Part 1: Genetics
Unit 1:
UnderstandinG BioloGical inheritance
Specific Learning Outcomes 3
Principles of Inheritance 4
Autosomal Inheritance 12
Atypical Inheritance 18
Sex-Linked Inheritance 24
Using Pedigrees 28
Genetic Testing 32
Genetic Variability 40
Chromosome Mutations 44
Unit 1 Appendices 49
,
,Unit 1: Understanding Biological inheritance
specific learning outcomes
B12-1-01: Outline Gregor Mendel’s principles of inheritance, stating their importance to
the understanding of heredity. (GLOs: A1, A2, B1, D1)
Include: principles of segregation, dominance, and independent assortment
B12-1-02: Explain what is meant by the terms heterozygous and homozygous.
(GLO: D1)
B12-1-03: Distinguish between genotype and phenotype, and use these terms
appropriately when discussing the outcomes of genetic crosses. (GLO: D1)
B12-1-04: Use Punnett squares to solve a variety of autosomal inheritance problems, and
justify the results using appropriate terminology.
(GLOs: D1, E1)
Include: monohybrid cross, dihybrid cross, testcross, P generation, F1 generation,
F2 generation, phenotypic ratio, genotypic ratio, dominant alleles, recessive alleles,
purebred, hybrid, and carrier
B12-1-05: Describe examples of and solve problems involving the inheritance of
phenotypic traits that do not follow a dominant-recessive pattern. (GLO: D1)
Examples: co-dominance, incomplete dominance, multiple alleles, lethal genes . . .
B12-1-06: Explain the basis for sex determination in humans. (GLO: D1)
Include: XX and XY chromosomes
B12-1-07: Describe examples of and solve problems involving sex-linked genes.
(GLO: D1)
Examples: red-green colour-blindness, hemophilia, Duchenne muscular dystrophy . . .
B12-1-08: Use pedigree charts to illustrate the inheritance of genetically determined traits
in a family tree and to determine the probability of certain offspring having
particular traits. (GLOs: C8, D1)
Include: symbols and notations used
B12-1-09: Discuss ethical issues that may arise as a result of genetic testing for inherited
conditions or disorders. (GLOs: A3, B1, B2, C4)
B12-1-10: Discuss the role of meiosis and sexual reproduction in producing genetic
variability in offspring. (GLOs: D1, E3)
Include: crossing over and randomness
B12-1-11: Explain how chromosome mutations may arise during meiosis. (GLOs: D1, E3)
Include: nondisjunction
B12-1-12: Identify monosomy and trisomy chromosome mutations from karyotypes.
(GLO: D1)
Examples: Down syndrome, Turner syndrome, Klinefelter syndrome
, Grade 12 BioloGy • Unit 1: Understanding Biological Inheritance
SPECIFIC LEArnInG OUtCOMES
B12-1-01: Outline Gregor Mendel’s principles of inheritance, stating
P rinciPles of their importance to the understanding of heredity.
(GLOs: A1, A2, B1, D1)
i nheritance
Include: principles of segregation, dominance, and independent
assortment
B12-1-02: Explain what is meant by the terms heterozygous and
homozygous. (GLO: D1)
B12-1-03: Distinguish between genotype and phenotype, and use
these terms appropriately when discussing the outcomes of
genetic crosses. (GLO: D1)
sUGGestions for instrUction
SLO: B12-1-01
SLO: B12-1-02
SLO: B12-1-03
teacher BackGroUnd
The instructional strategies suggested in this document follow the constructivist
model of learning and are organized into two groups: activate and acquire/apply.
By activating students’ prior knowledge of a topic, teachers can
• help students relate new information, skills, and strategies to what they already
know and can do
• recognize misconceptions and gaps in student knowledge
• stimulate curiosity and initiate the inquiry process
Acquiring and applying strategies are designed to assist students in processing,
integrating, and consolidating their learning.
entry-level knowledGe
Students were exposed to basic Mendelian genetics in Grade 9 Science. Dominant
and recessive genes were discussed, and the terms genotype and phenotype were
introduced.
teacher note
Students generally find the study of genetics interesting. Once they learn the
specialized vocabulary and conventions (e.g., Punnett squares), the concepts can be
easy to grasp.
Ensure students understand that Gregor Mendel had no preconceptions about
chromosomes, genes, or deoxyribonucleic acid (DNA). He based his principles
solely on the numbers of offspring he observed. The scientific process Mendel used
could be a theme during instruction for learning outcome B12-1-01.
