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111 Cards in this Set

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the spontaneous net movement of water molecules through a semipermeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.


the breakdown of glucose by enzymes, releasing energy and pyruvic acid.

what are the three main parts to cellular respiration?

Glycolysis, Kreb's cycle, and cellular respiration

What is energy?

the capacity to cause change

Kinetic energy

the energy of motion (the capacity to cause change through motion).

whats the conservation of energy?

the theory that energy can not be created nor destroyed.

What is potential energy?

The energy an object has because of its location or structure. At every moment an individual has a degree of potential energy.

What is the relationship between kinetic energy and potential energy?

It takes kinetic energy to form potential energy, which reverted back to kinetic energy at the moment of movement or impact. (A diver using kinetic energy to climb a ladder, at the top she has the highest potential energy, and therefore the most kinetic energy for that motion.)

Heat energy

The amount of kinetic energy contained in the movement of atoms and molecules in the body of matter. All energy conversions create some type of heat, just like hydrogen bonds. It is the most chaotic form of energy


A measure of the amount of disorder, or randomness, in a system. Entropy increases whenever there is energy is converted.

What is chemical energy?

Energy stored in chemical bonds of molecules, a form of potential energy. This arise from the arrangement of atoms and can be released during a chemical reaction.

How much energy is utilized in an engine when breaking down gasoline?

25%, while the rest is lost to heat

How much energy does the body utilize, and what does it do with the heat energy?

Roughly 34% is used, while the rest is used to maintain homeostasis, or our temperature equilibrium.


The amount of energy it takes to heat up one gram of water by 1 degree Celsius

What is more conventional to use for calories?

Kilocalories and Kilograms


Adenosine Triphosphate; Adenosine is an organic molecule, followed by a tail of three phosphate groups. Each phosphate is negatively charged. Having these three negatively charged phosphate groups creates potential energy.

What happens when ATP is used?

The end phosphate group is released, creating Adenosine diphosphate. ATP binds to the site, and releases energy when the movement is completed. The transfer of energy splits inorganic phosphate and ADP, and releases them from the binding site. A new ATP comes to the binding site to repeat the process.

What does hydrolyze mean?

breaks down a substance by reaction with water

When is ATP formed?

ATP is formed during cellular respiration when ADP and inorganic phosphate are reactants which produce ATP.


The total of the chemical reactions within an organism.


Proteins that speed up or facilitate the chemical reactions without being consumed by them.

What is activation energy?

The energy that is invested to start a chemical reaction.

why are enzymes important?

Enzymes help by reducing the amount of energy it takes to break the bonds of reactant molecules. Enzymes bind to the reactant molecules and puts them under stress.


The specific reactant on which an enzyme acts upon

active sites

A region of the enzyme that has the shape and chemistry that matches the substrate molecule.

Induced fit

When the active site changes shape slightly to embrace the substrate and catalyze the reaction.

How are enzymes named?

Usually they are named after their substrate

What are enzyme inhibitors?

Molecules that inhibit a metabolic reaction by binding to an enzyme and disrupting its function.

competitive inhibitors

Any compound which closely resembles the chemical structure and molecular geometry of the substrate. The inhibitor competes for the same active site as the substrate molecule. The inhibitor may interact with the enzyme at the active site, but no reaction takes place.

What are five benefits to membrane proteins?

Cell signaling: a binding site fits the shape of a chemical messenger. It may cause a change in the protein which relays the signal to the inside of the cell.

Attachment of the cytoskeleton and extracellular matrix: the protein helps the cell stay in shape and coordinate changes.

Enzymatic activity: Helps the substrate form products.

Transport: It may provide a channel for a substance to pass through.

Intercellular joining: proteins may link adjacent cells


The movement of molecules spreading out evenly into the available space from high concentration to low concentration.

Passive transport

When a substance passes through the plasma membrane/ diffusion without any energy being expended.

Based on your knowledge of the process of photosynthesis, would a plant under a red light survive better than a green light?

Yes, since green light is reflected by the chlorophyll

What is produced during the light reactions of photosynthesis?


The Calvin cycle constructs ___, an energy-rich molecule that a plant cell can then use to make glucose or other organic molecules


How do cells transport small, nonpolar, hydrophobic molecules, such as fatty acids or steroid hormones across the cell membrane?a) Such molecules diffuse freely.b) Via active transport.c) Via endocytosis.d) None of these choices.

Such molecules diffuse freely.

Which of the following characteristics affects the diffusion of a substance through the membrane?a) sizeb) degree of hydrophobicityc) concentrationd) all of these

a) sizeb) degree of hydrophobicityc) concentrationd) all of these

What would happen to red blood cells placed in an isotonic solution?a) Cells would lyse.b) Cells would shrink.c) Cells would maintain a constant volume.d) None of these.

