Biology
CH. 6- Advanced Genetics
6.1 Changes Affecting the Numbers of
Chromosomes
• Objectives:
• Explain the difference between euploidy and aneuploidy
• Discuss the advantage of polypoid organisms
• Describe how nondisjunction affects the chromosome
number
Difference of Euploidy and Aneuploidy
• Euploidy: the condition of having a chromosome number
that is an exact multiple of the haploid number for that
organism.
• Triploids- Pg. 129
• Tetraploids- Pg. 129
• Aneuploidy: either lack chromosomes or have extra one.
• Down Syndrom
• Turner Syndrome
• Klinefelter Syndrome
• Trisomy X (XXX)
• See Pg. 132
The Advantage of Polypoid Organisms
• Read Page 131 to yourself quietly. Be ready for discussion
• Benefits: Focus on 2nd to last paragraph, Pg. 131
How Nondisjunction Affects Chromosome
Number
6.2 Mutations
• Objectives:
• Define Mutation
• Compare and contrast the changes within a chromosome
• Discus the differences between somatic and germ cell
mutations
Mutations
• Any change in the DNA of an organism
Changes within a chromosome and changes
within a gene
• Translocation- Two nonhomologous chromosomes
exchange genetic information during meiosis. Pg. 133
• Deletion- Complete loss of a segment of the
chromosome. Pg. 134
• Inversion- Segment of the chromosome breaks off and
reattaches at the same position but with the genes in
reverse order or inverted. Pg. 135
Changes within a chromosome and changes
within a gene, Cont.
• Substitution- occurs when nucleotide in the DNA sequence is
removed and replaced with different nucleotide or when two
nucleotides are inverted. Pg. 135
• Nucleotide Addition- extra nucleotide is placed in the DNA
sequence. Pg. 135
• Nucleotide Deletion- Opposite of Addition, a nucleotide is
removed from the DNA. Pg. 135
Differences between somatic and germ
cell mutations
• Somatic Mutation- occurs in the nongamete, or body,
cells of the organism. Three possible Effects:
• Produce an odd protein
• Have no effect
• Kill the cell
• Germ Mutation- mutation in a gamete or a cell that
forms gametes
6.3 Gene Expression
• Objectives:
• Define gene expression and cellular differentiation
• Compare and Contrast molecular and environmental
controls on gene expression
• Explain the relationships between cancer and the
functions of proto-oncogenes and tumor suppressor
genes
Define gene expression and cellular
differentiation
• Gene Expression- the activation of a gene that results in its
transcription and the production of a specific protein
• Cellular Differentiation- The specialization of cells that occurs during
embryological development under the control of proteins
Compare and Contrast molecular and
environmental controls on gene expression
• Pg. 138- 139, Read quietly to yourself. Be ready for
discussion
Relationships between cancer and the functions of
proto-oncogenes and tumor suppressor genes
• Tumor- abnormal mass of cells produced by abnormal cell
division
• Benign- cells of tumors that stay within the body of the
tumor and do not spread
• Malignant- cancerous tumors with cells that may spread
(metastasize)
• Carcinogen- any substance that increase the risk of cancer
Relationships between cancer and the functions of
proto-oncogenes and tumor suppressor genes,
Cont.
• Pg. 139-142 (skip brown box), Read quietly to yourself
and be ready to discuss the topic in the above title.
6.4- The Gene Pool
• Objectives:
• Explain the difference between population and gene pool.
• Discuss how mass selection, hybridization, and inbreeding
affect the gene pool.
• Describe desirable as well as undesirable effects of
hybridization.
Difference between population and gene pool
• Population- Group of individuals of the same species
that live in the same area.
• Gene Pool- Sum of all alleles that all members of a
species of an organism can conceivably possess
Discuss how mass selection, hybridization, and
inbreeding affect the gene pool
• Mass Selection- the attempt to cultivate an existing trait…
• Hybridization- crossbreeding of two genetically dissimilar
individuals, crossing two varieties of the same species
• Inbreeding- mating an organism with itself or close relatives.
Produce pure strains
• Pg. 143-144, Read quietly to yourself and be ready to
discuss.
Describe desirable as well as undesirable
effects of hybridization.
• Desirable: often healthier organisms and tend to suffer from fewer
deformities that a purebred. Ex: Mutt (dog)
• Undesirable: danger in having genetic uniformity among a large
number of organisms, allowing the offspring to be much more
vulnerable to environmental changes , viruses, etc.
6.5 Eugenics
• Define Eugenics
• Describe current methods of genetic screening
• Describe two methods of artificial reproduction
Define Eugenics
• Eugenics: “Good Origins” or “Well Born”, the science
that deal with improving the human race by applying
principles of genetics
Current Methods of Genetic Screening
• Pedigree Analysis
• Analysis of the Unborn
• Analysis of the Newborn
• See Pg’s. 148-149, Read quietly to yourself and be
ready to discuss.
Two methods of artificial reproduction
• Artificial Insemination- the mechanical injection of sperm into a
female’s body.
• In Vitro Fertilization- Ova (female egg) is removed from the female’s
body, fertilized in a laboratory by human sperm, and then implanted
back into the woman’s body.