Show Menu
Cheatography

AP Biology Unit 7: Genetics Cheat Sheet by

Ch 13: Meiosis; Ch 14: Mendelian Genetics; Ch 15: Chromosomes

Meiosis

Mutations

mutation
genetic or chromo­somal (deletion, inversion, transl­oca­tion, polypl­oidy) abnorm­ality
karyotype
diagram that shows size, #, & shape of chromo­somes
nondis­jun­ction
failed separation of homologous chromosomesaneuploidy(trisomy, polyploidy

Chromosome Mutations

 

Mendelian Laws

Law of Dominance
offspring of 2 organisms that are homozygous for 2 opposing traits will be hybrid but will only exhibit the dominant trait and not the recessive trait
Law of Segreg­ation
during formation of gametes, the 2 traits carried by each parent will separate
Law of Indepe­ndent Assortment
alleles of a gene for one trait segregate indepe­ndently from alleles of a gene for another trait (applies w/dihybrid cross)

Genes

linked
genes on the same chromosome
sex-linked
traits carried on X chromosome
linkage mapping
distance between genes on chromosome=chance of separation by crossing over
recomb­ination frequency
=total recomb­ina­nts­/total # offspring x100
pedigree
used to determine how traits are inherited
Barr body
inacti­vated X chromosome in each female mammal's somatic cellgenetic mosaic
 

Types of Crosses

monohybrid cross
Tt x Tt; phenotype ratio=3:1; genotype ratio=­1:2:1
testcross
B/__ x b/b to determine B/__'s genotype
dihybrid cross
TtYy x TtYy; can produce 4 types of gametes & phenotype ratio=­9:3:3:1

Dihybrid Cross

Types of Inheri­tance

incomplete dominance
hybrids show blending of traits
codomi­nance
hybrids show both traits
multiple alleles
more than 2 allelic forms
pleiotropy
1 gene affects an organism in severa­l/many ways
epistasis
2 genes, 1 trait; 1 masks expression of the other
polygenic
blending of several genes that vary along a continuum
               

Help Us Go Positive!

We offset our carbon usage with Ecologi. Click the link below to help us!

We offset our carbon footprint via Ecologi
 

Comments

Great cheat sheet! Thanks for sharing!

Add a Comment

Your Comment

Please enter your name.

    Please enter your email address

      Please enter your Comment.

          Related Cheat Sheets

          Meiosis Cheat Sheet

          More Cheat Sheets by hlewsey

          AP Biology Unit 1: Biochemistry Cheat Sheet
          AP Biology Unit 2: The Cell and Cell Membrane Cheat Sheet
          AP Biology Unit 3: Energy and Metabolism Cheat Sheet