Independent Assortment of Genes Flashcards
What is Mendel’s first law?
Members of a gene pair separate equally into gametes
What is Mendel’s second law?
Independent assortment
What is the phenotypic ratio of an F2 dihybrid cross?
9:3:3:1
What is the product rule?
What is the sum rule?
The Product rule is the probability of independent events ocurring together
The Sum rule is the probability one or another multiple mutually exclusive event occuring
How can you generate pure lines?
Multiple rounds of selfing
Selfing:
When pollen from a flower falls on its own stigma
Self-pollination
Selfing reduces ____
Heterozygosity
How do you homozygos a number of genes into a single pure line?
Crossing different pure lines and selfing their progeny
In many eukaryotes, __ of the products of meiosis die
3
What are recombinants?
Meiotic outputs that differ from meiotic inputs
Individuals with shuffled alleles from their parents
How can you test for recombinants in diploids?
Testcrossing
Independent assortment is expected to produce __% recombinants
50%
Continuous trait:
Influenced by multiple genes
What are genes that influence continuous traits called?
Quantitatve trait loci (QTLs)
or Polygenes
The baseline model for continuous traits is that QTLs behave ___
Additively
Continuous traits: view alleles as countributing ___
One allele ___ provide a dose
One allele ___ ___ provide a dose
alleles contribute doses
one allele WILL
one allele WILL NOT
What organelles in eukaryotes have organellar DNA?
myDNA- Mitochondrial
cpDNA - chloroplast
In humans, genes that were mitochondrial were absorbed by __
the nucleus
In most cases, organelles specifically exhibit ____ inheritance
Maternal
Chloroplast mutations can result in ___
Variegation
Variegation:
Mosaic of cells with functional and nonfunctional chlorplasts
What will the offspring of a variegated plant look like?
It will look like the mother because the maternal genome is what matters.
A heteroplasmic individual ___ ___ show a trait
might not
How can a cell have only one organellar gentoype?
What is it called?
Through sucessive cell divisions
Cytoplasmic segregation
Mitochondrial DNA is inherated from ___
Our moms
Inference:
Alleles that are linked on a chromosome tend to be inherited together
Cis or trans confromation?
AB/ab
++/ab
Cis
Cis or trans conformation?
Ab/aB
+b/a+
Trans
