Heredity CH12 pg 267 Sexual Reproduction Combining of a sperm cell and an egg cell from two individuals The offspring of this cross will have characteristics from both parents hybrid ID: 230378
Download Presentation The PPT/PDF document "Mendelian" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1Slide2
Mendelian
Heredity
CH12
pg
267Slide3
Sexual Reproduction
Combining of a sperm cell and an egg cell from two individuals
The offspring of this "cross" will have characteristics from both "parents“
hybridSlide4
Self – Pollination
Contrasting traits, easy to grow and reproduceSlide5
Heterozygous 3:1 RatioSlide6
Characters
vs TraitsSlide7
Mendel’s Laws of Heredity
Law of Dominance -
One factor (trait) in a pair may mask the effect of the other. Slide8
Law of Segregation -
The two traits for a characteristic separate during the formation of eggs and sperm.
Mendel’s Laws of HereditySlide9
Law of Independent Assortment -
The traits for different characteristics are distributed to reproductive cells independently. pg272
Mendel’s Laws of HereditySlide10
Using
Punnett Squares
Punnett
Square
Model that predicts the likely outcomes of a genetic cross with the alleles taken from the parents
Shows all the genotypes that could result from a given crossSlide11
How to for
Punnett Square
Capital letter
D
ominant trait
Letter represents trait (B for brown)
Dominant always written first in sequence (Bb)
Lower case letter
r
ecessive trait
same letter as dominant trait (b for blond)Slide12
Monohybrid Cross
Contrasting traits (purple
vs
white flower)
Homozygous Cross (PP or pp)
Heterozygous Cross (Pp)
Paternal alleles across the top
Maternal alleles down the left side
Slide13
Monohybrid Cross
Phenotype
Genotype
Slide14
Using Probability
Likelihood that a specific event will occur
Probability
=
# of one kind of possible outcomes
total # of all possible outcomes
Probability of a specific allele in a gamete
Represented as a fraction or ratioSlide15
Probability in a
Heterozygous Cross
Flipping a coin/ possible alleles
Both parents have Pp, How do you know?
P
p
P
pSlide16
Using a Pedigree
Several generations
Determine genetic disorders or diseases that can be inherited
Pedigrees can help answers questions about the three factors of inheritance
Sex-linked Genes
Dominant or Recessive
Heterozygous or HomozygousSlide17
Many Genes, Many Alleles
Polygenic Inheritance
Several genes affect characteristic
Relative greenness or brownness, blue eyes are recessiveSlide18
Many Genes, Many Alleles
Incomplete Dominance
Intermediate between traits
Snapdragon (red and white = pink)Slide19
Many Genes, Many Alleles
Multiple Alleles
3 or more possible alleles, only to alleles for a gene can be present
Complex dominance
Blood types and Labrador coat colorSlide20
ABO blood groupsSlide21
Many Genes, Many Alleles
Codominance
Both Alleles for the same gene are fully expressedSlide22
Genes affected by the Environment
Nutrients and temperature
Personality and behaviorSlide23
Genes Linked Within Chromosome
Genes that are close together are less likely to be separated than genes that are far apart