Genetics Flashcards
(35 cards)
What are homologous chromosomes?
Chromosomes with same length and same genes but different alleles.
Who was Mendel?
He wanted to improve crops and help his bro who got him an education and a place at the monastery. He worked with pea plants and after 20 yrs wrote a paper about inheritable traits.
What are genes?
DNA that encodes for a function/trait. i.e. Eye color
What’s an allele?
Version of a gene.
Genotype?
The allelic makeup (which alleles organism has).
Phenotype?
The appearance of an organism.
What is selfing?
To self means to mate with itself.
How does the pea flower plant self?
The pea plant have both male (stamen) and female (carpel) genitalia. If left, it will self.
Why do you breed?
To find out how many alleles something has.
What did Mendel do to cross two true breeders or a white and purple flower?
Mendel cut off the stamen (sperm) of the white and purple flowers before they matured. Then took a paint brush and got the pollen (mature sperm) of the opposite flower and put it on the opposite carpel.
How did Mendel find out purple was dominant and white flowers were recessive?
Mendel crosses two true breeders (purple x white) and the F1 was all purple flowers!
What is P generation stand for?
True breeding parents/parental cross.
What does F1 stand for?
First generation/filial cross
How did Mendel find out the hidden trait? And the 3:1 ratio?
He crossed a purple and a white and got all purple flowers. They he mates those F1 purple flowers and got 3 purples to 1 white!
What do punnett squares tell you?
They let you know the possible allelic
outcomes of a cross
What does monohybrid mean?
That we’re only looking at one trait!
What does dihybrid mean?
That we’re looking at two genes/traits.
What’s the 9:3:3:1 ration mean?
The more pea pod allelic makeup you count you will always get 9 smooth yellow to 3 wrinkled yellow to 3 smooth green to 1 wrinkled green.
How did Mendel come up with the phenotypic ratio 9:3:3:1?
This ratio was the result of a dihybrid cross between a p1 smooth yellow and wrinkles green. Then for F1 he got 100% yellow smooth. He allowed the F1 to self and got the F2 which had the 9:3:3:1 ratio!
What is an example of incomplete dominance?
Snap dragon plants because if you cross P1 red and white you get pink.
What is the genotypic and phenotypic ratio for snap dragons?
They are the same 1:2:1. 1 red to 2 pink to 1 white
What is an example of a false phenotype?
Hydrangeas! They’re white but they become purple by treating the soil and become pink when sitting on rusty nails. Just look at the ecosystem!
What are autosomes or what does autosomal mean?
Autosomes or autosomal refers to the non sex chromosomes!
What is an example of an autosomal recessive disorder?
Sickle cell anemia which is a recessive disorder (ss).