Cells would maintain a constant volume

Redox reactions: (oxidation, reduction)

An oxidation-reduction reaction is any chemical reaction in which the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. OIL, RIG

facilitated diffusion

Still a form of diffusion. The transportation of substances via proteins, assisted transport. Binds substance to carrier protein, and the protein changes shape


A substance the dissolves in a solvent

What is hypotonic?

It is when the concentration gradient of a solute is not at equilibrium in comparison to the cell. The cell has a higher concentration of solutes than the exterior. Lysing can occur due to osmosis trying to solve the issue by diffusion


It is when the concentration gradient is higher on the exterior comparative to the cell. Shriveling can occur by the cell being drained of its water through osmosis.


When the solute is in equilibrium


The maintenance of constant osmotic pressure in the fluids of an organism by the control of water and salt concentrations.

Active Transport

Requires that a cell uses energy expends energy to move molecules across a membrane. Cellular energy (ATP) is used to drive a transport protein that pumps a solute against the concentration gradient.

This allows for cells to maintain internal concentrations of small solutes that may differ from the environmental concentrations.


The packaging of a particle by a cell engulfing it.


The vesicle that contains the engulfed particle.


The conversion of energy from sunlight to to chemical energy such as sugars and other organic molecules


Organisms that make all their own organic matter, including the four molecules of life from inorganic nutrients, such as carbon dioxide, water, and minerals from the soil. It is also known as a producer


Organisms that can not make organic molecules from inorganic ones. Therefore, they rely upon consuming another organism to obtain the nutrients they need. Its also known as a consumer

What does photosynthesis do?

chloroplasts within the cells utilize both 6 H2O and 6 CO2 with UV rays to produce glucose and 6 O2.

Aerobic process

A process by which the cell obtains ATP with including Oxygen in the process.

What is cellular respiration?

The aerobic harvesting of chemical energy from organic fuel molecules. Its byproducts are 6 carbon dioxide, 6 H2O, and about 32 ATP

What three stages are in cellular respiration?

Glycolysis, Kreb's cycle, and Oxidative Phosphorylation

What is Glycolysis?

Glucose is split into two molecules called pyruvic acid. Enzymes are located outside in the cytosol for this form of anaerobic respiration.

What are the steps for glycolysis?

Two three carbon molecules are formed by 2 ATP molecules which splits the 6 carbon glucose molecule. i(norganic)P(hosphate) reacts at the end of the 3 carbon molecule, along with another iP.Both three carbon molecules then donate high energy electrons to cation NAD, forming NADH.

After, ADP and the glucose with iP meet at an enzyme, transferring the iP and creating ATP. Since there is iP on both ends, that single 3 carbon molecule produces 2 ATP. Although gross production was 4, Net was 2 ATP, along with 2 pyruvic acid byproducts.

What is the Kreb's cycle?

Also known as the citric acid cycle, it completes the breakdown of glucose, or C6H1206. They are broken all the way down to CO2, and are released as a waste product. The enzymes used for the cycle are then dissolved in the fluid of the mitochondrion.

What are the steps of the kern cycle?

Pyruvic acid loses a C02, and forms acetic acid. Once again, electrons are stripped from the molecule, which are transferred to cation NAD, forming NADH.

Acetic acid then attaches to Coenzyme A, which escorts the acetic acid to the first reaction of the Kreb cycle. The Coenzyme A is then removed and reused in the process.

Acetic acid then joins a four carbon acceptor molecule to form a six carbon molecule called citric acid. For every acetic acid that joins, two CO2 will be a waste product.

Per acetic acid, one ATP will be formed, three NADH, and one FADH2. The acceptor molecule is the reused.

What is ETC/ Oxidative phosphorylation

Kreb’s and glycolysis both generate 2 ATP. They indirectly help generate more ATP, by reactions that transfer electrons from fuel molecules to a cation NAD. The electron transfer helps from a molecule NADH (H represents the involvement of a Hydrogen atom). NADH captured the released high energy electrons and brings them over for the final stage.

what is NAD?

Nicotinamide Adenine Dinucleotide

What are the steps to OxPh

Two electrons are passed from NADH to NADH dehydrogenase. Coupled with the transfer of the electrons is one hydrogen cation pumped through the protein to the inter membrane space for each electron.

This carries it to the Ubiquinone, a protein carrier, which transfers the two electrons to the cytochrome b-C1.

Each electron is then sent to Cytochrome C by an hydrogen ion which is pumped through cytochrome b-C1. Cytochrome C accepts only one electron at a time. In the cytochrome C oxidase, four electrons are required.

