Bio Q4 Final Vocabulary

DNA (Deoxyribonucleic Acid):

A molecule that carries genetic information. It is the blueprint for building and maintaining an organism, and is found in the cells of all living things.

Nucleotide:

The basic building block of DNA and RNA. Each nucleotide consists of a sugar, a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine in DNA).

Base Pair:

A pair of nitrogenous bases in a DNA molecule that are held together by hydrogen bonds. The base pairs in DNA are adenine (A) with thymine (T), and cytosine (C) with guanine (G).

Double-Helix:

The structure of DNA, consisting of two strands that twist around each other like a spiral staircase. This was first described by James Watson and Francis Crick.

Sugar-Phosphate Backbone:

The structural component of DNA (and RNA), consisting of alternating sugar (deoxyribose in DNA or ribose in RNA) and phosphate groups that form the "skeleton" of the molecule.

Gene:

A segment of DNA that contains instructions for making proteins or RNA. Genes determine traits and functions in living organisms.

Sequence (DNA or Amino Acid):

The order of nucleotides in DNA or the order of amino acids in a protein. This sequence determines the structure and function of the organism’s proteins.

Structure:

Refers to the specific arrangement or organization of components in biological molecules, cells, or organisms. The structure often dictates the function.

Function:

The role or purpose that a biological component (like a protein, gene, or organ) serves within an organism.

Protein:

A molecule made up of amino acids, essential for many functions in the body including catalyzing reactions (enzymes), building structures, and supporting immune function.

Transcription:

The process by which a segment of DNA is copied into RNA (specifically mRNA) in the nucleus.

Translation:

The process where mRNA is decoded to build a specific polypeptide (protein) at the ribosome in the cytoplasm.

Codon/Codon Wheel:

A three-nucleotide sequence in mRNA that codes for a specific amino acid. The codon wheel is a chart that shows the correspondence between codons and amino acids.

RNA (mRNA, tRNA, rRNA):

  • mRNA (messenger RNA): Carries the genetic code from the DNA to the ribosome.

  • tRNA (transfer RNA): Brings amino acids to the ribosome during protein synthesis.

  • rRNA (ribosomal RNA): Makes up the ribosome and helps with protein synthesis.

Ribosome:

The cellular machinery responsible for translating mRNA into proteins. It’s composed of rRNA and proteins.

Protein Synthesis:

The process by which cells make proteins, involving transcription and translation.

Amino Acid:

The building blocks of proteins. There are 20 different amino acids, each with its own properties.

Specialized Cell:

A cell that has developed a specific function, such as a nerve cell or muscle cell, often through differentiation.

Cell Specialization/Differentiation:

The process by which unspecialized cells (like stem cells) become specialized to perform a specific function in the body.

Mutation:

A change in the sequence of DNA, which can lead to changes in the structure and function of proteins.

Cell:

The basic unit of life. All living organisms are made up of cells.

Tissue:

A group of similar cells working together to perform a specific function (e.g., muscle tissue, nervous tissue).

Organ:

A group of tissues that work together to perform a specific function (e.g., heart, brain, liver).

Organ System:

A group of organs that work together to perform a major function in the body (e.g., the digestive system, respiratory system).

Organism:

An individual living being that can carry out all the basic functions of life, such as a human, plant, or bacterium.

Multicellular:

Organisms composed of many cells, such as humans, animals, and plants.

Unicellular:

Organisms composed of a single cell, such as bacteria and protists.

Nucleus:

A membrane-bound organelle in eukaryotic cells that contains the cell’s genetic material (DNA).

Cytoplasm:

The gel-like substance inside the cell where various cellular processes take place, excluding the nucleus.

Mitosis:

The process of cell division where a single eukaryotic cell divides to produce two genetically identical daughter cells.

Chromosome:

A long strand of DNA wrapped around proteins, containing many genes. Humans typically have 46 chromosomes.

Genetic Information:

The instructions encoded in DNA that guide the growth, development, and functioning of organisms.

Daughter Cells:

The two cells produced from the division of a single parent cell, such as in mitosis.

Stem Cell:

A cell that has the potential to develop into many different types of cells, essential for growth and tissue repair.

Gene Expression:

The process by which a gene's instructions are used to synthesize a functional gene product (such as a protein or RNA).

Gene Regulation:

The mechanisms that control the expression of genes, ensuring that the correct genes are active at the right time.

Homozygous:

An individual with two identical alleles for a particular gene (e.g., AA or aa).

Heterozygous:

An individual with two different alleles for a particular gene (e.g., Aa).

Gamete:

A reproductive cell (sperm or egg in animals) that carries half the genetic information of an organism.

Trait:

A characteristic or feature of an organism, such as eye color, height, or shape of a leaf.

Allele:

One of the different versions of a gene that can exist at a specific locus on a chromosome.

Genome:

The complete set of genetic material (DNA) in an organism, including all of its genes.

Zygote:

A fertilized egg cell, formed when a sperm cell fertilizes an egg cell.

Offspring:

The progeny or descendants of an organism.

Dominant:

An allele that expresses its trait even if only one copy is present (e.g., in a heterozygous individual, the dominant allele is expressed).

Recessive:

An allele whose trait is expressed only when two copies are present (homozygous condition).

Codominance:

A genetic scenario where both alleles in a heterozygous individual are fully expressed (e.g., AB blood type).

Incomplete Dominance:

A genetic scenario where the phenotype of a heterozygote is an intermediate blend of the two parental traits (e.g., red and white flowers making pink flowers).

Multiple Alleles:

A situation where more than two alleles exist for a gene, but an individual can only inherit two (e.g., blood type ABO system).

