Download Genetics: A Scientific Revolution

Genetics: A Scientific Revolution
Vocabulary:
Gene: a segment of DNA which codes
for a trait
Alleles: one of two versions of a gene
Ex.
- Tall vs. short
- Brown eyes vs. blue
eyes
-Expressed with letters
(WW, Ww, Bb)
Heredity: transmission of traits from
parents to offspring
Inheritance: genes
acquired by offspring
Genotype: alleles that an organism
inherits from its parents
bb
Bb
Bb, BB
Phenotype: appearance of an
organism as a result of genotype
Genotype: bb
Phenotype: blue eyes
Genetics: field of biology devoted to understanding
the patterns/processes of inheritance
Gregor Mendel: Father of Genetics
-born in Austria
-entered a monastery at
age 21
-studied peas
-studied 15 traits over
28,000 generations
-ridiculed for his findings
Pure Trait: traits that show up
generation after generation
P – Generation (parental) – produce
offspring with a mix of pure traits
F1 – Generation (filial) – offspring of
the P-generation
F2- Generation – offspring of the F1
generation
Mendel’s 1st Experiment (Monohybrid
Cross)
P-Generation: Tall Flower X short flower
F1 Generation: (All Tall) Tall X Tall
F2 Generation: 75% Tall; 25% short
Principle of Dominance
Dominant Allele: the allele whose
properties are expresses as phenotype
Recessive Allele: allele whose
properties are not observed
Homozygous: when both alleles are
alike (HH, hh, BB, bb, AA)
Heterozygous: alleles are not alike
(Aa, Hh, Gg)
Law of Segregation: traits separate
during gamete formation
Diploid Cell
Pp Tt
PT
pt
pT
Haploid Cells
Pt
Punnett Square: displays the
probability of genotypes/phenotypes
P-generation
T
T
t
Tt
Tt
t
Tt
Tt
All Tall
F1 Generation – Tt X Tt