Biology Exam 1: Ch 1-3

An unsaturated fat that has been partially hydrogenated

• A lipid that is the major component of the cell membrane; are
• structurally similar to fats, but contain a phosphorus atom and have
• two, not three, fatty acid chains.

• A lipid important in regulating growth and development; include cholesterol and the steroid hormones testosterone and estrogen,
• and are all modifications of a basic structure of four interlinked rings of carbon atoms.

A long hydrocarbon (a chain of carbon–hydrogen molecules); fatty acids form the tail region of triglyceride fat molecules

A fat having three fatty acids linked to the glycerol molecule.

A fat in which each carbon in the hydrocarbon chain forming the tail region of the fat molecule is bound to two hydrogen atoms; are solid at room temperature.

Repelled by water, as, for example, non–polar molecules that tend to minimize contact with water.

A lipid similar in structure to fats but with only one long–chain fatty acid linked to the glycerol head of the molecule; because the fatty acid chain is highly non–polar, they are strongly hydrophobic

A small molecule that forms the head region of a triglyceride fat molecule.

• One of the sterols, lipids important in regulating growth and development; it is an important component of most cell membranes and is
• thus an essential molecule for living organisms.

Attracted to water, as, for example, polar molecules that readily form hydrogen bonds with water.

• A complex carbohydrate, indigestible by humans, that serves as the structural material for a huge variety of plant structures; it is the
• single most prevalent compound on earth.

A complex carbohydrate formed by the union of many simple sugars.

One of the four types of macromolecule; lipids are insoluble in water and greasy to the touch; they are important in energy storage and insulation (fats) and regulating growth and development

A complex carbohydrate, indigestible by humans, that forms the rigid outer skeleton of most insects and crustaceans.

A carbohydrate formed by the union of two simple sugars, such as sucrose (table sugar) and lactose (the sugar found in milk).

A complex polysaccharide carbohydrate consisting of a large number of glucose molecules linked in line; in plants, it is the primary form of energy storage,

• A complex carbohydrate consisting of stored glucose molecules linked to
• form a large web, which breaks down to release glucose when it is needed
• for energy.

The simplest carbohydrate and the building block of more complex carbohydrates; which cannot be broken down into other simple sugars, include glucose, fructose, and galactose.

One of the four types of macromolecule, containing mostly carbon, hydrogen, and oxygen; are the primary fuel for cellular activity and form much of the cell structure in all life forms.

A carbohydrate that contains multiple simple carbohydrates linked together.

A large molecule, characteristic of living organisms, made up of smaller building blocks or subunits; the four types are carbohydrates, lipids, proteins, and nucleic acids.

A logarithmic scale that measures the concentration of hydrogen ions (H+) in a solution, with decreasing values indicating increasing acidity; water, in which the concentration of hydrogen ions (H⁺) equals the concentration of hydroxyl ions (OH^â��), is pH =7, the midpoint of the scale.

Any fluid with a pH below 7.0, that is, with more H⁺ ions than OH^â�� ions

Any fluid with a pH above 7.0, that is, with more OH^â�� ions than H⁺ ions,

A chemical that can quickly absorb excess H⁺ ions in a solution (preventing it from becoming too acidic) or quickly release H⁺ ions to counteract increases in OH^â�� concentration,

A particle of matter than cannot be further subdivided without losing its essential properties.

A negatively charged particle that moves around the atomic nucleus,

The mass of an atom; the combined mass of the protons and neutrons in an atom (the weight of the electrons is negligible),

A substance that can not be broken down chemically into any other substances

The amount of matter in a given sample of a substance,

A group of atoms of the same or different elements held together by bonds

The sharing of two electrons between two atoms; for example, the most common form of oxygen is the O2 molecule, in which two electrons from each of the two atoms of oxygen are shared,

A type of weak chemical bond formed between the slightly positively charged hydrogen atoms of one molecule and the slightly negatively charged atoms of another (often oxygen or nitrogen atoms); important in building multi–atom molecules, such as complex proteins,

A positively charged particle in the atomic nucleus; it is identical with the nucleus of the hydrogen atom, which lacks a neutron, and has atomic number 1.

