bio part 1

Characteristics of life

Order, evolutionary adaptation, response to the environment, regulation, energy processing, reproduction, growth & development.

Taxonomy

The classification system from most inclusive to least inclusive: domain, kingdom, phylum, class, order, family, genus, species.

Levels of organization

From most inclusive to least inclusive: biosphere, ecosystem, community, population, organism, organs/organ systems, tissues, cells, organelles, molecule.

Central Dogma

The process by which DNA transcribes into RNA, which then translates to proteins.

Adaptation

An inherited trait that enhances an individual’s ability to survive and reproduce in a particular environment.

Natural Selection

The survival of certain organisms with traits necessary for survival; conditions necessary include variation, overproduction, and heritability.

Theory

A potential reason for a hypothesis.

Prediction

A testable statement that supports the hypothesis in an if/then format.

Control Group

A group in an experiment held to every condition but the testable variable.

Experimental Group

A group in an experiment held to every condition including the testable variable.

Independent Variable

The variable manipulated or changed by the experimenter.

Dependent Variable

The variable measured during the experiment; the result of the independent variable.

Controlled Variables

Variables held constant throughout the experiment.

Placebo

A variable with no real effect designed to look like the actual variable being tested.

Inductive Reasoning

Used to come up with a general hypothesis.

Deductive Reasoning

Used to come up with a specific prediction.

Element

A pure substance that cannot be broken down into other types of substances; essential ones for life include carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.

Atom

The smallest unit of matter that retains the properties of a given element.

Protons

A subatomic particle with a positive charge.

Electrons

A subatomic particle with a negative charge.

Neutrons

A subatomic particle with a neutral charge.

Valence

The bonding capacity of an atom; the number of electrons required to complete the atom’s outermost shell.

Ionic Bond

An electrical attraction between ions (cation and anion), typically formed between a metal and a nonmetal.

Covalent Bond

A bond involving the sharing of electrons; strength increases from single to double bond, double to triple.

Non-polar Covalent Bond

A bond involving equal sharing of electrons; examples include O2, N2, CH4.

Polar Covalent Bond

A bond involving unequal sharing of electrons; example includes H2O.

Hydrogen Bond

An interaction between a hydrogen atom covalently linked to an electronegative atom and another electronegative atom.

Intermolecular Force

A force that exists between different molecules.

Intramolecular Force

A force that holds atoms together within a molecule.

Universal Solvent

A property of water; it dissolves more substances than any other liquid.

Adhesion

A property of water that allows it to stick to and interact with other surfaces.

Cohesion

A property of water that allows it to interact with itself, which contributes to surface tension.

High Specific Heat

A property of water that helps maintain temperature.

pH

A measure of hydrogen ion concentration in a solution.

pH Equation

pH = -log[H+]; [H+]*[OH-] = 10^-14.

Increases

If a pH of solution decreases, the H+ concentration of the solution __________.

Tetravalent

Describes carbon's chemical versatility as it can form up to 4 covalent bonds.

Functional Groups

The function of a biological molecule is determined by its functional groups and its overall 3D shape.

Isotope

A variant of an atom with the same number of protons but a different number of neutrons, resulting in a different atomic mass.

Hydroxyl

Molecular composition: -OH; compound name is alcohols.

Carbonyl

Molecular composition: >C=O; compound name is ketones or aldehydes.

Ketones

A carbonyl group that is located in the middle or inside of a molecule.

Aldehydes

A carbonyl group that is located at the end of a molecule.

Carboxyl

Molecular composition: -COOH; compound name is organic acids.

Amino

Molecular composition: -NH2; compound name is amines.

Sulfhydryl

Molecular composition: -SH; compound name is thiols.

Phosphate

Molecular composition: -OPO3^-2; compound name is organic phosphates.

Methyl

Molecular composition: -CH3; compound name is methylated compounds.

Isomers

Compounds that have the same molecular formula but different structures and properties.

Structural Isomers

Isomers that differ in the covalent arrangements of the atoms and/or the location of double bonds.

