By Itself, ________ Makes Up 70% of the Masses of All

question 18

Short Answer

By itself, ________ makes up 70% of the masses of all the planets combined.

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Definitions:

Genes

Units of heredity made up of DNA, acting as instructions to make molecules called proteins.

Twin Study

A study in which groups of monozygotic (identical) and dizygotic (fraternal) twins of the same sex are compared to each other and to other family members for similarity on a given trait.

Monozygotic Twins

Twins that are genetically identical because they were formed from a single fertilized egg that split into two, sharing 100% of their genes.

Dizygotic Twins

Also known as fraternal twins, these are siblings born at the same time who have developed from two different eggs fertilized by two different sperm, sharing about 50% of their DNA.