Presentation on theme: "Genetics Kirsten Adams National Cathedral School AP Biology."— Presentation transcript:
Genetics Kirsten Adams National Cathedral School AP Biology
Figure 14.0x Mendel
Figure 14.1 A genetic cross
Figure 14.2 Mendel tracked heritable characters for three generations
Figure 14.x1 Sweet pea flowers
Figure 14.3 Alleles, alternative versions of a gene
Table 14.1 The Results of Mendels F 1 Crosses for Seven Characters in Pea Plants
Figure 14.x2 Round and wrinkled peas
Figure 14.4 Mendels law of segregation (Layer 2)
Figure 14.5 Genotype versus phenotype
Figure 14.6 A testcross
Figure 14.7 Testing two hypotheses for segregation in a dihybrid cross
Figure 14.8 Segregation of alleles and fertilization as chance events
Problem #1 In garden peas, tallness is dominant and dwarfness is recessive. A heterozygous tall plant is crossed with a dwarf plant. If 40 offspring are produced, how many will be tall?
Problem #2 In humans, brown eyes are dominant over blue eyes. A brown-eyed man and a blue- eyed woman have two blue-eyed children. What are the chances that their next child will have blue eyes?
Problem #3 Cystic Fibrosis is inherited as a simple autosomal recessive. Suppose a woman who carries the trait marries a normal man who does not carry it. What percent of their children would be expected to have the disease?
Problem #4 Classical Albinism is a single-gene disorder caused by the lack of an enzyme necessary for the synthesis of melanin pigments. Enzyme production requires the presence of one normal allele. What progeny and what proportions are expected from a normally pigmented woman who has an albino husband and an albino father?
Problem 5 If two individuals with the genotype A/a B/b C/c D/d mate, what is the probabilty of getting an individual with the genotype A/A B/b c/c D/d?
Problem #6 In watermelons, the genes for green color and for short shape are dominant over alleles for striped color and long shape. A plant that is heterozygous for green color and homozygous for short shape is crossed with a plant that is homozygous for striped color and heterosygous for short shape. What proportion of their offspring will be striped and short?
Incomplete Dominance and Codominance
Figure 14.9 Incomplete dominance in snapdragon color
Figure 14.9x Incomplete dominance in carnations
Problem #7 In snap dragons, flower color and leaf color are both controlled by partial dominance. Pink flowers and light green leaves are the intermediate conditions. Supposed you crossed two plants, both of which had pink flowers and light green leaves. If there were 16 offspring, how many would you expect to have both pink flowers and light green leaves?
Multiple Alleles Ex. Blood types
Figure Multiple alleles for the ABO blood groups
Figure 14.10x ABO blood types
Problem 7 A woman takes Mr. X to court for child support, but Mr. X swears he is not the father. The woman is blood type A and the baby is blood type A. Which blood type must Mr. X have to prove that he is not the father?
Figure Pleiotropic effects of the sickle-cell allele in a homozygote
Figure An example of epistasis
Problem 8 If the dominant allele K is necessary for hearing, and the dominant allele M of another gene results in deafness no matter what other genes are present, what percentage of the offspring produced by the cross between k/k M/m and K/k m/m will be deaf?
Multiple Gene Inheritance
Figure A simplified model for polygenic inheritance of skin color
Environment Penetrance Expressivity
Figure The effect of environment of phenotype
Sex linked characteristics Holandric X-linked
Figure 15.3 Sex-linked inheritance
Figure 15.9 The transmission of sex-linked recessive traits
Figure X inactivation and the tortoiseshell cat
Figure 15.10x Calico cat
Figure Pedigree analysis
Figure Large families provide excellent case studies of human genetics
Figure Testing a fetus for genetic disorders
Figure 15.0 Chromosomes
Figure 15.0x Chromosomes
Figure Meiotic nondisjunction
Figure A tetraploid mammal?
Figure 15.x1 Translocation
Figure Alterations of chromosome structure
Figure Down syndrome
Figure 15.x2 Klinefelter syndrome
Figure 15.x3 XYY karyotype
Figure 15.4 Evidence for linked genes in Drosophila
Figure 15.5a Recombination due to crossing over
Figure 15.5b Recombination due to crossing over
Figure 15.6 Using recombination frequencies to construct a genetic map
Figure 15.7 A partial genetic map of a Drosophila chromosome
Linkage Problem In rabbits, a dominant gene produces spotted body color. Another dominant gene produces short hair and its recessive allele long hair. Rabbits heterozygous for both characteristics were mated with homozygous recessive rabbits. The results of this cross were as follows: 170 with spotted and short; 30 with solid and short hair; 26 with spotted and long; 174 with solid and long. What is the map distance between these genese?
Figure Genomic imprinting (Layer 3)
Figure Cytoplasmic inheritance in tomato leaves