Cis-Trans Isomers

Isomers that have the same covalent partners but differ in spatial arrangement about a double bond.

Cis Isomers

Isomers where the covalent partners are on the same side of the molecule.

Trans Isomers

Isomers where the covalent partners are on opposite sides of the molecule.

Enantiomers

Isomers that are mirror images of each other, differing in spatial arrangement around an asymmetric carbon.

Monomer

A single repeating subunit.

Polymer

A long molecule consisting of many similar or identical subunits (monomers).

Dehydration Synthesis

The process in which a water molecule is lost when a covalent bond forms between two monomers.

Hydrolysis

The process in which water is added, breaking a covalent bond and incorporating H and O into the monomers.

Polysaccharide

A true polymer of carbohydrates, examples include starch, glycogen, cellulose, and chitin.

Monomer of Carbohydrates

Contains a hydroxyl group (OH) and a carboxyl group (-COOH); examples are glucose, fructose, galactose.

Glycosidic Linkage

The bond between carbohydrate monomers.

Maltose

A disaccharide formed from glucose + glucose.

Sucrose

A disaccharide formed from glucose + fructose.

Lactose

A disaccharide formed from glucose + galactose.

Starch

A polysaccharide functioning as storage in plants; an alpha polymer of glucose.

Glycogen

A polysaccharide functioning as storage in animals; an alpha polymer of glucose.

Cellulose

A polysaccharide providing structural support in plants; a beta polymer of glucose.

Chitin

A polysaccharide providing structural support in animals; a beta polymer of glucose.

Lipids

The only group of large biological molecules that is not a true polymer.

Components of Lipids

Contains glycerol and fatty acids.

Triacylglycerol

A lipid consisting of one glycerol and three fatty acids.

Saturated Fatty Acids

Fatty acids that do not contain double bonds.

Unsaturated Fatty Acids

Fatty acids that contain double bonds.

Phospholipids

A lipid that contains one glycerol, two fatty acids, and a phosphate group.

Steroids

A lipid consisting of four fused carbon rings with chemical groups attached.

Cholesterol

A component of membranes and a precursor for steroid hormones.

Ester Linkage

The bond connecting glycerol to fatty acids.

Polypeptides

The polymer of proteins.

Components of Proteins

Contains an amino group, a carboxyl group, and an R side chain.

Nonpolar Side Chain

Hydrophobic side chains made up mostly of carbon and hydrogen atoms.

Polar Side Chain

Hydrophilic side chains containing electronegative atoms such as OH, NH2, or SH.

Acidic Side Chain

Side chains that have negatively charged atoms.

Basic Side Chains

Side chains that have positively charged atoms.

Primary Structure

The sequence of amino acids in a protein.

Secondary Structure

The formation of alpha helices and beta sheets due to hydrogen bonding in the backbone.

Tertiary Structure

The overall three-dimensional structure of a protein.

Quaternary Structure

Proteins consisting of two or more polypeptide chains.

Peptide Bond

The bond formed between protein monomers.

Nucleotides

The monomer of nucleic acids.

Components of Nucleic Acids

Contains a nitrogenous base, a phosphate group, and a pentose sugar.

Deoxyribose

The sugar found in DNA.

DNA

Contains deoxyribose sugar, nitrogenous bases C, G, A, T, usually double-stranded, stores hereditary information.

Ribose

The sugar found in RNA.

RNA

Contains ribose sugar, nitrogenous bases C, G, A, U, usually single-stranded, needed for gene expression.

Light Microscopy

Uses light to view specimens and can view live cells.

Electron Microscopy

Uses beams of electrons to view specimens and cannot view live cells.

Scanning Electron Microscopy (SEM)

Shows the surface (3D) of a specimen.

Transmission Electron Microscopy

Shows the internal structure of a specimen.

Nitrogenous Bases

Cytosine, adenine, thymine, guanine.

Phosphodiester Bond

The bond forming between monomers in nucleic acids.