The central and most massive part of an atom, usually made up of two types of particles, protons and neutrons

The number of protons in the nucleus of an atom of a given element,

An electrically neutral particle in the atomic nucleus,

An atom that carries an electrical charge, positive or negative, because it has either gained or lost an electron or electrons from its normal, stable configuration.

A substance composed of atoms of different elements in specific ratios, held together by ionic bonds.

A bond created by the transfer of one or more electrons from one atom to another; the resulting atoms, now called ions, are charged oppositely and so attract each other to form a compound,

A strong bond formed when two atoms share electrons; the simplest example is the H2 molecule, in which each of the two atoms in the molecule shares its lone electron with the other atom.

A general, fact–based understanding of the basics of biology and other sciences,

The irrational belief that actions not related by logic to a course of events can influence an outcome,

Describing knowledge that is based on experience and observations that are rational, testable, and repeatable.

A body of knowledge based on observation, description, experimentation, and explanation of natural phenomena.

The ability to use scientific inquiry to think creatively about problems with a biological component; to communicate these thoughts to others; and to integrate these ideas into one's decision–making,

A process of examination and discovery of natural phenomena involving making observations, constructing hypotheses, testing predictions, experimenting, and drawing conclusions and revising them as necessary,

The study of living things.

An explanatory hypothesis for a natural phenomenon that is exceptionally well supported by the empirical data

An inactive substance used in controlled experiments to test the effectiveness of another substance

An experiment that makes it possible to determine decisively whether or not a hypothesis is correct,

A hypothesis that states the lack of relationship between two factors.

A proposed explanation for observed phenomena that can be tested.

In an experiment, the group of subjects exposed to a particular treatment;

In an experiment, the group of subjects not exposed to the treatment being studied but otherwise treated identically to the experimental group,

A frequently observed and poorly understood phenomenon in which people tend to respond positively to any treatment, whether placebo or active intervention,

An experimental design in which neither the subjects nor the experimenters know what treatment (if any) individual subjects are receiving,

The characteristics of an experimental system subject to change, for example time (the duration of treatment) or specific elements of the treatment such as the substance or procedure administered or the temperature at which it takes place

Describes a manner of choosing subjects and assigning them to groups on the basis of chance, that is, randomly,

Any experimental condition applied to the subjects of research,

An experimental design in which the subjects do not know what treatment (if any) they are receiving,

A set of analytical and mathematical tools designed to help us gain understanding of numerical data,

A direct relationship between variables, in which they increase (or decrease) together.

Observation of one or only a few instances,

Hypotheses and theories not supported by trustworthy and methodical scientific studies.

Two or more polypeptide chains bonded together; hemoglobin is an example of a protein molecule with this structure.

A nitrogen atom bonded to three hydrogen atoms,

The unique and complex three–dimensional shape formed by multiple twists of the secondary structure of the protein as amino acids come together and form hydrogen bonds or covalent sulfur–sulfur bonds.

One of the four types of macromolecule; constructed of unique combinations of 20 amino acids that result in unique structures and chemical behavior, the chief building blocks of all life.

The corkscrew–like twists or folds formed by hydrogen bonds between amino acids in a polypeptide chain,

A protein that initiates and assists a chemical reaction in a living organism.

Sequence of amino acids in a polypeptide chain,

One of 20 molecules built of an amino group, a carboxyl group and a unique side chain

The disruption of protein folding, in which secondary and tertiary structure are lost, caused by exposure to extreme conditions in the environment such as heat or extreme pH (that is, a strong acid or a strong base);  causes proteins to lose their function,

A carbon atom bonded to two oxygen atoms,

A bond in which the amino group of one amino acid is bonded to the carboxyl group of another; two amino acids so joined form a dipeptide, several amino acids so joined form a polypeptide.

One of the two types of nucleic acid, RNA serves as a middleman molecule, taking instructions for production of a given protein from DNA to another part of the cell, where it directs the construction of the protein from its constituent amino acids,

A molecule containing a phosphate group, a sugar molecule, and a nitrogen–containing molecule; are the individual units that together, in a unique sequence, constitute a nucleic acid,

One of the four types of macromolecule, nucleic acid stores genetic information in its unique sequence of the nucleotides that make it up; DNA and RNA are the two types of it

One of the two types of nucleic acid, DNA carries information about the production of particular proteins in the sequences of its nucleotide bases,

The spiraling ladder–like structure of DNA composed of two half–rung strands of nucleotides. The bases protruding from each strand meet in the center and bind to each other (via hydrogen bonds), holding the ladder together.

