Prokaryotic vs. Eukaryotic DNA & Human Genetic Diversity

Prokaryotes

Have a single chromosome loops that's 100% DNA, no nucleus, all inside cytoplasm, and reproduce through binary fission.

Eukaryotes

Have multiple chromosomes with DNA wrapped around histone proteins, DNA is very coiled and dense: 150,000x to the moon when unraveled, inside a nuclear lipid bilayer, and reproduction can be complex.

DNA

Genetic material for all life on earth, contains instructions for life.

Genetic Code

Instructions for functioning are contained in the order of the nucleotides in the DNA sequence.

Genetics

The study of DNA and inheritance.

Nucleotides

DNA is made up of 2 strands composed of nucleotides linked by covalent bonds.

Hydrogen Bonds

The 2 strands of DNA are linked by hydrogen bonds between nucleotide bases: A-T and C-G.

Gene Conversion

Maintaining DNA sequences over time; if the function of the protein is essential and unchanged, the structure (sequence) of the gene must be unchanged.

Sequence Homology

All cells from bacteria to archaea to humans have extremely high sequence homology in the small ribosomal sub-unit because they use the same mechanism to express DNA.

Skin Color

An adaptation to sunlight; darker skin provides protection from skin cancer, while lighter skin arose as a response to weaker sun in temperate regions to increase vitamin D absorption.

Hemoglobin Variants

Provide defense against infection by malaria; sickle cell anemia in people of African descent.

Sickle Cell Anemia

Caused by a mutation in red blood cells; you must have two mutated alleles (bb) and it helps protect against malaria.

Bb Genotype

Individuals that are Bb have no SCD symptoms and are protected from malaria in regions where malaria is prevalent.

Race

Does not have an inherent physical or biological meaning; any two humans are estimated to be only 0.6 percent different.

Ethnicity

A category of people who identify with each other, usually as an inherited status based on the society in which one lives.

Cultural Heritage

One of the shared aspects that define ethnic groups.

Symbolic Systems

Includes religion, mythology, and ritual as part of ethnic identity.

Gene Pool

Sometimes shared among ethnic groups due to shared ancestry.

Cuisine

Part of the shared identity of an ethnic group.

Dressing Style

Part of the shared identity of an ethnic group.

Art

Part of the shared identity of an ethnic group.