Chapter 3Chapter 3

GeneticsGeneticsMichael Hoerger

The BasicsThe Basics

• Nucleus: where most genetic material is stored, contains chromosomes

• Chromosomes: 46 (23 pairs), carry genes

• Genes: Segments on chromosomes, instruct cells how to make proteins

• DNA: basic molecules of genes

• See diagram: p. 60

ZygotesZygotes

• Zygote: single cell resulting from fertilization

• Monozygotic (identical) twins: originate from the same zygote, same DNA

• Dizygotic (fraternal) twins: originate from separate zygotes as a result of two ova available for fertilization, share about 50% of DNA (like any sibling)

Types of GenesTypes of Genes

• Structural Genes: code for proteins that help determine traits

• Regulatory Sequences: the “genetic switches” that influence when/where genes are expressed

Stephen Jay Gould VideoStephen Jay Gould Video

• What was Gould’s“great tragedy”?

• Questions?

Michael Hoerger

To cite this textbook:

• Berger, K. (2005). The developing person through the lifespan. New York: Worth.

To cite this lecture:

• Hoerger, M. (2007, January 17). Developmental Psychology: Genetics. Presented at a PSY 220 lecture at Central Michigan University.