Discovery of DNA and Its Structure

These flashcards cover key concepts from the lecture on the discovery and structure of DNA, including historical figures, DNA composition, and the molecular structure.

What early practice did farmers use around 8000 BC to improve crops and livestock?

Selective breeding.

Who published the theory of evolution through natural selection?

Charles Darwin.

What did Gregor Mendel document in 1863?

Hereditary traits in garden peas.

Who are credited with accurately describing the double helix structure of DNA?

James Watson and Francis Crick.

What is the role of the sequence of three nucleotide bases in DNA?

Each corresponds to one of the 20 amino acids in protein production.

How similar is the DNA composition of humans to chimpanzees and gorillas?

99% similar.

What major project aimed to sequence the entire human genome?

The Human Genome Project.

What year was the Human Genome Project completed?

2002.

What is the sugar component of DNA called?

Deoxyribose.

What are the four nitrogenous bases found in DNA?

Adenine (A), Thymine (T), Guanine (G), Cytosine (C).

What is the difference between purines and pyrimidines?

Purines (A and G) are double-ringed structures, while pyrimidines (T and C) are single-ringed.

How are nucleotides linked together in DNA?

By phosphodiester bonds.

Describe Chargaff’s Law regarding base pairing in DNA.

The proportion of A to T is equal and the proportion of C to G is equal.

What occurs to thymine and adenine during complementary base pairing?

Thymine is always bonded to adenine.

What is the significance of the double helix structure of DNA?

It allows for the storage and replication of genetic information.

What type of bond holds the base pairs of nucleotides together?

Hydrogen bonds.

What is a key characteristic of the DNA strands?

They are antiparallel, meaning they run in opposite directions.