AP Biology - Unit 3, AP Biology Unit 4, AP Biology Unit 2, AP Biology Unit 1

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

ADP

adenosine diphosphate; molecule that ATP becomes when it gives up one of its three phosphate groups

free energy

Chemical energy available to do work

substrate level phosphorylation

the enzyme-mediated direct transfer of phosphate from another molecule (the substrate) to ADP

reduction

Gain of electrons by a chemical reactant; any reduction is accompanied by an oxidation.

oxidized

loses electrons

reduced

gains electrons

cellular respiration

The catabolic pathways by which electrons are removed from various molecules and passed through intermediate electron carriers to O2, generating H2O and releasing energy.

aerobic

Requiring molecular oxygen, O2

citric acid cycle

In cellular respiration, a set of chemical reactions whereby acetyl CoA is oxidized to carbon dioxide and hydrogen atoms are stored as NADH and FADH2. Also called the Krebs cycle.

pyruvate

Three-carbon compound that forms as an end product of glycolysis.

NADH

reduced electron carrier molecule formed during CR

Krebs cycle

another name for the citric acid cycle

acetyl CoA

molecule formed from the oxidation of pyruvate (2C compound)

FADH2

a reduced coenzyme similar to NADH, an electron carrier

anaerobic

Occurring without the use of molecular oxygen, O2.

fermentation

Speaking specifically about energy metabolism, the anaerobic degradation of a substance such as glucose to smaller molecules such as lactic acid or alcohol with the extraction of energy. (2) Speaking generally, metabolic processes that occur in the absence of O2.

lactic acid fermentations

Anaerobic series of reactions that convert glucose to lactic acid, in some bacteria and animal cells.

alcoholic fermentation

Anaerobic series of reactions that convert glucose to ethyl alcohol (ethanol) and carbon dioxide in some plants and yeast cells.

photosynthesis

photosynthesis: Metabolic processes carried out by green plants and cyanobacteria, by which visible light is trapped and the energy used to convert CO2 into organic compounds.

light reactions

The initial phase of photosynthesis, in which light energy is converted into chemical energy.

pigment

A substance that absorbs visible light.

chlorophyll

Any of several green pigments associated with chloroplasts or with certain bacterial membranes; responsible for trapping light energy for photosynthesis.

absorption spectrum

A graph of light absorption versus wavelength of light; shows how much light is absorbed at each wavelength.

action spectrum

A graph of a biological process versus light wavelength; shows which wavelengths are involved in the process.

photosystem

A light-harvesting complex in the thylakoid composed of pigments and proteins.

Calvin cycle

a series of enzyme-assisted chemical reactions that produces a three-carbon sugar from 3 CO2. Two 3C sugars will combine to form glucose

autotroph

An organism that is capable of living exclusively on inorganic materials, water, and an energy source other than the chemical bonds of organic compounds. Some autotrophs (photoautotrophs) use sunlight as their energy source. Others (chemoautotrophs) use oxidation of inorganic compounds.

heterotroph

An organism that requires preformed organic molecules as sources of energy and chemical building blocks.

kinetic energy

Energy associated with relative motion of objects.

thermal energy

Kinetic energy associated with the random movement of molecules or atoms. (heat)

potential energy

Stored energy.

entropy

A measure of disorder or randomness. Tends to increase in the universe.

free energy

Measures the portion of a system's energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell.

endergonic reaction

Reaction that absorbs free energy from its surroundings.

exergonic reaction

Reaction that proceeds with a net release of free energy.

catalyst

A chemical agent that speeds up a reaction without being consumed by the reaction.

enzyme

Protein that speeds up reactions. Typically end in "ase" (ex. Peroxidase, Lipase)

activation energy

The amount of energy needed to push the reactants over an energy barrier.

enzyme-substrate complex

When an enzyme binds to its substrate, it forms:

active site

A pocket or groove on the surface of the enzyme where a substrate can bind.

induced fit model

States that the enzyme and substrate undergo conformational changes to interact fully with one another (as opposed to "Lock & Key"

competitive inhibitors

Reduce the productivity of enzymes by blocking substrates from entering active sites.

noncompetitive inhibitors

Impede enzymatic reactions by binding to another part of the enzyme (other than the active site).

feedback inhibition/negative feedback

A metabolic pathway is switched off by the inhibitory binding of its end product to an enzyme that acts early in the pathway.

Chemical Energy

Potential energy trapped in molecular bonds.

Spontaneous Reaction

When a reaction doesn't require energy to proceed it is said to be this - doesn't mean it will be FAST.

Competitive inhibition

substance that resembles the normal substrate competes with the substrate for the active site

Noncompetitive inhibitor

a chemical that binds to an enzyme but not in the active site. This chemical will change the shape of the enzyme (reversible)

substrate

the substance an enzyme catalyzes, changes.

amylase

Enzyme that can break the bonds of starch to form the carbohydrate monomer, glucose.