4 – Understanding Biological inheritance
Unit 1:
UnderstandinG BioloGical inheritance
Specific Learning Outcomes 3
Principles of Inheritance 4
Autosomal Inheritance 12
Atypical Inheritance 18
Sex-Linked Inheritance 24
Using Pedigrees 28
Genetic Testing 32
Genetic Variability 40
Chromosome Mutations 44
Unit 1 Appendices 49
,
,Unit 1: Understanding Biological inheritance
specific learning outcomes
B12-1-01: Outline Gregor Mendel’s principles of inheritance, stating their importance to
the understanding of heredity. (GLOs: A1, A2, B1, D1)
Include: principles of segregation, dominance, and independent assortment
B12-1-02: Explain what is meant by the terms heterozygous and homozygous.
(GLO: D1)
B12-1-03: Distinguish between genotype and phenotype, and use these terms
appropriately when discussing the outcomes of genetic crosses. (GLO: D1)
B12-1-04: Use Punnett squares to solve a variety of autosomal inheritance problems, and
justify the results using appropriate terminology.
(GLOs: D1, E1)
Include: monohybrid cross, dihybrid cross, testcross, P generation, F1 generation,
F2 generation, phenotypic ratio, genotypic ratio, dominant alleles, recessive alleles,
purebred, hybrid, and carrier
B12-1-05: Describe examples of and solve problems involving the inheritance of
phenotypic traits that do not follow a dominant-recessive pattern. (GLO: D1)
Examples: co-dominance, incomplete dominance, multiple alleles, lethal genes . . .
B12-1-06: Explain the basis for sex determination in humans. (GLO: D1)
Include: XX and XY chromosomes
B12-1-07: Describe examples of and solve problems involving sex-linked genes.
(GLO: D1)
Examples: red-green colour-blindness, hemophilia, Duchenne muscular dystrophy . . .
B12-1-08: Use pedigree charts to illustrate the inheritance of genetically determined traits
in a family tree and to determine the probability of certain offspring having
particular traits. (GLOs: C8, D1)
Include: symbols and notations used
B12-1-09: Discuss ethical issues that may arise as a result of genetic testing for inherited
conditions or disorders. (GLOs: A3, B1, B2, C4)
B12-1-10: Discuss the role of meiosis and sexual reproduction in producing genetic
variability in offspring. (GLOs: D1, E3)
Include: crossing over and randomness
B12-1-11: Explain how chromosome mutations may arise during meiosis. (GLOs: D1, E3)
Include: nondisjunction
B12-1-12: Identify monosomy and trisomy chromosome mutations from karyotypes.
(GLO: D1)
Examples: Down syndrome, Turner syndrome, Klinefelter syndrome
, Grade 12 BioloGy • Unit 1: Understanding Biological Inheritance
SPECIFIC LEArnInG OUtCOMES
B12-1-01: Outline Gregor Mendel’s principles of inheritance, stating
P rinciPles of their importance to the understanding of heredity.
(GLOs: A1, A2, B1, D1)
i nheritance
Include: principles of segregation, dominance, and independent
assortment
B12-1-02: Explain what is meant by the terms heterozygous and
homozygous. (GLO: D1)
B12-1-03: Distinguish between genotype and phenotype, and use
these terms appropriately when discussing the outcomes of
genetic crosses. (GLO: D1)
sUGGestions for instrUction
SLO: B12-1-01
SLO: B12-1-02
SLO: B12-1-03
teacher BackGroUnd
The instructional strategies suggested in this document follow the constructivist
model of learning and are organized into two groups: activate and acquire/apply.
By activating students’ prior knowledge of a topic, teachers can
• help students relate new information, skills, and strategies to what they already
know and can do
• recognize misconceptions and gaps in student knowledge
• stimulate curiosity and initiate the inquiry process
Acquiring and applying strategies are designed to assist students in processing,
integrating, and consolidating their learning.
entry-level knowledGe
Students were exposed to basic Mendelian genetics in Grade 9 Science. Dominant
and recessive genes were discussed, and the terms genotype and phenotype were
introduced.
teacher note
Students generally find the study of genetics interesting. Once they learn the
specialized vocabulary and conventions (e.g., Punnett squares), the concepts can be
easy to grasp.
Ensure students understand that Gregor Mendel had no preconceptions about
chromosomes, genes, or deoxyribonucleic acid (DNA). He based his principles
solely on the numbers of offspring he observed. The scientific process Mendel used
could be a theme during instruction for learning outcome B12-1-01.
4 – Understanding Biological inheritance
