concept 1 Flashcards
Can you summarize Mendal’s experiments?
Mendal used pea plants to learn about genetics, controlling breeding between pea plants, using only purebred plants and only observing “either-or” traits
What are the three laws of inheritance that make up the foundation of Mendelian genetics?
Law of Dominance-
Law of Segregation
Law of Independent Assortment-
What is an example of a monohybrid cross?
Crossing a heterozygous for red plant with a homozygous recessive for white plant. Possibilities would be 50% red and 50% white for offspring.
for pea plant, round seeds are dominant to wrinkled seeds. Cross a homozygous dominant plant with a heterozygous plant.
RR x Rr
Results: RR, RR, Rr, Rr
Genotype ratio: 1:1
Phenotype ratio: 4:0
Cross 2 tomato plants that are both heterozygous tall and red.
TtRr x TtRr
Results: TTRR TTRr TtRR TtRr TTRr TTrr TtRr Ttrr TtRR TrRr ttrr ttRr TtRr Ttrr ttRr ttrr
What are genes?
Sections of DNA that provides the instructions for making a protien
What are alleles?
Different versions of the same gene
What are Homologous chromosomes?
The matching chromosomes from our mom and dad
What does Homozygous mean?
having 2 identical alleles for the same gene
What does heterozygous mean?
having 2 different alleles of the same gene
what does dominant mean?
If present, this allele will always be the trait expressed
what does recessive mean?
allele will only have that trait expressed when the dominant allele is not present
What is a genotype?
the actual alleles inherited
What is a punnett square?
a diagram that shows the probability of inheriting traits from parents with certain genes
What is a monohybrid cross?
The crossing of only 2 alleles
ex. Rr x rr
