Biology Chapters 1-3 Vocabulary

Vocabulary flashcards covering biological themes, chemical bonds, water properties, carbon isomers, and biological macromolecules from Chapters 1-3.

Biology

The natural science that studies life and living organisms.

Reductionism

An approach that organizes life into different levels of biological study, from single molecules to the entire planet.

Biosphere

All life on Earth and all the places where life exists.

Ecosystems

All living things and non-living things in a particular environment.

Communities

An array of organisms inhabiting a particular ecosystem.

Populations

All the individuals of a species living within a specified area.

Organisms

Individual living things.

Organs

A body part of an organism that carries out a specific function.

Tissues

A group of cells that work together to perform a specific function.

Cells

The fundamental unit that can perform all activities required for life.

Organelles

Various functional components inside cells.

Molecules

A chemical structure consisting of $2$ or more atoms.

Prokaryotic Cell

A type of cell lacking a nucleus or other membrane-enclosed organelles, which is smaller than a eukaryotic cell.

Eukaryotic Cell

A cell containing membrane-enclosed organelles, including a DNA-containing nucleus.

Genes

The units of inheritance that transmit genetic information from parents to offspring.

Gene Expression

The process of converting information from a gene to its cellular product.

Central Dogma

The directional process of genetic information transfer from DNA to RNA to Protein via transcription, translation, and protein folding, proposed by Francis Crick in $1958$.

Genome

An organism's entire set of genetic instructions.

Genomics

The study of sets of genes within and between species.

Amino Acid

Organic molecules that serve as the building blocks of proteins, containing an amino group and a carboxyl group.

Producers

Plants and other photosynthetic organisms that convert energy from sunlight into chemical energy.

Mutualism

A species interaction that is mutually beneficial, such as fish eating small parasites off turtles.

Predation / Parasitism

A species interaction in which $1$ species benefits and the other is harmed, such as a lion eating a zebra.

Competition

A species interaction in which both species are harmed, such as two plants competing for the same limited soil resource.

Commensalism

A species interaction where one species benefits and the other is unaffected, such as cattle egrets and buffalo.

Amensalism

A species interaction where one species is unaffected and another is harmed, such as an elephant walking on grass.

Evolution

The process of biological change in which species accumulate differences from their ancestors as they adapt to different environments over time.

Natural Selection

A process that results in the survival and reproductive success of individuals or groups best adjusted to their environment.

Hypothesis

An explanation based on observations and assumptions that leads to a testable prediction.

Elements

Substances that cannot be broken down or converted into other substances by chemical means.

Atoms

The smallest particle of an element that retains chemical properties.

Compound

A substance consisting of two or more elements in a fixed ratio.

Limiting Nutrient

The element in shortest supply relative to demands for plant growth.

Atomic Number

The number of protons in the nucleus of an element's atom.

Mass Number

The sum of protons plus neutrons in an atom's nucleus.

Isotopes

Forms of an element that differ in their number of neutrons.

Radioactive Isotopes

Isotopes in which the nucleus decays spontaneously, giving off particles and energy.

Potential Energy

The energy that matter has because of its location or structure.

Valence Shell

The outermost electron shell of an atom upon which its chemical behavior depends.

Covalent Bond

The sharing of a pair of valence electrons by two atoms.

Electronegativity

An atom's attraction for the electrons of a covalent bond.

Ions

Oppositely charged atoms resulting from the complete transfer of electrons.

Cation

A positively charged ion that has lost an electron.

Anion

A negatively charged ion that has gained an electron.

Ionic Bond

The chemical attraction between an anion and a cation.

Van der Waals Interactions

Weak interactions that occur when atoms and molecules are very close together due to asymmetric electron distribution.

Reactants

The starting molecules of a chemical reaction.

Products

The final molecules resulting from a chemical reaction.

Cohesion

The phenomenon in which water molecules stay close to each other due to hydrogen bonding.

Adhesion

The clinging of one substance to another, such as water to plant cell walls.

Surface Tension

The measure of how hard it is to break or stretch the surface of a liquid.

Solvent

The dissolving agent of a solution.

Solute

The substance that is dissolved in a solution.

Aqueous Solution

A solution in which water is the solvent.

Hydrophilic

A property describing a substance that has an affinity for water.

Hydrophobic

A property describing a substance that does not have an affinity for water, such as nonpolar oil molecules.

Macromolecules

Large, complex, and varied molecules found in living organisms, including carbohydrates, lipids, proteins, and nucleic acids.

Monomer

A small molecule that can chemically bind with other similar molecules to form a polymer.

Valence

The number of covalent bonds an atom can form, determined by the number of unpaired electrons in its outermost shell.

Isomers

Compounds with the same molecular formula and same number of atoms of the same elements, but with different structures and properties.

Structural Isomers

Isomers that differ in the covalent arrangement of their atoms.

Cis-Trans Isomers

Isomers that have different spatial arrangements of atoms around double bonds.

Enantiomers

Isomers that are mirror images of one another.

Functional Groups

Specific chemical groups attached to carbon skeletons that affect molecular function by participating directly in chemical reactions.

Adenosine Triphosphate (ATP)

An organic molecule consisting of adenosine attached to $3$ phosphate groups.

Polymers

Long molecules consisting of many similar building blocks called monomers.

Dehydration Reaction

A chemical reaction used to synthesize polymers by bonding $2$ monomers together with the loss of a water molecule.

Hydrolysis Reaction

A reaction meaning "water splitting" that breaks down polymers by adding water across a bond between $2$ monomers.

Monosaccharides

The simplest carbohydrates, serving as major nutrients for cells and raw materials for building molecules.

Disaccharide

A sugar molecule formed when a dehydration reaction joins two monosaccharides.

Glycosidic Linkage

A covalent bond formed between two monosaccharides by a dehydration reaction.

Polysaccharides

Carbohydrate polymers composed of many monosaccharides that perform storage and structural roles.

Starch

A plant storage polysaccharide consisting entirely of glucose monomers.

Glycogen

A storage polysaccharide stored mainly in liver and muscle cells of humans and other vertebrates.

Cellulose

A structural, straight, unbranched polymer of glucose that forms plant cell walls and is the most abundant organic compound on Earth.

Chitin

A structural carbohydrate found in arthropod exoskeletons and fungal cell walls that features a nitrogen-containing attachment on glucose monomers.

Saturated Fatty Acids

Fatty acids containing all carbon-to-carbon single bonds and maximum hydrogen atoms, which are solid at room temperature.

Unsaturated Fatty Acids

Fatty acids containing one or more double bonds and submaximal hydrogen atoms, which are liquid at room temperature.

Phospholipids

Lipids consisting of $2$ fatty acids, $1$ phosphate group, and glycerol, which form cell membrane bilayers.

Steroids

Lipids characterized by a carbon skeleton consisting of $4$ fused rings.

Proteins

Biologically functional molecules consisting of one or more polypeptides, which account for more than $50\%$ of cell dry mass.

Polypeptides

Unbranched polymers of amino acids linked together by peptide bonds.

Primary Structure

The unique, precise linear sequence of amino acids in a protein.

Secondary Structure

Coils and folds in a polypeptide chain resulting from hydrogen bonds in the polypeptide backbone.

Tertiary Structure

The overall three-dimensional shape of a polypeptide determined by interactions among side chains (R groups).

Quaternary Structure

The overall protein structure resulting from two or more individual polypeptides linked together.

Denaturation

The process in which a protein loses its native structure due to altered physical and chemical conditions.