Test #3 Study Guide Biol 101 Survey of Biology
Cell division: Meiosis Meiosis is a type of cell division that makes reproductive cells.
Meiosis reduces the diploid number of chromosomes to a haploid number. The two
divisions of meiosis: meiosis I and meiosis II. Understand the distinction between
homologous chromosomes and sister chromatids, and what happens to homologous
chromosomes during meiosis I and sister chromatids during meiosis II.
Differences between male and female meiosis. Down Syndrome and how it resulys from
nondisjunction in meiosis. Correlation between maternal age and chance of having a
baby with an aneuploid syndrome. Amniocentesis as a diagnostic procedure for Down
syndrome.
Mendelian Genetics Simple probability rules. Important terms: Genotype, phenotype
(trait), alleles, dominant, recessive, co-dominant, homozygous dominant, homozygous
recessive, heterozygous, P1, F1, F2. Relationship between genotype and phenotype. The
law of segregation. The basis for the law of segregation in meiosis. Know how to work
with a Punnett square to determine the genotype and phenotype of offspring. Be familiar
with the ABO blood type system (an excellent example of co-dominance and multiple
alleles). The law of independent assortment. Know how to work with a Punnett square
in a dihybrid (two trait) cross. The basis for the law of independent assortment in meiosis.
Examples of recessive and dominant disorders in humans. Human pedigree analysis.
Concept of penetrance and predisposition alleles. Genetics of X-linked traits. Genetic
testing.
Molecular genetics--The structure of DNA. The base pairing rules.
Overview of gene expression: DNA (genes) ----> mRNA ---> Protein
Especially the relationship of DNA sequence to mRNA sequence to amino acid sequence.
The molecular structure of the gene: promoter and transcribed region. (the role of each in
gene function). Structure of RNA. Transcription: synthesis of a messenger RNA copy of
the gene. Know the role of DNA:RNA base pairing in this process.
The genetic code (be able to use the table relating codons to amino acids).
Be able to convert a sequence in mRNA to a protein using the table of the genetic code.
Know that the open reading frame begins with the start codon AUG and ends with a stop
codon (UAA, UAG or UGA). Know the general definition of translation.
Mutation: general definition, types of single base pair substitutions (missense, nonsense
and silent). Implications of somatic and germline mutations.
Mutagenesis (types of mutagens, role of DNA damage and DNA replication in
mutagenesis.
Molecular explanation for HbA and HbS alleles in sickle-cell anemia.