Download presentation
Presentation is loading. Please wait.
Published byDavid Alexander Adams Modified over 9 years ago
1
Unit 3: Heredity Chromosomal Inheritance
Biology 12 Unit 3: Heredity Chromosomal Inheritance
2
The Source of Heredity Chromosome Theory Sex determination
Genes are found on chromosomes Paired chromosomes segregate during meiosis Chromosomes (not genes) segregate independently Each chromosome contains many genes Sex determination In most animals the male of the species has a Y chromosome. Birds are a notable exception - many species of birds has the XY condition as the female
3
Unexpected Results for Linked Genes
5
recombinants
6
Linkage ,Crossing Over & Mapping
B C 12 5 7 BA + AC BC 7 Therefore, A is not in the middle AC + CB = AB 5 + 7 = 12 Therefore, C is in the middle!
7
Sex Linked Inheritance
8
♂ ♀ XN Y ♂ ♀ XN Y Xn ♂ ♀ XN Y Xn ♂ ♀ Xn Y XN ♂ ♀ Xn Y XN ♂ ♀ Xn Y
9
Pedigree Charts
10
Parents Heterozygous Offspring recessive Parents Heterozygous Offspring recessive Inconclusive Parents Heterozygous Offspring homozygous dominant Parents Heterozygous Offspring homozygous dominant Inconclusive
11
IF SEX LINKED RECESSIVE SUSPECTED
CAN’T BE SEX LINKED RECESSIVE MOM COULD BE A CARRIER CAN’T BE SEX LINKED RECESSIVE CAN’T BE SEX LINKED RECESSIVE CAN’T BE SEX LINKED RECESSIVE MOM COULD BE A CARRIER
12
1. What are everyone’s genotype?
I II III IV 1 4 3 2 1. What are everyone’s genotype? 2. What is the probability that III-3 and III-4 will produce another affected offspring?
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.