General Chemistry, Water Properties, Biomolecules, and the Central Dogma

Vocabulary flashcards reviewing basic chemistry, atomic structure, water properties, biomolecules, and the central dogma of biology based on lecture material.

Controlled Experiment

An experiment designed to test a hypothesis in which all variables, except for the one being tested, are kept constant.

Hypothesis

A suggested, testable explanation formulated to account for a scientific observation.

Scientific Theory

A broad, proposed explanation for natural phenomena supported by extensive scientific reasoning, observations, and experimental evidence.

Cell Theory

The unifying biological principle stating that all living organisms are composed of cells, and all living cells come from pre-existing cells.

Bulk Elements

The chemical elements required by the body in large amounts, including carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus.

Atomic Number

The total number of protons contained within the nucleus of an atom of a particular element.

Atomic Weight

The total sum of protons and neutrons in the nucleus of a particular element.

Isotopes

Atoms of the same element that have identical atomic numbers but different atomic weights due to varying numbers of neutrons.

Half-Life

The constant amount of time required for exactly one half of the radioactive parent isotope atoms in a sample to undergo decay.

Oxidation

A chemical reaction process involving the loss of an electron from an atom or molecule.

Reduction

A chemical reaction process involving the gain of an electron by an atom or molecule.

Octet Rule

The chemical principle stating that atoms gain, lose, or share electrons to ensure their outermost shell is completely filled, thereby achieving stability.

Ionic Bond

A chemical bond formed by the electrostatic attraction between oppositely charged ions resulting from the complete transfer of electrons.

Covalent Bond

A chemical bond formed when two atoms share one or more pairs of valence electrons.

Polar Molecule

A molecule with an equal number of protons and electrons that possesses an unequal distribution of charge, creating a slightly positive end and a slightly negative end.

Hydrogen Bond

A weak attraction between the slightly positive hydrogen atom of one polar molecule and a slightly negative oxygen or nitrogen atom of another polar molecule.

Acid

A substance that breaks up in water to release hydrogen ions ($H^+$), creating a high hydrogen ion concentration.

Base

A substance that lowers hydrogen ion concentration by either taking up $H^+$ or releasing hydroxide ions ($OH^-$).

pH Scale

A numerical scale ranging from $0$ to $14$ used to measure acidity and alkalinity, where each unit change represents a $10\times$ difference in hydrogen ion concentration.

Hydrocarbon

An organic molecule consisting entirely of carbon and hydrogen atoms connected by energy-rich covalent bonds.

Functional Groups

Specific chemical groups attached to carbon skeletons that determine the structural properties and chemical reactivity of biological molecules.

Dehydration Synthesis

A chemical reaction that joins individual monomers together to form a polymer by removing a molecule of water.

Hydrolysis

A chemical reaction that breaks down polymers into smaller monomer subunits by adding a molecule of water to disrupt covalent bonds.

Monosaccharide

The simplest monomer unit of carbohydrates, serving as a primary energy source for cells (e.g., glucose, $C_6H_{12}O_6$).

Cellulose

A rigid structural polysaccharide in plant cell walls, commonly known as dietary fiber, that provides strength and support.

Saturated Fatty Acid

A fatty acid chain without carbon-carbon double bonds, forming straight chains that pack tightly together and are solid at room temperature.

Unsaturated Fatty Acid

A fatty acid chain containing one or more double bonds, resulting in a bent structure that prevents tight packing and remains liquid at room temperature.

Triglyceride

A lipid compound composed of three fatty acid chains attached to a glycerol backbone, serving as a major form of stored energy in animal cells.

Phospholipid

A membrane lipid made of glycerol, two hydrophobic fatty acid tails, and a hydrophilic negatively-charged phosphate group that forms bilayers in water.

Steroids

A class of nonpolar lipids composed of four fused carbon rings, including cholesterol and various hormones.

