Download Biology 3A Exam 3 Study Guide The exam will consist of multiple

Biology 3A
Exam 3 Study Guide
The exam will consist of multiple choice, true-false, “fill-in”, and short answer.
Total of 100 points.
The following is by no means everything on the test. This guide emphasizes main topics that are covered on the test
in one fashion or another. Study your notes, the test is based on the notes given in class. Read your book to back up the
notes given in class. Concentrate on the topics given in class when reading your book. Study groups can help - but you
need to study not just talk! You will really learn the material if you can teach it to someone. Review you lecture notes in
detail. Highlight new terms & concepts. Use the text to complete and correct your notes. Don’t forget to use your text
glossary & index to help define terms and find subjects. If you’re not sure whether you should know something,
either ask or just learn it! If I covered it, it’s fair game. Good Luck!!!
• MITOSIS
Know binary fission. Know the different phases and what is occurring during each. Know the cell cycle. Cytokinesis.
Be able to label a diagram of the different phases. Be able to identify the different phases of both plant and animal
cells undergoing cell division. Differences between plant and animal cells. Difference between chromatin,
chromosomes and chromatids. Know how many chromosomes are in the daughter cells after mitosis. What is mitosis
for?What are the five control factors for mitosis and how they limit cell division? What is the problem with cancer
cells? What are p53 and p 21? Tumor suppressors. What are the possible problems with the cell cycle that can
produce cancer cells? What is tumor (benign & malignant)? What is metastasis? What are telomeres
and telomerases?Functions?How do we fight cancer cells?·Know the difference between karyokenesis
and cytokinesis. Apoptosis and cellular death.
• MEIOSIS
What is the difference between sexual and asexual reproduction? Where does meiosis occur?When does it
occur?Why does it occur?When does it occur? What is spermatogenesis and oogenesis?Products of each?
Know the following terms and how they relate to meiosis: homologous chromosomes, diploid, haploid, gametes,
zygote, syngamy. Be able to label a diagram of the different phases - refer to your text. Know the different
phases of meiosis and how they are different from mitosis? What are the sexual sources for variation? How does
meiosis contribute to genetic variation?What is nondisjunction?Polyploidy? Aneupoidy? Trisomy? Monosomy?
Possible genetic causes for birth defects, etc. Define the following terms and use them in sentences describing
events during meiosis: synapsis, chiasma, crossing over, homologous chromosomes, sister chromatids,
nonsister chromatids, chromosome sets, chrmatin, dipoid, haploid, zygote, gamete
• compare meiosis I with mitosis
• DNA replication - where, when & why does it occur (Chapter 16)
DNA structure, bacteriophages, transformation. Be prepared to draw, label & explain a diagram of the replication fork
(Figure 16.16). structure of DNA - nitrogenous bases, 5 carbon sugar, phosphate group. types of bonds involved
Chargoff’s rule - base pairing of the nitrogenous bases (A = T and C ≡ G). enzymes involved in DNA replication (helicase,
single-strand binding protein, DNA polymerase, topisomerase, primase, DNA ligase) and their respective roles. know
chromosome organization: chromatin, histone proteins, nucleosome, heterochromatin, euchromatin, loop domains.
priming, 5’ --> 3’ direction. origins of replication, replication bubbles (why do eukaryotes have many whereas prokaryotes
only have one?), replication fork, parent strand, leading strand, lagging strand (Okazaki’s fragments) - what joins the
fragments together. proofreading, DNA repair, repair enzymes and excision repair, nucleases (endo vs. exo), know the
types of DNA damage
• Protein synthesis - where, when & why does it occur? (Chapter 17)
Be prepared to draw, label & explain a diagram of transcription, RNA processing & translation (Figure 17.25). Know triplet,
codon, anticodon - how are they formed and how they function. Explain all the steps of protein synthesis, including
transcriptional and translational steps. Transcription - where does it occur and what is involved: initiation site, TATA box,
promoter region, termination site. RNA polymerase III (what are their roles), pre-mRNA, mRNA, tRNA, rRNA, cRNA. RNA
processing, RNA splicing -- what are introns and exons; 5’ cap, poly-A tail, spliceosomes, snRNA, snRNP. What’s the
significance of introns and exons. Translation- where does it occur and what is involved: tRNA, anticodon, triplet, amino
acid attachment site, amino acids, aminoacyl-tRNA synthetase. what’s inosine? the wobble hypothesis? Where does it
occur? What can happen when it occurs? mRNA role - binding site: How are the E, P & A sites used? What is the role of
ribosomes? Polyribosomes? Composition of rRNA. What are ribozymes? How do they work? What is the significance of
having DNA as opposed to RNA as the genetic material? Mutations: point (substitution) and frameshift (insertions &
deletions). Know which type of mutation is more detrimental to the organism and why? Are all mutations bad? What’s
the raw material for natural selection? Know difference between transposons and retrotransposons.
• Control of Gene Expression (Chapter 18)
Operons: operator, repressor, regulatory gene, corepressor and how these operons work. Lac operon (Lac Z, Lac Y &
Lac A genes) Lac I repressor, Lac ZYA transcriptional unit (Figure 18.21). Trp operon (five genes involved) -> for
biosynthesis of tryptophan (Figure 18.20)
Understand how these two operons are turn “on” and “off”.
Understand the various mechanisms on how eukaryotic cells control gene expression. We discussed several: differential
gene expression, regulation of chromatin structure, epigenetics, regulation of transcription, RNA processing, mRNA
degradation, protein processing & degradation.
DNA technology (Chapter 20)
What is recombinant technology and its importance to humans and agriculture? Know how genes are produced (copied)
in mass quantities (plasmids of bacteria). Know the difference between PCR and RFLP. What are restriction enzymes?
Would PCR or RFLP utilize restriction enzymes? Understand the PCR lab – use your lab as a reference.
• Genetics (Ch 14 & 15)
Know the following terms: character; trait, monohybrid and dihybrid crosses, P1, F1 & F2 generations, test cross, genotype,
phenotype, homozygous, heterozygous, complete dominance, incomplete dominance, codominance, multiple alleles,
polygenic inheritance, consanguinity, phenocopy, heterophylly, plieotropy, epistasis, sex-influenced traits
Know how to do the genetic problems on the worksheets - there will be several problems on the exam. Rules of
multiplication & addition and how to use them to solve genetic problems. What are sex-linked genes? Mendel’s laws for
segregation and independent assortment. Know the genotypic and phenotypic ratios discussed in class. Know the
dominantly, recessively and sex-linked inherited disorders discussed in class. Linked genes, X-inactivation, Barr body,
Lyon hypothesis, Sex determination, SRY gene, TDF, MIF. Know the 4 chromosomal alterations discussed. Be able to do
a pedigree analysis.
• People to know:
• Griffith; Avery, McCarty & McLeod; Hershey & Chase; Watson & Crick; Franklin; Wilkins; Chargaff;
• Mendel, Morgan, Lyon, Stuarvant