Intro to Genetics and Biotechnology

A comprehensive set of Q&A flashcards covering key genetics concepts, model organisms, and major historical milestones from the lecture notes.

What is genetics?

The science of heredity—the study of how traits are passed from one generation to the next.

What are the four major sub-disciplines of genetics?

Transmission genetics (pedigree & Punnett squares); Molecular genetics (gene expression and DNA technologies); Quantitative genetics (polygenic traits); Population genetics (gene frequency in a population).

What makes an organism a good model for studying genetics?

A well-known genetic history, quick reproduction, large number of offspring, ease of handling, and genetic variation among individuals.

Name the six model organisms commonly used in genetics.

Escherichia coli (E. coli); Baker’s yeast; Drosophila melanogaster (fruit fly); Mustard plant; Mus musculus (house mouse); Caenorhabditis elegans (nematode worm).

Who proposed natural selection and the survival of the fittest in 1859?

Charles Darwin.

What did Gregor Mendel discover about inheritance in peas?

Traits can be recessive or dominant in inheritance.

What did Friedrich Miescher isolate in 1869 and what did it become understood as?

DNA from fish sperm and pus; initially named nuclein, later nucleic acid, and finally DNA.

What term did Walther Flemming coin related to cell division?

Chromatin; he also described mitosis and the “asters” (centrosomes and centrioles).

What did Hugo de Vries propose in 1900 about inheritance?

Inheritance comes in particles (pangenes), now known as genes; he rediscovered Mendel's work.

What disease did Archibald Garrod study and what did he conclude?

Alkaptonuria; it is inherited in a recessive pattern due to a mutation in a gene encoding an enzyme.

What does the chromosome theory of heredity state and who proposed it?

Genes are on chromosomes; their segregation is due to chromosome segregation; proposed by Walter Sutton and Theodor Boveri.

What terms did Wilhelm Johannsen introduce in 1909 and what is their relation?

Phenotype and genotype; he also shortened 'pangene' to 'gene.'

What was Thomas Hunt Morgan's key finding in Drosophila?

Genes are carried on chromosomes; some traits are sex-linked; crossing over occurs between chromosomes.

What was Griffith's transforming principle?

DNA; transformation of a harmless strain into a virulent one via uptake of DNA.

What is the 'one gene, one enzyme' hypothesis and who proposed it?

A gene encodes a specific enzyme; proposed by Beadle and Tatum.

What did Avery, MacLeod and McCarty demonstrate in 1943?

DNA is the genetic material and causes transformation.

What is Barbara McClintock known for?

Transposition ('jumping genes'), maize genetics, genetic mapping, and regulation of gene expression.

What did Hershey and Chase demonstrate in 1952?

DNA is the genetic material; bacteriophage experiments showed DNA, not protein, is injected into bacteria.

What were Rosalind Franklin's key contribution(s)?

X-ray crystallography images suggesting DNA's structure; evidence for the helix and base-pair spacing.

What did James Watson and Francis Crick discover in 1953?

DNA has a double-helix structure and proposed mechanisms for replication and protein synthesis.

What did Meselson and Stahl demonstrate in 1958?

DNA replication is semiconservative; heavy nitrogen experiments showed one heavy and one light strand after replication.

What did Khorana, Holley, and Nirenberg contribute to the genetic code?

First to use the letters A, U, G, and C for the genetic code and to determine codon–amino acid relationships.

Who discovered restriction enzymes and when?

Arber, Smith and Nathans (1960s–1970s).

Who is regarded as the father of genetic engineering and what did he do?

Paul Berg; pioneered recombinant DNA technology and created molecules with DNA from two different species.

What did Fred Sanger contribute to biology?

Determined amino acid sequence of proteins and developed the Sanger sequencing method for nucleic acids.

What was the 1980s contribution of Botstein, Davis, Skolnick and White?

Proposed that Restriction Fragment-Length Polymorphisms (RFLPs) can be used for mapping the human genome; used electrophoresis to identify diseases.

Who invented PCR and when?

Kary Mullis (1983).

What project did Francis Collins lead and what were its achievements?

The Human Genome Project; mapped the human genome and identified genes behind diseases like cystic fibrosis, Type 2 diabetes, and Huntington’s disease.

What discovery did Fire and Mello make in 1998?

RNA interference (RNAi); RNA can block messenger RNA and silence genes.

What is CRISPR-Cas9 and who led its discovery?

CRISPR-Cas9 gene editing technology; Doudna and Charpentier (2012).