Nucleotide

The monomer subunit of nucleic acids, consisting of a five-carbon sugar, a phosphate group, and a nitrogenous base.

Deoxyribose

The five-carbon sugar found in DNA nucleotides, distinguished from ribose by missing an oxygen atom at the $2'$ carbon.

Gene

A specific segment of DNA that contains the nucleotide sequence instructions needed to synthesize a specific protein.

ATP (Adenosine-5'-triphosphate)

A modified nucleotide containing ribose, adenine, and three phosphate groups that functions as the primary energy currency of the cell.

Peptide Bond

The covalent bond formed between two amino acids during a dehydration reaction to build a polypeptide chain.

Primary Protein Structure

The linear sequence of amino acids in a polypeptide chain.

Enzymes

Proteins with specialized three-dimensional shapes that fit snugly around specific chemicals to facilitate and speed up chemical reactions.

Matter

Anything that has weight and takes up space, encompassing all solids, liquids, and gases in surroundings and living bodies.

Scientific Theory

A comprehensive explanation for a natural phenomenon that is supported by scientific reasoning and extensive evidence from a huge number of observations and experiments.

Hypothesis

A suggested, testable explanation formulated to account for a specific observation.

Cell Theory

The unifying biological principle stating that all living organisms are composed of cells, and all living cells arise from pre-existing cells.

Bulk Elements

Chemical elements required by the human body in large amounts, which include carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus.

Trace Elements

Chemical elements required by living organisms in small amounts.

Atom

The smallest complete unit of an element, consisting of a nucleus containing protons and neutrons surrounded by orbiting electrons.

Atomic Number

The total number of protons in the nucleus of an atom of a particular element.

Atomic Weight

The mass of an atom calculated as the sum of the number of protons and neutrons in its nucleus.

Isotopes

Atoms of the same element that have identical atomic numbers (protons) but different atomic weights due to varying numbers of neutrons.

Radioactive Isotopes

Unstable isotopes with nuclei that decompose over time, emitting energy or atomic fragments until reaching a stable form.

Half-Life

The constant amount of time required for one half of the radioactive atoms in a sample to decay.

Oxidation

The loss of an electron by an atom or molecule during a chemical reaction.

Reduction

The gain of an electron by an atom or molecule during a chemical reaction.

Octet Rule

The chemical principle that atoms gain, lose, or share electrons to completely fill their outermost shell with $8\text{ electrons}$ ($2$ for the first shell) to achieve stability.

Valence Electrons

The electrons occupying an atom's outermost shell that dictate its chemical reactivity and bonding behavior.

Ionic Bond

A chemical bond formed by the electrostatic attraction between oppositely charged ions created through electron transfer.

Covalent Bond

A chemical bond formed when two atoms share one or more pairs of valence electrons.

Catalysts

Substances that increase the rate of a chemical reaction without being consumed in the process.

Polarity

An unequal distribution of electrical charge within a molecule caused by unequal sharing of electrons between atoms.

Polar Covalent Bond

A covalent bond in which shared electrons spend more time near the atom with higher electronegativity, generating partial positive and negative charges.

Nonpolar Compound

A compound whose atoms share electrons equally or possess a symmetrical distribution of charge, leaving no net electrical poles.

Hydrocarbons

Molecules consisting solely of carbon and hydrogen atoms connected by energy-rich nonpolar covalent bonds.

Hydrogen Bond

A weak attraction between the slightly positive hydrogen atom of one polar molecule and the slightly negative oxygen or nitrogen atom of another polar molecule.

Solvent

The liquid component of a solution that dissolves solute particles; water is the primary biological solvent.

Solute

A substance (such as an ion or polar molecule) that dissolves in a solvent to produce a solution.

Hydrophilic

Descriptive of polar or ionic molecules that readily interact with and dissolve in water ("water-loving").

Hydrophobic

Descriptive of nonpolar molecules that do not mix with or dissolve in water ("water-fearing").

