monomer of lipids, which are long chains used for energy storage and insulation.

Triglycerides

A type of lipid polymer formed from glycerol and three fatty acids.

Phospholipids

A type of lipid that forms cell membranes, consisting of two fatty acids and a phosphate group.

Digestion Reaction

A reaction that breaks polymers down into monomers, releasing energy and is exergonic.

Synthesis Reaction

A reaction that connects monomers together to form polymers, requiring energy and is endergonic.

Metabolism

The total of all chemical reactions in the body, combining anabolism and catabolism.

Enzymes

Proteins that act as catalysts to speed up chemical reactions without being permanently changed.

Substrates

The reactants in enzyme-catalyzed reactions that bind to the enzyme's active site.

Active Site

The specific region on an enzyme where substrates bind to form the enzyme-substrate complex.

Enzyme-Substrate Complex

The intermediate formed when a substrate binds to an enzyme's active site.

Anabolism

The set of metabolic pathways that construct molecules from smaller units, requiring energy.

Catabolism

The set of metabolic pathways that break down molecules into smaller units, releasing energy.

C, H, O, N, S, P

Elements commonly found in biomolecules such as proteins, nucleic acids, carbohydrates, and lipids.

1 C : 1 O

The ratio of carbon atoms to oxygen in carbohydrates.

Variable R Group

The part of an amino acid that varies among different amino acids, determining their properties.

Hydroxyl (OH) Groups

Functional groups present in carbohydrates that contribute to their solubility and reactivity.

Carboxylic Acid Group (COO-)

A functional group present in amino acids that contributes to their acidic properties.

Denaturation

Under certain conditions, enzymes may denature when the enzyme changes shape so the active site no longer fits the substrate.

Enzyme denaturation causes

Enzymes may denature under high temperatures because the heat energy disrupts the bonds holding the enzyme together.

Enzyme denaturation in pH

Enzymes may denature in high or low pH conditions because the H+ ions or the OH- ions disrupt the bonds holding the enzymes together.

DNA structure

DNA is a polymer made up of many nucleotide monomers bonded together to form a 'ladder' and twisted into a double helix.

DNA backbone

The sugar and phosphate of each nucleotide bond together to form a strong 'backbone' of alternating sugar and phosphate.

Complementary base pairs

The nucleotides form complementary base pairs according to Chargaff's rule: A always pairs with T, C always pairs with G.

Hydrogen bonds in DNA

The base pairs are held together with hydrogen bonds, which are easily formed and broken so the two halves of DNA may be split and re-formed easily.

Nucleic acid

Long molecules built from monomers called nucleotides.

Ribose

Molecular formula = C5H10O5; simple sugar that is found in RNA.

Deoxyribose

Molecular Formula - C5H10O4; a form of ribose sugar that has lost one hydroxyl group (OH) and is the sugar that makes up DNA.

DNA replication

The DNA molecule is 'unzipped' by the enzyme helicase; new nucleotides are added to the exposed nucleotides by the enzyme DNA polymerase, which follows the base pairing rules.

DNA ligase

An enzyme that binds DNA fragments together.