Download Principles of Biology Lake Tahoe Community College

Principles of Biology – Bio 110
Winter Qtr.
Lake Tahoe Community College
Instructor: Sue Kloss
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Chapter 11 – Gene Regulation
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I.
Gene Regulation in Prokaryotes
A. Proteins interact with DNA
1. What is “turned on” in the gene sense?
2. DNA becomes expressed
a. translated into specific protein molecules
3. Control of gene expression
4. learn about gene expression by studying e. coli
a. The lac operon – a repressible operon
b. E. coli uses 3 enzymes
c. Other sequences - Promoter and Operator.
d. Operons usually exist only in prokaryotes
e. What turns the operator on or off?
f. repressor
g. regulatory gene,
h. lactose and the repressor
5. Other kinds of operons – trp operon is inducible
i. Tryptophan
j. Trp operon function and structure
6. A third type of operon uses activators
II.
Cellular Differentiation and cloning of Eukaryotes
A. differentiation – become specialized in structure and function.
1. genes that are active in a cell are the source of its structure and function.
B. Differentiated cells may retain all of their genetic potential
1. differentiation does not necessarily involve permanent changes in the cells DNA.
2. cloning of Dolly the sheep
3. stem cells
III.
Gene Regulation in Eukaryotes
A. DNA packing
1. Each cell has DNA
2. Histones
3. nucleosome
4. tight helical fiber,
5. super coil.
6. DNA packing tends to prevent transcription and translation
B. In female mammals, one x chromosome is inactivated in each cell
1. early in embryonic development.
C. control of eukaryotic transcription
1. eukaryotes have transcription factors
D. Eukaryotic RNA may be spliced in more than one way
E. Translation and later stages of gene expression are also subject to regulation
1. Breakdown of mRNA
2. Initiation of translation
3. protein activation
4. protein breakdown
F. Multiple mechanisms regulate gene expression
1. flow of genetic info into proteins can be modified in multiple ways.
IV. Genetic Basis of Cancer
A. Cancer results from mutations in genes that control cell division
1. oncogenes
5. proto-oncogene.
6. viruses may have a role
7. from conversion of one of cells own genes
8. many oncogenes code for growth factors
9. How proto-oncogene becomes an oncogene
B. interfere with normal signal-transduction pathways
C. Multiple genetic changes underlie the development of cancer
Study Questions/Lesson Objectives Ch. 11
1.
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4.
Describe and compare the regulatory mechanism of the lac operon, the trp operon, and operons using activators.
Explain how DNA is packaged into chromosomes
Describe the process and significance of alternative DNA splicing.
Explain the 7 processes that help regulate gene expression.
5. Explain how viruses, protooncogenes and tumor suppressor genes can each contribute to cancer.
6. Describe the cellular basis for, and the main events in development of colon cancer.
7. Describe behaviors that can increase and decrease your risk of developing cancer.
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Chapter 12 - DNA Technology and Human Genome
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I. Bacteria are tools for manipulating DNA
A. In nature, bacteria transfer DNA in three ways
1. transformation
2. transduction.
3. conjugation
4. integration
5. recombinant chromosome
B. Bacterial plasmids serve as carriers for gene transfer
1. F factor (fertility factor)
2. plasmid
3. origin of replication, required for replication
4. vectors
5. R plasmids carry genes for enzymes that are resistant to antibiotics
C. Plasmids are used to customize bacteria
1. plasmids with inserted genes
Study Questions/Lesson Objectives
Due Wednesday Wk 11
1.
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3.
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6.
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8.
Define and compare recombinant DNA technology, genomics, and proteomics.
What are the goals of the Human Genome Project.
Define and compare transduction, transformation and conjugation.
Explain why bacterial mating is not considered reproduction.
What is the evolutionary significance of bacterial mating?
Describe roles of bacterial F factors.
Define a plasmid and explain why R plasmids pose serious human health problems.
Describe the overall process of using plasmids to give bacteria useful properties.