Chapter 2

What is DNA? What are genes and chromosomes? How many genes and how many chromosomes does a typical person have?

Define and give/recognize examples of genotype and phenotype.

What does it mean to say that a gene is dominant? Is recessive? Give examples of each.

Describe and give/recognize an example of incomplete dominance and polygenic inheritance.

How do chromosomes influence sex? What is the difference between sex and gender?

What is the “nature vs. nurture” debate? What is the final answer to this debate? Be able to recognize influences from genes, from the environment, and from a blend.

What do behavior geneticists study?

Define and give/recognize an example of reaction range.

Name and describe the three theories of genotype  –>  environment. Give/recognize an example of each. Explain how these theories cast new light on the old nature vs. nurture debate.

Describe the process of fertilization and conception.

Identify when implantation takes place.

Outline the major milestones of the embryonic period and identify when they take place.

Describe the major milestones of the fetal period and identify when viability occurs.

What are the three essentials of prenatal care? What are the recommendations for diet? For exercise? For teratogens?

Identify four major categories of teratogens. Which are more prevalent in developing countries and developed countries? Give/recognize specific examples within each. For each teratogen, describe how to avoid or reduce the impact.

What is Down syndrome? What causes it? How is mother’s/father’s age related to it?

Describe the three main techniques of prenatal diagnosis.

List the major causes of infertility for both men and women.

Describe current infertility treatments.

Key terms to define/understand

genome

sex chromosomes

monozygotic (MZ) twins

dizygotic (DZ) twins

gametes

ovum

follicle

zygote

germinal period

blastocyst

trophoblast

embryonic disk

ectoderm

mesoderm

endoderm

amnion

placenta

umbilical cord

embryonic period

gestation

ectoderm

mesoderm

endoderm

neural tube

neuron