Denature

Characteristic of proteins; a change in shape that stops the protein from functioning.

Allosteric

__________ regulation of enzyme occurs when a molecule binds to an enzyme changing the protein's shape

Catalyst

______ an agent that speeds up a chemical reaction without itself being permanently altered

Temperature

After looking at the shape of graph the enzyme activity of this enzymes is being regulated by what variable:

Substrate Concentration

After looking at the shape of graph the enzyme activity of this enzymes is being regulated by what variable:

Metabolism

The totality of an organism's chemical reaction

Catabolic pathway

Release energy by breaking down complex molecules into simpler ones i.e. Cellular respiration

Anabolic pathways

Consume energy to build complex molecules from simpler ones i.e. Amino acids making up proteins

breaks down molecules, negative ΔG

Catabolic

Energy storing, Positive ΔG

Endergonic

builds larger products, Positive ΔG

Anabolic

symbol G

Free energy

Adenine, ribose, phosphate group

ATP is composed of

Homeostasis

Maintaining a stable internal environment

Catalase

enzyme that breaks down hydrogen peroxide into water and oxygen.

chemiosmosis (oxidative phosphorylation)

the process of converting ADP to ATP by using the proton gradient to force protons (H+) through ATP synthase

ATP synthase

enzyme that catalyzes the reaction that adds a high-energy phosphate group to ADP to form ATP

NADPH

electron carrier that provides high-energy electrons for photosynthesis

purpose of light reactions

convert light energy into chemical energy in the form of ATP and NADPH

Purpose of Calvin Cycle

To make glucose from carbon dioxide using the enzyme Rubisco.

Purpose of the Krebs Cycle

Make energy carriers (NADH, FADH2)

purpose of glycolysis

break down of glucose into pyruvate

purpose of Fermentation

to regenerate NAD+ so glycolysis can continue

mitochondrial matrix

The compartment of the mitochondrion enclosed by the inner membrane and containing enzymes and substrates for the Krebs cycle.

Stroma (chloroplast structure)

fluid inside chloroplast where Calvin cycle occurs.

Endocrine system

Secretes hormones into blood from ductless glands that coordinate slower but longer-acting responses

Paracrine

Signals act on cells near the secreting cell

Local regulators

Chemical signals that travel over short distances due to diffusion

Autocrine

Signals act on the secreting cell itself (usually for apoptosis)

Pheromones

Chemical signals that are released from the body and are used to communicate with other individuals

Type I diabetes mellitus

An autoimmune disorder in which the immune system destroys pancreatic beta cells (usually develops while you're young)

Type II diabetes mellitus

Involves insulin deficiency or reduced response of target cells due to change in insulin receptors (due to being overweight and not exercising)

Hormone

A regulatory substance produced in an organism and transported in tissue fluids such as blood or sap to stimulate specific cells or tissues into action.

Negative Feedback

The diminution or counteraction of an effect by its own influence on the process giving rise to it, as when a high level of a particular hormone in the blood may inhibit further secretion of that hormone, or where the result of a certain action may inhibit further performance of that action.

Plant growth regulator

Organic compounds other than nutrients (like hormones that affect plant growth.

tropism

A growth response that results in the curvature of whole plant organs toward or away from stimuli owing to differential rates of cell elongation.

phototropism

Growth of a plant shoot toward or away from light.

action potential

A neural impulse; a brief electrical charge that travels down an axon.

anaphase

fourth stage of mitosis, in which the chromatids of each chromosome have separated and the daughter chromosomes are moving to the poles of the cell

binary fission

the type of cell division by which prokaryotes reproduce; each dividing daughter cell receives a copy of the single parental chromosome

cell cycle

an ordered sequence of events in the life of a eukaryotic cell, from its origin in the division of a parent cell until its own division into two; composed of M, G1, S, G2

cell cycle control system

a cyclically operating set of molecules in the cell that triggers and coordinates key events in the cell cycle

cell division

reproduction of a cell

cell plate

a double membrane across the midline of a dividing plant cell, between which the new cell wall form during cytokinesis

centromere

the centralized region joining two chromatids

centrosome

material present in the cytoplasm of all eukaryotic cells, important during cell division; the microtubule organizing center

checkpoint

a critical control point in the cell cycle where stop and go-ahead signals regulate the cycle

chromatin

complex of DNA and proteins that makes up a eukaryotic chromosome; when a cell is not diving it exists as a mass of very long, thin fibers that are not visible with a light microscope

chromosome

a threadlike, gene-carrying structure found in the nucleus; each consists of one very long DNA molecule and associated proteins, more condensed and coiled than chromatin