Within the cytochrome C oxidase, a molecular oxygen molecule and eight hydrogen atoms interact. Four electrons, four hydrogen atoms, and the oxygen molecule form two water molecules, while the other four hydrogen ions are pumped through the complex to through the inner membrane space. This creates a hydrogen ion gradient, which the ATP synthase uses as potential energy to create ATP. This gradient is formed by the inner mitochondrial membrane, spacing the matrix and the space between membranes.

Once three hydrogen cations have passed into the matrix space, there is enough energy to react ADP and inorganic phosphate. This results in about 28 ATP.

What can be converted into ATP?

Carbohydrates, some amino acids, and glycerols use all three of the cycles, Fatty acids and some amino acids use the krebs cycle


The anaerobic harvest of energy from food by some cells. Different pathways of fermentation lead to different end products, such as ethanol or lactic acid.

How long do muscle have to be subjected to strenuous, oxygen lacking work before they begin fermentation?

Muscles will begin to use fermentation after 15 seconds of anaerobic work

What happens in animal cells during fermentation?

Under strenuous situations where O2 can not be absorbed or used, the electrons that would typically transfer to cation NAD to the pyruvic acid, so the NAD can continue to take the electrons to produce ATP, creating Lactic acid.

Yeast fermentation

Once it has used ATP to separate the glucose and form the two 3 carbons, and transferred the two electrons to the two carbon molecules called ethyl alcohol. Two carbon dioxides are released as byproducts, which causes the bread to rise.

what are chloroplasts?

light absorbing organelles of the plant cell Leaves have the most chloroplasts, due to its surface area. It has about 500,000 chloroplasts per square millimeter.

How many chloroplasts are in a typical cell?


What is chlorophyll?

a pigment, light absorbing molecule within the chloroplast. It plays a central role in the absorption of UV rays, and converting it. Decreased temperatures result in the reduction of chlorophyll, which allows the carotenoids to be visible.

Why is chlorophyll green?

The light/wavelength predominantly reflected off of the chlorophyll/ chloroplast by extension is green, since blue, red, violet, and yellow are absorbed.

what is chlorophyll a?

A pigment that absorbs blue, violet, and red light

what is chlorophyll b?

A pigment that absorbs orange and blue light.

what are carotenoids?

Yellow/orange pigments that absorb blue-green light. They dissipate excess light energy that could damage the chlorophyll, preventing gene mutation.

What is the stoma (plural stomata)

the pores of the leaf that diffuse oxygen and CO2


the process of growing plants in sand, gravel, or liquid, with added nutrients but without soil.


the fluid within the chloroplast


One of a number of disk-shaped membranous sacs inside a chloroplast. It contains chlorophyll and the enzymes of the light reactions of photosynthesis. A stack is called a granum.


the inside of the thylakoid membrane.

Grana (singular- granum)

A stack of hollow disks formed by the thylakoid membrane in a chloroplast. Grana are the sites where light is trapped by chlorophyll and converted to chemical energy during the light reactions of photosynthesis.

What is the chemical formula for photosynthesis?

6 CO2 + 6 H2O → light energy/UV rays→ C6H12O6+ 6 O2

What is the chemical formula for Cellular respiration?

C6H1206 + 6 O2--> 6 CO2+ 6H2O+ ATP

What is a light reaction?

Chlorophyll in the thylakoid membranes absorb solar energy which is then converted into chemical energy in the forms of ATP and NADPH. The light reactions power the calvin cycle but do not directly produce the sugar.

What are the steps to light reaction?

Reaction center: where the primary electron acceptor and reaction center chlorophyll that transfers it are located.

When a photon hits a chlorophyll molecule that can absorb it, it creates resonance energy, which passes on from neighbor to neighbor until it arrives at the reaction center located in photosystem two. The chlorophyll releases an excited electron, which then goes to an Primary electron acceptor. One photon is needed to excite one electron in this chlorophyll. Once two electrons have been excited and transferred to plastoquinone, along with two protons from the lumen. The two electrons lost from the photosystem two are regained from the splitting of H2O(photolysis).

Two Hydrogen ions are released into the lumen, while molecular O2 is created, giving back the two lost electrons. Plastoquinone then transfers the two protons and electrons to the Cytochrome B6F complex. Upon docking, the two protons are released into the lumen, while the two electrons are coupled with two more hydrogen ions from the stroma which go into the lumen space, while the force carries the electrons to plastocyanin, a carrier, to the photosystem 1 complex. Protons again energize the chlorophyll, taking it to the Ferredoxin, which transfers the electrons to the Ferredoxin NADP reductase, or FNR. Once two electrons are transferred to FNR, they interact with NADP cation and a hydrogen ion, to make NADPH. This electron transport chain only helps form a gradient, which is utilized by the ATP synthase. It uses diffusion as a means to power ADP and iP to create ATP. It is similar to how water energizes in a dam.

