DNA & the Double Helix
The molecule located in the nucleus that contains the genetic code for all living organisms, shaped like a twisted ladder.
What is DNA (Deoxyribonucleic Acid)?
The observable physical traits or characteristics of an organism, such as eye colour or height.
What is a phenotype?
The process by which organisms with traits better suited to their environment are more likely to survive, reproduce, and pass on their genes.
What is natural selection?
The preserved remains, impressions, or traces of ancient organisms typically found embedded within sedimentary rock layers.
What are fossils?
The abbreviation for any plant or animal whose genetic material has been altered or modified using genetic engineering techniques.
What is a GMO (Genetically Modified Organism)?
A specific segment of DNA that codes for a particular protein or heritable characteristic.
What is a gene?
The unique combination of alleles an organism inherits for a specific gene (e.g., BB, Bb, or bb).
What is a genotype?
An environmental factor, such as a predator, disease, or climate change, that affects an organism’s chance of survival and drives evolution.
What is a selection pressure?
Features in different species that share a similar basic bone structure because they evolved from a common ancestor, like a whale's flipper and a human arm.
What are homologous structures?
An emerging gene-editing technology that allows scientists to act as "molecular scissors" to precisely cut, insert, or alter specific DNA sequences.
What is CRISPR (or CRISPR-Cas9)?
The tightly coiled, thread-like structures made of DNA and proteins; humans typically have 46 of these in their somatic cells.
What are chromosomes?
A grid diagram used by geneticists to model gene crosses and predict the probability of traits in offspring.
What is a Punnett square?
Any inherited structural, physiological, or behavioral feature that helps an organism survive in its specific environment.
What is an adaptation?
Biological features in different species that serve the same function but evolved independently, rather than from a shared ancestor.
What are Analogous stuructures?
The biotechnology process used to create an exact, genetically identical copy of a single gene, cell, or whole organism.
What is cloning?
The scientific term used to describe the entire, complete set of genetic material or DNA present in an organism.
What is a genome?
This type of allele will completely hide or mask the expression of a recessive allele when present in a heterozygous pair.
What is a dominant allele?
This occurs when a population is split by a physical barrier like a mountain range or ocean, preventing gene flow between the groups.
What is geographic isolation?
The geological law stating that in an undisturbed sequence of rocks, the oldest layers are at the bottom and the youngest are at the top.
What is the Law of Superposition?
Medical testing used to identify changes or mutations in a person's DNA to diagnose heritable diseases like cystic fibrosis or Huntington's disease.
What is genetic testing (or genetic screening)?
The Sequence of three consecutive DNA or RNA nucleotides that coresponds to a specific amino acid or signals the start or end of protein sythesis
What is a codon?
A diagrammatic family tree used in genetics to track the inheritance patterns of a specific trait or condition across multiple generations.
What is a pedigree chart (or pedigree)?
The evolutionary process by which new, distinct biological species arise from existing ones, often due to isolation and selection.
What is speciation?
Anatomical structures that have lost all or most of their original function through evolution, such as the human appendix or pelvic bones in whales.
What are vestigial structures?
Arguments regarding privacy of genetic data, potential discrimination by employers/insurers, and the concept of "designer babies" fall under this category of concern.
What are ethical (and social) implications?