SSHS Biology Genetics and Evolution Unit Topic 1
Evolution and Genetics
Mendelian, Human,
Molecular Genetics
Topical Understanding
A gene is a portion of DNA on a chromosome that codes for a specific protein. Individuals possess two copies of a gene – one inherited from each parent. The genes that are passed down from one generation to the next determine the characteristics of living things. The principles of probability can be used to predict the outcomes of genetic crosses. Meiosis is a highly regulated process that produces gametes (sex cells) containing half the number of chromosomes of a regular cell, so the resulting zygote will have the same number of chromosomes as the parents.
Human genetic traits can be traced through pedigrees. Human genetic disorders can be caused by single genes or chromosomes.
Genes are composed of specifically ordered DNA molecules. The structure of DNA allows it to be precisely replicated. The DNA code of a gene is used to produce a specific protein in the process of protein synthesis.
Essential/Probing Questions
· How do geneticists use Mendel’s principles and probability to predict the outcome of genetic crosses?
· How does meiosis maintain the continuity of species? What are the similarities and differences between mitosis and meiosis?
· How are genetic diseases different than communicable diseases?
· What is the relationship between DNA, genes, and chromosomes?
· How does the structure of DNA allow it to replicate?
· How do the processes of transcription and translation show the relationship between genotype and phenotype?
Areas of Focus
q Mendelian Genetics
q Human Genetics
q Molecular Genetics
Knowledge and Skills
q Mendelian Genetics
o Gregor Mendel
o The Principle of Dominance
§ Genes, alleles, traits, and hybrids
o The Principle of Segregation
§ P, F1, and F2 generations
§ Gametes
· Probability and Punnett Squares
o Homozygous vs. Heterozygous
o Genotype vs. Phenotype
o Single trait crosses
o Multiple trait crosses
o The Principle of Independent Assortment
· Non-Mendelian Genetics
o Incomplete dominance
o Codominance
o Multiple alleles
o Polygenic traits
o Genes and the environment
· Meiosis
o Homologous pairs
o Meiosis I
o Meiosis II
o Human gamete formation
· Gene linkage and Chromosome Maps
q Human Genetics
· Human Heredity
o Human Chromosomes
o Pedigrees
o Sex-linked traits
· Human Genetic Disorders
q Molecular Genetics
· DNA and Genetics
o Griffith, Avery, and Hershey-Chase
o DNA structure
· Chromosomes and DNA Replication
o DNA and chromosome structure
o DNA replication
· Protein Synthesis
o RNA structure and types of RNA
o Transcription
o Translation
· Mutations
· Gene regulation
Revised 1/07