Bio 104 Exam 1 Study Guide PDF

**Chapters 14, 15, 16: Mendelian and Molecular Genetics** **Mendelian** - Define 'gene locus' and relate this to the concept of homologous pairs. How many copies of each gene locus are present in a diploid organism? When do those copies separate during meiosis? - Be able to relate the...

**Chapters 14, 15, 16: Mendelian and Molecular Genetics** **Mendelian** - Define 'gene locus' and relate this to the concept of homologous pairs. How many copies of each gene locus are present in a diploid organism? When do those copies separate during meiosis? - Be able to relate the concepts of true-breeding, heterozygous, and homozygous. - Describe the relationship between the laws of independent assortment & segregation and the separation of alleles during gamete formation (meiosis). - Define genotype and phenotype. Explain how modes of inheritance link these two concepts. - Describe and be able to recognize examples of the following modes of inheritance: simple dominant-recessive; incomplete or partial dominance; polygenic traits (aka additive genes or quantitative traits); co-dominance; X-linked inheritance. Which of these involve dose-dependent systems? For which modes of inheritance does each genotype map to a unique phenotype? - Relate the concept of dominant-recessive inheritance to the functionality (or non-functionality) of alleles. Extend this physical understanding to your description of incomplete dominance. - Describe the concept of genetic linkage and explain how it affects the gametes that an individual can produce. Relate this to crossing over and recombination frequency. - Describe the relationship between recombination frequency and genetic distance. - Given a straightforward example, be able to figure out: (a) if recombination is occurring, and (b) what the recombination frequency is. - Be able to complete Mendelian genetics problems like those presented in your ALT activity and in the Self-Study Worksheet Genetics. - Describe the structure of a DNA molecule in terms of nucleotides  - Describe the components of an DNA nucleotide. Which parts are uniform, and which vary? - Describe the phosphodiester "backbone" that joins nucleotides together into a strand  - Describe the role of hydrogen bonds in forming the double stranded DNA molecule - Explain the 5' and 3' directionality of a DNA strand and the antiparallel arrangement of the strands  - Apply complementary base pair interactions to predict complementary DNA given a the sequence of a single strand - Identify the functions and purpose of all 7 enzymes that we discussed as making up the replisome - Understand 5'-3' directionality in the context of DNA replication - Understand the role of Okazaki fragments in the synthesis of the lagging strand and be able to describe their orientation and their relationship to the RNA primers produced by primase **Chapter 17: Gene Expression ** Lectures: Genetics -- Gene Expression 1 DNA code; Genetics -- Gene Expression 2 Molecular - Give an overview of the Central Dogma. What are the steps involved and where do they occur? What roles do the following molecules play: RNA polymerase II, transcription factors, mRNA, tRNA, rRNA, ribosomes? - Understand the relationship between the DNA template strand, coding strand, mRNA transcript, and tRNA anticodons. Be able to convert between these four. Always indicate directionality (where the 5' and 3' ends are). - Be familiar with the triplet code of mRNA codons. Use a lookup table (or circle) to convert from mRNA sequences to amino acid sequences. Understand the concept of a 'reading frame'. - Recognize point mutations and insertion/deletion mutations. Be able to further categorize these mutations based on their effects on the amino acid sequences produced (e.g. silent, missense, nonsense, frameshift). - Given multiple examples of mutations, make an educated guess as to which mutation would have a more deleterious (negative) effect on protein function. - Describe the components of an RNA nucleotide. Which parts are uniform, and which vary? - Describe three key differences between DNA and RNA. - Building on your overview of the Central Dogma: be able to outline the steps of transcription. Explain the role of promoters, consensus sequences, and transcription factors. Describe the directionality of the process and the role of complementarity. - Define intron and exon. - Explain how the splicing out of introns is critical to understanding how humans can have only about 20,000 gene loci, but over 100,000 known proteins. - What are the 5' UTR and 3' UTR regions? How are they like the margins on a sheet of paper? - Describe how the 5' cap and poly-A tail are related to post-translational processing. Explain how these two structures are like the aglets on shoelaces. - Outline the steps involved in translation. Make sure that you can explain the role of: anticodons, initiator tRNA and tRNAs in general, the small and large ribosomal subunits, the mRNA binding site, the E, P, and A sites, and release factor. **Chapter 47: Development and Germ Layers ** Lecture: Development and Reproduction - Recognize examples of asexual and sexual reproduction, and related processes. For example, budding is a type of asexual reproduction, while external fertilization is one version of fertilization---a key part of sexual reproduction. - Describe the ways in which sexual reproduction can increase genetic diversity. Relate this to the concept of evolutionary adaptation rate. - Outline the 6 steps in sea urchin fertilization, focusing on the acrosomal reaction, cortical reaction, and egg activation. Which step differs in mammals? - Describe how cleavage divisions lead to the formation of a blastula. How are these divisions different from "normal" cell divisions? - Draw the process of gastrulation in a diploblast and a triploblast. Compare the germ layers formed and their distribution (where they are/go). Recognize examples of diploblasts and triploblasts based on their anatomy. - Know which germ layers become which adult structures in humans (Fig 47.9). Note: you do *not* need to know all the glands (so don't worry about pituitary gland, adrenal medulla/cortex, thymus, thyroid, parathyroid). - Define the term organogenesis. - Be able to define and recognize examples of the following 'related concepts': induction, cell migration, determination and differentiation, cell fate. - Describe the 4 extraembryonic membranes found in humans and reptiles. What functions do they have? How do they differ between humans and reptiles? - Describe the evolutionary pressures believed to have given rise to the amniote development strategy. Relate this to the extraembryonic membranes. - For each of the following terms, know what it is derived from and---if applicable---what it gives rise to: blastocyst; inner cell mass; trophoblast; epiblast; hypoblast; extraembryonic membranes; placenta. You do not need to memorize the full table from your activity. Focus on 'derived from' and 'gives rise to'.