University:
Sam Houston State University
Course:
BIOL 2413 | General Zoology
Academic year:

2024
Views:

302

Pages:

10
Author:

StellarSymphony

Inheritance  Discuss genetic inheritance.  Investigate principles of inheritance.  Demonstrate how inheritance plays a role in sex-linked genes  Explain the difference between sexlinked, limited, and influenced inheritance  Genetics are random in nature  Prior to Mendel’s findings • Most widely accepted thought involved a blending theory • If blending theory is true, we would all look the same today • No way to predict the combination of genes in a gamete  Randomness of inheritance is • critical from an evolutionary standpoint • important to the success of artificial selection  For a number of traits, gene expression differs in males and females  The causes fall under 3 categories: 1) Sex-Linked 2) Sex-Limited 3) Sex-Influenced  There are multiple traits that need to be considered when mating animals.  consider that cattle can be horned or polled and white-faced or red-faced.  Polled  Horns and white-faced are dominant and red-faced coloring are recessive. What are the genotypic and phenotypic ratios if two individuals with two pairs of heterozygous genes (each affecting a different trait) are mated? Set up your punnett square Should look like this Now take time to fill in your punnett square  What are the genotypic ratios?  What are the phenotypic ratios? Genotypes – 1 PPWW, 2 PPWw, 2 PpWW, 4 PpWw, 1 PPww, 2 Ppww, 1 ppWW, 2 ppWw, and 1 ppww; Phenotypes •9 polled, white-faced; •3 polled, red-faced; •3 horned, white-faced; and • 1 horned, red-faced offspring.