Bio 101 exam

alternative RNA splicing

A process that allows a single gene to code for multiple proteins.

codon

A sequence of three nucleotides on an mRNA molecule that codes for a specific amino acid.

deoxyribose

The five-carbon sugar found in DNA nucleotides.

DNA ligase

An enzyme that joins DNA fragments together.

DNA polymerase

An enzyme that synthesizes new DNA strands during replication.

double helix

The twisted, ladder-like structure of DNA.

epigenetic

The study of changes in gene expression that are not caused by changes in the DNA sequence itself.

exon

A segment of a gene that codes for a protein.

gene expression

The process by which a gene's information is used to synthesize a functional product, like a protein.

genetic code

The set of rules by which information encoded in DNA or RNA is translated into proteins.

helicase

An enzyme that unwinds the DNA double helix during replication.

intron

A non–protein-coding intervening sequence that is spliced from mRNA during processing.

lagging strand

The DNA strand that is replicated discontinuously in short fragments.

leading strand

The DNA strand that is replicated continuously in the 5' to 3' direction.

mismatch repair

A cellular process that corrects errors in DNA replication.

mRNA

Messenger RNA; a molecule that carries the genetic code from DNA to the ribosome for protein synthesis.

mutation

A change in the DNA sequence.

nitrogenous base

A nitrogen-containing molecule that is a component of nucleotides.

nontemplate strand

The DNA strand that is not used as a template for transcription.

nucleotide excision repair

A DNA repair mechanism that removes damaged nucleotides.

Okazaki fragments

Short, newly synthesized DNA fragments on the lagging strand.

phosphate group

A functional group that is a component of nucleotides.

post-transcriptional

Referring to events that occur after transcription, such as RNA processing.

post-translational

Referring to events that occur after translation, such as protein folding and modification.

primer

A short strand of RNA that provides a starting point for DNA replication.

promoter

A sequence of DNA where transcription begins.

replication fork

The Y-shaped region where DNA is unwound during replication.

RNA polymerase

An enzyme that synthesizes RNA from a DNA template.

rRNA

Ribosomal RNA; a component of ribosomes.

semiconservative replication

The process of DNA replication in which each new DNA molecule consists of one original strand and one new strand.

splicing

The process of removing introns from pre-mRNA.

start codon

A three-nucleotide sequence that signals the beginning of translation.

stop codon

A three-nucleotide sequence that signals the end of translation.

telomerase

An enzyme that adds DNA to the ends of chromosomes.

telomere

A repetitive DNA sequence at the end of a chromosome that protects it from degradation.

template strand

The DNA strand that is used as a template for transcription.

transcription bubble

The region of DNA that is unwound and open during transcription.

tRNA

Transfer RNA; a molecule that brings amino acids to the ribosome during translation.

applied science |

The use of scientific knowledge to solve practical problems.

atom | The smallest unit of an element that retains the chemical properties of that element.

basic science | Scientific inquiry that aims to expand knowledge and understanding, often without a specific, immediate application.

biology | The study of living organisms and life processes.

biosphere | All the ecosystems on Earth, representing the parts of the planet where life exists.

cell | The basic structural and functional unit of life.

community | All the different populations of species living and interacting in a particular area.

control | The part of a scientific experiment that remains unchanged and is used as a baseline for comparison.

deductive reasoning | A form of logical thinking that uses a general principle or law to forecast specific results.

descriptive science | A type of science that involves observing, exploring, and documenting what is found in nature.

ecosystem | A community of living organisms and their interactions with the nonliving components of their environment.

eukaryote | An organism whose cells have a nucleus and other membrane-bound organelles.

evolution | The process of gradual change in a population's inherited traits over time.

falsifiable | A characteristic of a hypothesis that means it can be disproven by experimental results.

homeostasis | The ability of an organism to maintain stable internal conditions.

hypothesis | A suggested explanation for an observation that can be tested.

hypothesis-based science | A form of science that involves developing and testing specific hypotheses.

inductive reasoning | A form of logical thinking that uses specific observations to arrive at a general conclusion.

life science | A field of science that studies living organisms and life processes.

macromolecule | A large molecule, such as a carbohydrate, lipid, protein, or nucleic acid.

molecule | Two or more atoms joined by chemical bonds.

natural science | The study of the physical world, including biology, chemistry, and physics.

organ | A group of different tissues that work together to perform a specific function.

organ system | A group of organs that cooperate to perform a major body function.

organelle | A small, specialized structure within a cell that performs a specific function.

organism | An individual living being.

peer-reviewed article | A scientific article that has been evaluated by other experts in the same field before being published.

phylogenetic tree | A diagram that shows the evolutionary relationships among different species.

physical science | A field of science that studies non-living systems, such as chemistry and physics.

population | A group of individuals of the same species living in a particular area.

prokaryote | A single-celled organism that lacks a nucleus and other membrane-bound organelles.

science | A systematic process of gaining knowledge about the natural world through observation and experimentation.

scientific law | A statement that describes a phenomenon observed in nature and is universally accepted as true.

scientific method | The structured process of scientific inquiry, including observation, forming a hypothesis, experimentation, and drawing a conclusion.

scientific theory | A well-tested and widely accepted explanation for a broad range of observations.

tissue | A group of similar cells working together to perform a specific function.

variable | A factor in an experiment that can be changed or measured.

acid

A substance that donates hydrogen ions (H+) and lowers pH.

adhesion

The attraction between water molecules and other molecules.

amino acid

The monomer of a protein.

anion

A negatively charged ion.

atomic number

The number of protons in an element's nucleus.

base

A substance that accepts hydrogen ions (H+) and raises pH.

buffer

A solution that resists changes in pH.

carbohydrate

A macromolecule that provides energy and structural support.

cation

A positively charged ion.

cellulose

A polysaccharide that provides structural support in plant cell walls.

chemical bond

An attraction between atoms that holds them together in molecules.

chitin

A polysaccharide found in the exoskeletons of insects and fungi cell walls.

cohesion

The attraction between water molecules.

covalent bond

A strong chemical bond formed by the sharing of electrons between atoms.

denaturation

The process by which a protein loses its shape and function.

deoxyribonucleic acid (DNA)

A nucleic acid that contains the genetic instructions for an organism.

disaccharide

A carbohydrate made of two monosaccharides joined together.

electron

A negatively charged subatomic particle that orbits the nucleus.

electron transfer

The movement of an electron from one atom or molecule to another.

element

A pure substance that cannot be broken down into other substances by chemical means.

enzyme

A protein that acts as a catalyst to speed up chemical reactions.

evaporation

The process of a liquid turning into a gas.

fat

A type of lipid used for energy storage and insulation.

glycogen

A polysaccharide that stores glucose in animals.

hormone

A signaling molecule, often a protein or steroid, that regulates bodily processes.