1. Alternative versions of genes (alleles) account for variation in inherited characters 2. For each character, an organism inherits two alleles, one from each parent 3. If two alleles differ, one is dominant, the other recessive 4. The two alleles for each character segregate (separate) during gamete production. Genetics: Review
14
Embed
1. Alternative versions of genes (alleles) account for variation in inherited characters 2. For each character, an organism inherits two alleles, one from.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
1. Alternative versions of genes (alleles) account for variation in inherited characters
2. For each character, an organism inherits two alleles, one from each parent
3. If two alleles differ, one is dominant, the other recessive4. The two alleles for each character segregate (separate) during gamete production.
Genetics: Review
F1 Generation
RR rr
Gametes
P Generation
F2 Generation Sperm
Gametes
Red White
R r
RrPink
R r
R r
R
r
RR Rr
rrRr
Eggs12
12
12
12
12
12
Variations in Mendel’s Laws
In incomplete dominance, F1 hybrids have an appearance in between the phenotypes of the two parents.
Homozygousfor ability to make
LDL receptors
Severe diseaseMild diseaseCell
Normal
LDLreceptor
LDL
Homozygousfor inability to make
LDL receptors
HeterozygousHH Hh hh
GE
NO
TY
PE
PH
EN
OT
YP
E
Hypercholesterolemia•Dangerously high levels of cholesterol in the blood.•Is a human trait that is incompletely dominant.•Heterozygotes have blood cholesterol levels about 2X normal.•Homozygotes have blood cholesterol levels about 5X normal.
Variations in Mendel’s Laws
BloodGroup
(Phenotype)Genotypes Red Blood Cells
O
A
B
AB
ii
IAIB
IBIB
orIBi
IAIA
or IAi
Carbohydrate A
Carbohydrate B
Variations in Mendel’s LawsMultiple Alleles
Variations in Mendel’s Laws– Pleiotropy is the impact of a single gene on more than one