17.1 Flashcards
Choosing and breeding specific plants and animals for specific features and behavior’s?
Selective Breeding
Who proposed the first widely accepted theory of inheritance?
Aristotle
What did Aristotle say caused inheritance?
- Egg and Sperm consisted of particles (pangenesis) that was derived from all parts of the body
- Upon fertilization - pangenesis develop into parts of the body of which they were derived
What did Antony Van Leuwenhoek say?
- Complete person (homunculus) - in the head of sperm
- Came from father but developed in the mother
Who countered Antony Van Leuwenhoek’s proposal?
Regnier de Graaf - proposed that the egg that contains the entire person, but sperm stimulates the egg to develop
Who laid the foundation of the field of genetics?
Gregory Mendel (Monk and teacher)
How did Mendel lay the foundation of the field of genetics?
He analyzed over 28 000 pea plants in the monastery garden
What did he make sure to search for in the peas he researched?
He chose seven traits that were expressed in two easily distinguished forms
What types of plants exhibit the same characteristics generation after generation?
True breeding plants
What is the F1 generation?
The first set of offspring that is crated by the parent plants
What is the F2 generation
The offspring that is produced from the F1 generation.
What is it called when only one trait is crossed?
Monohybrid cross
The characteristic that is expressed?
Dominant
The characteristic that is not expressed?
Recessive
Do traits that did not appear in the F1 generation reappear in the F2 generation?
Yes
What is Mendel’s first law of segregation?
- All individual’s have two copies of one factor
- Each copy segregates randomly during gamete formation - each gamete receives one copy of every copy
What are alleles?
Different forms of each gene
What is an individual’s genotype?
Combination of alleles for any given trait
What is an individual’s phenotype?
Outward expression of trait that you can observe
What do you call an individual with two identical alleles for a trait such as RR or rr
They are homozygous dominant (RR) or homozygous recessive (rr)
What do you call an individual with two different alleles for a trait?
Heterozygous
How can you know if a phenotypically dominant individual is homozygous or heterozygous?
You can do a test cross with a homozygous recessive plant
What is Waltzer?
A recessive trait in mice that affects inner ear - they run in circles
What is it called when there are two genes involved in a cross?
A dihybrid cross