Cohesion

The property of water molecules tending to stick to one another due to intermolecular hydrogen bonding.

Adhesion

The property of water molecules sticking to different polar or charged surfaces via hydrogen bonding.

Surface Tension

A property of liquid water created by stronger cohesive hydrogen bonds between molecules at the surface, allowing it to resist external force.

Capillary Action

The movement of water upward through a narrow space or tube against gravity, driven by combined adhesion and cohesion.

Xylem

The system of microscopic vessels in plants through which water moves continuously upward from roots to leaves via capillary action and transpiration.

Specific Heat Capacity

The amount of energy required to raise the temperature of $1\text{ gram}$ of a substance by $1\,^\circ\text{C}$.

Acid

A substance that dissociates in water to release hydrogen ions ($H^+$), creating an $H^+$ concentration greater than pure water and a pH below $7$.

Base

A substance that takes up hydrogen ions ($H^+$) or releases hydroxide ions ($OH^-$) in water, resulting in a pH above $7$.

pH Scale

A logarithmic scale ranging from $0$ to $14$ used to measure the hydrogen ion ($H^+$) concentration and relative acidity or alkalinity of a solution.

Functional Groups

Specific polar or reactive clusters of atoms attached to carbon skeletons that participate in chemical reactions and confer distinct chemical properties to organic molecules.

Dehydration Synthesis

A chemical reaction that links monomer subunits together to construct polymers by removing a molecule of water ($H_2O$).

Hydrolysis

A chemical reaction that breaks the bond between adjacent monomers in a polymer through the addition of a water molecule ($H_2O$).

Monosaccharide

The monomeric simple sugar unit of a carbohydrate, represented by molecules such as glucose ($C_6H_{12}O_6$).

Disaccharide

A simple sugar molecule formed when two monosaccharides are linked together through dehydration synthesis.

Polysaccharide

A complex carbohydrate composed of long chains of monosaccharide subunits, utilized for energy storage or structural support.

Cellulose

A sturdy structural polysaccharide produced by plants to construct cell walls, serving as dietary fiber in human nutrition.

Lipids

Water-insoluble, nonpolar biological macromolecules composed mainly of carbon, hydrogen, and oxygen, including fats, phospholipids, and steroids.

Saturated Fatty Acid

A fatty acid chain with no double carbon-carbon bonds, forming straight structures that pack tightly and are solid at room temperature.

Unsaturated Fatty Acid

A fatty acid chain containing one or more double carbon-carbon bonds, creating bent chains that remain liquid at room temperature.

Triglyceride

A fat molecule formed by joining three fatty acid chains to a glycerol backbone, functioning as the primary form of stored energy in animal cells.

Phospholipid

A structural lipid consisting of a glycerol molecule bonded to two hydrophobic fatty acid tails and one negatively-charged hydrophilic phosphate head.

Steroid

A class of lipids characterized by a skeleton of four fused carbon rings, serving as membrane components and precursors to hormones.

Nucleotide

The monomer building block of nucleic acids, consisting of a five-carbon sugar, a phosphate group, and a nitrogenous base.

Gene

A specific segment of DNA whose sequence of nucleotides holds instructions for building a specific protein.

ATP (Adenosine Triphosphate)

A nucleotide derivative composed of adenine, ribose, and three phosphate groups that acts as the universal energy currency of the cell.

Amino Acid

One of $20$ different building block monomers of proteins, consisting of a central carbon bonded to an amino group, a carboxyl group, a hydrogen atom, and a variable $R\text{ group}$.

Polypeptide

A polymer chain consisting of multiple amino acids joined by covalent peptide bonds.

Peptide Bond

The covalent bond formed between the carboxyl group of one amino acid and the amino group of another during a dehydration reaction.

Primary Structure

The specific linear sequence of amino acids in a polypeptide chain.

Central Dogma of Biology

The core principle stating that genetic information flows from DNA to RNA via transcription, and from RNA to protein via translation.