What is NADPH?

Nicotinamide Adenine Dinucleotide Phosphate Hydrogenase, an electron carrier.

What is the calvin cycle?

The second of the two stages of photosynthesis, a cyclic series of chemical reactions that occur in the stroma of the chloroplast, using the carbon in CO2 and the ATP and NADPH produced by the light reactions to make the energy rich sugar molecule G3P, which is later used to produce glucose.

What are the steps for the calvin cycle?

Takes place in the stroma, carbon dioxide is fixed by an enzyme called Rubisco, which adds carbon dioxide to ribulose bisphosphate, or RuBP. These form two molecules.

O2 molecules are joined to six RuBP molecules, which forms six molecules that have six carbons. These fall apart spontaneously, which form 12 molecules of 3 carbons each, or PGA. Next, 12 ATP and NADPH are used to convert 12 PGA molecules to 12 G3P molecules. Each PGA molecule receives one phosphate from ATP, to form an intermediate molecule called 3 phosphoglyceraldehyde, or PGAL. PGAL then uses the high energy electrons from NADPH to convert them to Glyceraldehyde 3-phosphate, or G3P. Next, 2 of the G3P will leave the cycle to be converted into glucose or whatever the cell needs, organic wise. The remaining 10 G3P must be converted back to RuBP in order to replicate the process. An enzyme converts the remaining molecules into six five carbon compounds. 6 ATP is used to catalyze the conversion. This is a perpetual cycle as long as ATP and NADPH are present.


The distance across two crests of adjacent waves.

electromagnetic spectrum

the full range of radiation, from gamma rays to radio signals.


a fixed quantity of light. The shorter the wavelength, the higher the energy.

excited electron

The raised state, where the electron is highly unstable, which is heat energy, and almost immediately falls back into a ground state.

what is a photosystem?

A cluster of a few hundred pigments molecules, including chlorophyll a and b, and carotenoids


Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide (CO2) and release oxygen.

What are C3 plants?

C3 plants are the most common and the most efficient at photosynthesis in cool, wet climates.

C4 plants

C4 plants are most efficient at photosynthesis in hot, sunny climates.

carbon fixation

also known as сarbon assimilation refers to the conversion process of inorganic carbon (carbon dioxide) to organic compounds by living organisms. The most prominent example is photosynthesis, although chemosynthesis is another form of carbon fixation that can take place in the absence of sunlight.


The addition of a phosphate group (PO43−) to a molecule. Phosphorylation and its counterpart, dephosphorylation, turn many protein enzymes on and off, thereby altering their function and activity.

exergonic reaction

a reaction where energy is released. Because the reactants lose energy (G decreases), Gibbs free energy (ΔG) is negative under constant temperature and pressure. These reactions usually do not require energy to proceed, and therefore occur spontaneously.

Gibbs free energy

a thermodynamic quantity equal to the enthalpy (of a system or process) minus the product of the entropy and the absolute temperature.

If delta G is less than Zero, it's a spontaneous reaction. If a Delta G is more than zero, it's a nonspontaneous reaction. A increase in entropy or temperature will increase the spontaneous reaction, thereby decreasing the available energy.


Total energy of a system. The total energy of a system decreased or increased synonymously with Potential energy. It uses H as its symbol in a mathematical equation.


A measure of the amount of disorder, or randomness, in a system. Entropy increases whenever there is energy is converted. Its symbol is S.

Endergonic reaction

(an unfavorable reaction) is a chemical reaction in which the standard change in free energy is positive, and energy is absorbed.

The second law of thermodynamics

The second law of thermodynamics says that the entropy of any isolated system always increases. Isolated systems spontaneously evolve towards thermal equilibrium—the state of maximum entropy of the system. More simply put: the entropy of the universe (the ultimate isolated system) only increases and never decreases.

noncompetitive inhibitors

inhibitors that take a slot in the enzyme, but not directly where the substrate would bind at the active site.








are integral membrane proteins that serve as channels in the transfer of water, and in some cases, small solutes across the membrane.

tonicity of a solution

Determine whether cells regain same size, swells, or shrinks when a solution surrounds the cell, and the extent of which

what can pass through the semipermeable bilayer

Nonpolar, small, lipid soluble molecules can pass through


an integral membrane protein that is involved in the transport of many differing types of molecules across the cell membrane. The symporter works in the plasma membrane and molecules are transported across the cell membrane at the same time, and is, therefore, a type of cotransporter.