Chapter 9 Flashcards
Define fertilization
When male and female reproductive cells join to produce a new cell
What made pea plant flowers good for Mendel’s research?
They can self-pollinate, so they’ll produce genetically identical offspring
Through what process was Mendel able to produce seeds that had 2 different parents?
Through cross-pollination
Define a trait
A characteristic that varies from one individual to another
How many pea plant traits did Mendel study?
7, each with 2 contrasting characteristics
What did Mendel do with each of the 7 plants with contrasting characteristics?
He cross bred them with the plant with the opposite characteristic
What is the original pair of plants called?
The P generation
What is the first generation of offspring (from the P generation) called?
The F1 generation
What is the second generation of offspring called?
F2
What did Mendel know before conducting his research?
That:
- The male part of each flower produces pollen (containing sperm)
- The female part of the flower produces egg cells
Define hybrid
The offspring of 2 organisms with contrasting characteristics
What was Mendel’s first conclusion?
That biological inheritance is determined by factors that are passed from one generation to the next
What are the “factors” mentioned in Mendel’s first conclusion?
Genes
What are the different forms of a gene called?
Alleles
What does the principle of dominance state?
The principle of dominance states that some alleles are dominant and others are recessive
The trait controlled by the recessive allele appeared in how many of the F2 generation in Mendel’s experiment?
25% (1/4)
What does the reappearance of the trait controlled by the recessive allele indicate?
That at some point the recessive allele had been separated, or segregated, from the dominant allele
When did Mendel suggest that the 2 alleles for tallness and shortness segregate?
Mendel suggested that the alleles for tallness and shortness in the F1 plants segregated from each other during the formation of the sex cells, or gametes