One of the four nitrogen–containing molecules attached to a sugar molecule in the sugar–phosphate backbone of DNA; the four are adenine (A), thymine (T), guanine (G), and cytosine (C);

A membrane–enclosed structure in eukaryotic cells that contains the organism's genetic information as linear strands of DNA in the form of chromosomes.

A cell bound by a plasma membrane enclosing the cell contents (cytoplasm, DNA, and ribosomes); there is no nucleus,

The organelle in plant and animal cells that converts the energy stored in food in the chemical bonds of carbohydrate, fat, and protein molecules into a form usable by the cell for all its functions and activities.

Granular bodies in the cytoplasm, released from their initial positions on the rough endoplasmic reticulum, that copy the information in segments of DNA to provide instruction for the construction of proteins,

A thin, hair–like projection that helps a prokaryote attach to surfaces.

The organelle in plant cells in which photosynthesis occurs.

Long, thin, whip–like projections from the cell body of a prokaryote that aid in cell movement through the medium in which the organism lives

The smallest unit of life that can function independently; a three–dimensional structure, surrounded by a membrane and, in the case of prokaryotes and most plants, a cell wall, in which many of the essential chemical reactions of the life of an organism take place.

A cell with a membrane–bound nucleus containing DNA, membrane–bound organelles, and internal structures organized into compartments,

The jelly–like fluid that fills the inside of the cell

An organism composed of eukaryotic cells.

A unifying and universally accepted theory in biology that holds that all living organisms are made up of one or more cells, and that all cells arise from other, pre–existing cells,

An organism consisting of a prokaryotic cell (all are one–celled organisms).

This theory proposes that certain ancestral eukaryotes engulfed other ancestral, energy-producing prokaryotes. Over time, the merged cells became more dependent on each other, and eventually the engulfed prokaryotes evolved into organelles, such as mitochondria or chloroplasts.

A complex, thin, two–layered membrane that encloses the cytoplasm of the cell, holding the contents in place and regulating what enters and leaves the cell; also called the cell membrane.

A rigid structure, outside the cell membrane, that protects and gives shape to the cell; found in many prokaryotes and plants,

The folding in of a membrane or layer of tissue so that an outer surface becomes an inner surface.

Specialized structures in the cytoplasm of eukaryotic cells with specific functions, such as the rough and smooth endoplasmic reticulum, Golgi apparatus, and mitochondria.

A protein that can penetrate the phospholipid bilayer of a cell's plasma membrane,

A small molecule that forms the head region of a triglyceride fat molecule.

Having an electrical charge,

The structure of the plasma membrane; two layers of phospholipids, arranged tail to tail (the tails are hydrophobic and so avoid contact with water), with the hydrophilic head regions facing the watery extracellular fluid and intracellular fluid,

Electrically uncharged,

A protein that initiates and assists a chemical reaction in a living organism; enzymatic proteins accelerate chemical reactions on the inside and outside surfaces of the plasma membrane.

Repelled by water, as, for example, non–polar molecules that tend to minimize contact with water.

A protein that resides primarily on the inner or outer surface of the phospholipid bilayer which constitutes the plasma membrane of the cell,

A transmembrane protein that provides a channel or passageway through which large or strongly charged molecules can pass;

A lipid that is the major component of the plasma membrane;

A protein in the plasma membrane that provides a "fingerprint" on the outside–facing surface of the cell, making it recognizable to other cells

A term that describes the structural nature of the plasma membrane, which is made up of several different types of molecules, many of which are not fixed in place but float, held in proper orientation by hydrophilic and hydrophobic forces,

One of the sterols, lipids important in regulating growth and development;

A protein in the plasma membrane that binds to specific chemicals in the cell's external environment to regulate processes within the cell

Attracted to water, as, for example, polar molecules that readily form hydrogen bonds with water.