Punnett Square:

A diagram used to predict the genetic outcomes of a cross between two organisms.

True Breeding:

Organisms that, when bred, produce offspring identical to themselves for a given trait.

Heredity/Inheritance:

The passing of genetic material from parents to offspring.

Environmental Factor:

Any non-genetic influence on an organism’s traits or behavior, such as temperature, diet, or light.

Meiosis:

A type of cell division that reduces the chromosome number by half, creating gametes (sperm and egg).

Homologous Chromosomes:

Chromosomes that have the same genes in the same order but may carry different alleles for those genes.

Fertilization:

The process where sperm and egg cells combine to form a zygote.

Crossing Over:

The exchange of genetic material between homologous chromosomes during meiosis, increasing genetic diversity.

Variation:

Differences in traits among individuals within a population, often due to genetic differences.

Percentage/Proportion:

Mathematical terms for expressing part of a whole, often used in genetic calculations (e.g., genotype frequency).

Probability:

The likelihood that a particular event will occur, often used in genetics to predict inheritance patterns.

Distribution:

How traits or characteristics are spread out in a population.

Common Ancestry/Ancestor:

The concept that different species share a common ancestor from which they have evolved over time.

Biological Evolution:

The process by which species change over time through natural selection and other mechanisms.

Embryo:

An early stage of development in multicellular organisms after fertilization but before birth or hatching.

Analogous Structure:

Structures in different species that have a similar function but evolved independently (e.g., wings of a bat and a bird).

Homologous Structure:

Structures that have a similar origin in different species but may have different functions (e.g., the forelimbs of humans, cats, and whales).

Fossil Record:

The history of life as documented by fossils, providing evidence of past organisms and their evolution.

Anatomy/Anatomical Evidence:

The study of body structures to understand the relationships and evolution of species.

Vestigial Structure:

A structure in an organism that has lost its original function through evolution (e.g., human appendix, whale pelvis).

Molecular Evidence:

Evidence from genetic material (DNA, RNA, proteins) used to trace evolutionary relationships between species.

Biogeography:

The study of the distribution of species and ecosystems across the planet, often providing insights into evolution and ecological interactions.

Natural Selection:

The process by which individuals with traits that are better suited to their environment are more likely to survive and reproduce.

Sexual Reproduction:

A type of reproduction involving the fusion of two gametes (sperm and egg), resulting in offspring with genetic variation.

Resources:

Elements necessary for the survival of organisms, such as food, water, and shelter.

Competitive (Phenotypic) Advantage:

A trait that gives an individual better chances of survival and reproduction in its environment.

Generation:

A group of organisms born and living at the same time or the time span between the birth of parents and their offspring.

Species:

A group of organisms that can interbreed and produce fertile offspring.

Environmental Conditions:

Factors in the environment (e.g., temperature, humidity, food availability) that influence the survival of organisms.

Population:

A group of individuals of the same species living in a specific area.

Competition:

The struggle between organisms for limited resources like food, mates, and space.

Adaptation:

A characteristic or behavior that increases an organism's chances of survival and reproduction in a specific environment.

Climate Change:

Long-term changes in temperature, precipitation, and other climate patterns caused by natural and human factors.

Greenhouse Gas:

Gases in the Earth's atmosphere (e.g., carbon dioxide, methane) that trap heat and contribute to global warming.

Concentration:

The amount of a substance (e.g., greenhouse gases) in a given volume or area.

Ocean pH/Acidification:

The decrease in the pH of ocean water, often caused by excess carbon dioxide absorption, which can harm marine life.

Atmosphere:

The layer of gases surrounding Earth, essential for life and regulating temperature.

Geosphere:

The solid part of the Earth, including the crust, mantle, and core.

Biosphere:

All the living organisms on Earth, including plants, animals, and microorganisms.

Hydrosphere:

The water component of Earth, including oceans, rivers, lakes, and groundwater.

Temperature:

A measure of the warmth or coldness of an environment, affecting the survival of organisms.

Precipitation:

Any form of water (rain, snow, sleet, etc.) that falls from the atmosphere.

Sea Level:

The average level of the ocean's surface, used as a reference point for measuring elevation on land.

Glacier/Sea Ice:

Large masses of ice that form over land (glaciers) or float on the ocean (sea ice).

Weather/Climate:

  • Weather: Short-term atmospheric conditions.

  • Climate: Long-term weather patterns in a specific region.

Natural Hazard/Disaster:

Events such as earthquakes, floods, hurricanes, and wildfires that cause damage to the environment and human life.

Disturbance:

An event that disrupts an ecosystem, such as a fire, storm, or human activity.

Wildfire:

A large, uncontrolled fire that spreads rapidly, often in forests or grasslands.

Hurricane:

A powerful tropical storm with strong winds and heavy rain, typically occurring in warm ocean areas.

Volcanic Eruption:

The release of magma, gas, and ash from a volcano, which can have a significant impact on the environment.

Drought/Flood:

  • Drought: An extended period of deficient rainfall.

  • Flood: An overflow of water onto normally dry land.

Earthquake/Tsunami:

  • Earthquake: The shaking of the Earth's surface due to the movement of tectonic plates.

  • Tsunami: A large ocean wave caused by underwater earthquakes or volcanic eruptions.

Agriculture:

The practice of cultivating plants and raising animals for food, fiber, and other products.

Fossil Fuel:

Natural resources like coal, oil, and natural gas that are burned for energy.

Variable:

A factor that can change in an experiment or study, often influencing the results.

Projection/Prediction:

An estimate or forecast of future conditions based on current data and trends.

Uncertainty:

The degree of doubt or variability in predictions or measurements.

Climate Model:

A computer simulation used to predict future climate conditions based on current data and trends.