Module Biology Lecture Flashcards

This set covers essential vocabulary from biology lectures, including the scientific method, basic chemistry, biomolecules, cell membrane transport, cell division, genetics, and viral cycles.

Scientific Method

A process of research with defined steps including experiments and careful observation.

Hypothesis

A suggested explanation that can be tested.

Theory

A working set of rules that define a body of knowledge; the underlying reasons "why" or a group of related ideas.

Law

A mathematical relationship or expression consistent with experimental data.

Order

Organized structures consisting of one or more cells.

Homeostasis

The maintenance of a relatively constant internal environment.

Protons

Particles found in the nucleus with a mass of about $1\,amu$ and a $+1$ charge; the number of these determines the element.

Neutrons

Particles in the center of an atom with no charge and about the same mass as protons.

Electron

The smallest of the three subatomic particles, found in constant motion in shells around the nucleus with a $-1$ charge.

Octet Rule

The tendency of atoms to prefer $8$ electrons in their outer shell to be "full" or stable.

Electronegativity

The affinity for or ability to attract electrons.

Polar Covalent Bond

A type of strong bond where electrons are shared unequally between elements.

Nonpolar Covalent Bond

A type of strong bond where electrons are shared equally between elements.

Ionic Bond

A chemical bond that forms between ions of opposite charges which attract each other.

Hydrogen Bond

A weak bond between partially positively charged hydrogen atoms and partially negatively charged elements or molecules.

Cohesion

The property of water molecules clinging together or interacting with other water molecules.

Adhesion

The property of water molecules clinging to surfaces or interacting with something else.

Acids

Substances with a higher concentration of hydrogen ions ($H^+$) and a pH closer to $0$.

Bases

Substances with a lower concentration of hydrogen ions ($H^+$) and a pH closer to $14$.

Monosaccharides

The monomers or simple sugars that serve as the building blocks of all carbohydrates.

Lipids

Molecules made of a glycerol and three fatty acid tails used for insulation, protection, and stored energy.

Proteins

Biomolecules used to repair and build structures, made of amino acids.

Nucleic Acids

Biomolecules like DNA and RNA that provide instructions to build proteins, composed of nucleotides.

Nucleotide

The building block of nucleic acids consisting of a pentose sugar, a nitrogen base, and a phosphate group.

Selective Permeability

The property of a cell membrane that allows it to choose what passes through while blocking others.

Osmosis

The diffusion of water molecules traveling across a semipermeable membrane.

Hypertonic

A solution that is more concentrated with solutes than the solution it is being compared to.

Hypotonic

A solution that is less concentrated with solutes than the solution it is being compared to.

Prokaryotic Cell

A simple, single-celled organism that lacks a nucleus or any other membrane-bound organelle.

Eukaryotic Cell

A cell containing a membrane-bound nucleus and other membrane-bound compartments called organelles.

Interphase

The phase of the cell cycle where DNA replication happens before mitosis begins.

Apoptosis

Programmed cell death.

Mutagen

A physical or chemical agent that changes DNA and causes a mutation.

Carcinogen

Any agent that causes cancer, which may be a mutagen or an agent that disrupts cellular metabolism.

Diploid ($2n$)

Having two complete sets of chromosomes ($46$ total in humans).

Haploid ($n$)

Having one set of chromosomes ($23$ in humans), typical of gametes like sperm and egg.

Crossing Over

The process in Prophase I of meiosis where homologous chromosomes trade pieces while close together.

Nondisjunction

An error in meiosis where chromosomes do not separate correctly.

Negative Feedback

A regulatory mechanism where the product of a process stops or inhibits the process to maintain balance.

Transcription

The process where DNA is used as a template to create mRNA.

Translation

The synthesis of a protein from an mRNA template using tRNA to carry amino acids.

Codon

A sequence of three bases in mRNA that is read in pairs or triplets to determine a specific amino acid.

Capsid

The protein shell or coat that encloses the genetic material of a virus.

Lytic Cycle

A viral replication cycle where the virus attaches to a host, replicates rapidly, and causes the host cell to burst.

Lysogenic Cycle

A viral cycle where genetic material is hidden in the host genome and replicates normally with the cell; it may later trigger the lytic cycle.

Genetic Drift

A change in allele frequency due to chance factors.

Evolution

A change in the gene pool of a population over time.

Natural Selection

The process that results in organisms that are better adapted to their local environment.

Speciation

The formation of new and distinct species in the course of evolution.