ch11 bio310
Page 1: DNA Sequence
Presented DNA sequences indicating genetic material in the subject.
Keywords: BIO310/Genetics / NHM, CTAAAGAT... (sequence continues).
Page 2: Chapter Overview
Topics Covered:
Vocabulary of genetics.
Basic concepts of heredity.
Genetic tools.
Mendelian Inheritance.
Testcross.
Probability and Punnett square.
First and Second Law.
Page 3: Inheritance Types
Overview of types of inheritance:
Pedigree analysis.
Changes in chromosome structure (inversion, duplication, deletion, translocation).
Sources of genetic variation.
Types of inheritance: Dominant-recessive, codominance, incomplete dominance, multiple allele inheritance, sex-linked inheritance, polygene inheritance.
Page 4: Lesson Outcomes
At the end of this chapter, students should be able to:
Define terminologies in genetics.
Describe and explain concepts in genetics.
Explain Mendelian inheritance and types of inheritance.
Apply genetic tools to predict inheritance of traits.
Describe abnormalities in chromosome number and structure.
Page 5: Genetics Terms
Key Terms:
Homozygous, recessive, dominant.
Mendel’s 2nd and 1st laws.
Definitions of gene, genotype, phenotype, allele, heterozygous, incomplete dominance, codominance, trisomy, autosomal, recessive, dominant, sex-linked, chromosome duplication, nondisjunction.
Page 6: Heredity
The development of an individual is guided by gene-bearing chromosomes from parents (egg and sperm).
Genes are segments of DNA that serve as blueprints for protein synthesis and influence traits such as hair color, sex, and blood type.
Page 7: Basic Concepts of Heredity
Vocabulary of Genetics:
Genetic: science of genes, heredity, variation in living organisms.
Genome: all DNA in haploid chromosome set of a species.
Page 8: Basic Concepts of Heredity (continued)
Chromosome: double-stranded DNA carrying genetic information.
Gene: stretch of DNA that determines a specific trait.
Allele: matched genes at the same locus on homologous chromosomes.
Page 9: Gene vs. Allele
Gene: section of DNA controlling a trait (e.g., eye color, blood type).
Allele: specific variation of a gene (e.g., blue eyes, AB blood type).
Page 10: Recombinant Alleles
Recombinant: new combination of alleles compared to parental genotype.
Page 11: Chromosomes & Genes
Homologous chromosomes carry two alleles at corresponding loci.
Unique combinations are formed during meiosis.
Page 12: Genotype vs. Phenotype
Genotype: inherited alleles defining an individual.
Phenotype: observable traits (e.g., flower color).
Homozygous: identical alleles (AA, aa); Heterozygous: different alleles (Aa).
Page 13: Dominant vs. Recessive
Dominant allele: masks the trait of another allele.
Recessive allele: visible only in homozygous condition.
Genetic representations:
Homozygous dominant (AA), homozygous recessive (aa), heterozygous (Aa).
Page 14: Genetics Ratios
Phenotypes of pea plants:
3:1 ratio in dominant-recessive characteristic expression.
Visual examples of genotype ratios (1:2:1).
Page 15: Traits and Their Expression
Many genetic traits have dominant and recessive forms, e.g., cleft chins, widow's peak.
Page 16: Genetic Variation Sources
How are genes sorted into gametes?
Independent assortment of chromosomes.
Crossing over during meiosis.
Random fertilization.
Page 17: Testcrosses and Probability
Testcross:
Cross between unknown genotype and homozygous recessive to determine the unknown.
Probability: chance of genetic outcomes (e.g., BB x bb).
Page 18: Punnett Squares
Punnett Square:
Tool for predicting genetic crosses and probabilities.
Page 19: Gregor Mendel
Father of genetics who studied inheritance in pea plants.
Established foundational principles of heredity.
Page 20: Mendelian Inheritance Principles
Gene transmission from parents to offspring through loci on chromosomes.
Law of segregation: alleles segregate during gamete formation.
Page 21: Mendel's Experiments
Notable traits studied included pod color (green vs. yellow).
Pure-breeding plants and results of F1 and F2 generations.
Page 22: The Law of Segregation
Four main concepts:
Alternative forms for genes exist.
Inheritance of two alternatives (alleles) for traits.
Alleles segregate during gamete formation.
Dominance: one allele may be expressed over the other.
Page 23: Independent Assortment
Concept that allele pairs segregate independently during gamete formation.
Page 24: Pedigree Analysis
Process for tracking inheritance of traits within families.
Page 25: Types of Chromosomal Changes
Duplications, inversions, translocations, deletions, nondisjunction.
Page 26: Chromosome Structure Changes
Physical disturbances can cause gene mutations.
Common alterations leading to genetic disorders.
Page 27: Non-disjunction Examples
Chromosomal anomalies like Down syndrome and Turner syndrome.
Page 28: Types of Inheritance Summary
Dominant-recessive, autosomal, and sex-linked traits.