Genetics and DNA Structure: Key Concepts and Scientists

DNA

Deoxyribonucleic acid, the molecule that carries genetic information in living organisms.

Heritable

Traits or characteristics that can be passed from parents to offspring through genes.

Prokaryotic DNA

The genetic material found in prokaryotic organisms, typically in a circular form and located in the nucleoid region.

Plasmids

Small, circular DNA molecules found in bacteria that can replicate independently of chromosomal DNA.

Eukaryotic DNA

The genetic material found in eukaryotic cells, organized into linear chromosomes within a nucleus.

Gregor Mendel

A scientist known as the father of genetics for his work on the inheritance of traits in pea plants.

Frederick Griffith

A bacteriologist who discovered the phenomenon of transformation in bacteria through his experiments with Streptococcus pneumoniae.

Avery, Macleod, McCarty

Researchers who demonstrated that DNA is the substance responsible for heredity in their experiments with Griffith's transformation principle.

Hershey and Chase

Scientists who conducted experiments using bacteriophages to confirm that DNA is the genetic material.

Nucleotides

The basic building blocks of DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenous base.

Pyrimidines

Nitrogenous bases in nucleotides that have a single-ring structure, including cytosine, thymine, and uracil.

Purines

Nitrogenous bases in nucleotides that have a double-ring structure, including adenine and guanine.

Erwin Chargaff

A biochemist known for Chargaff's rules, which state that in DNA, the amount of adenine equals thymine and the amount of cytosine equals guanine.

Chargaff's Rule

The principle that in a double-stranded DNA molecule, the amount of adenine equals thymine and the amount of cytosine equals guanine.

Template Strand

The strand of DNA that serves as a guide for the synthesis of a complementary strand during DNA replication.

Complementary Strand

The newly synthesized strand of DNA that pairs with the template strand according to base pairing rules.

Rosalind Franklin

A chemist whose X-ray diffraction images of DNA were critical in understanding its double-helix structure.

Watson and Crick

Scientists who proposed the double-helix model of DNA structure based on Franklin's work and other evidence.

Antiparallel Strands

The orientation of the two strands of DNA in a double helix, running in opposite directions.

Sugar-Phosphate Backbone

The structural framework of DNA and RNA, consisting of alternating sugar and phosphate groups.

Phosphodiester Bonds

Covalent bonds that link the sugar of one nucleotide to the phosphate of another, forming the backbone of DNA and RNA.