Question

1. Animals can teach us genetics. Match Codominance Show a dominant and recessive relationship _An allelic series A dominant homozygote is lethal Coat coloration is determined by 2 genes Shows variable expressivity A qualitative, or continuous, trait involving polygenes Females mosaics for X-linked heterozygous color genes A. Manx cat B. Coat coloration rabbits C. Labrador retriever dogs D. Piebald spotting in beagles E. A and B blood alleles F. A and O blood alleles G. Calico cat H. Height of an individual 2. If Mendel only knew. Fill in EPISTASIS DOMINANCE ALLELE CODOMINANCE INCOMPLETE DOMINANCE PENETRANCE INDEPENDENT ASSORTMENT EXPRESSIVITY RANDOM SEGREGATION a) The expression of both alleles of a heterozygous gene pair is called: b) The degree to which a genotype is expressed in the phenotype: c) The suppression of one gene by another non allelic gene : d) The % of individuals of a genotype that show the expected phenotype: e) Each gamete receives one allele of a gene : f) When heterozygous genotype results in phenotype intermediate to the two alleles g) Alleles of 1 gene pair inherited independently from those of another gene pair h) An alternative form of a gene: i) Expression of one allele to the exclusion of the other in a heterozygote: 3. Examine pedigree Why this is NOT a Y linked trait? Is this inherited in a dominant or recessive manner? Can you tell if this trait is sex linked? OD ooo Do 4. Do you know your numbers? a) number of chromosomes in a human diploid cell b) number of chromosomes in a human haploid cell c) number of chromosomes in a human Turner syndrome cell d) number of chromosomes in a human trisomic cell e) number of chromosomes in a human triploid cell f) number of chromosomes in a human cell with a Robertsonian fusion g) number of chromosomes in a human fertilized egg h) number of chromosomes in a typical human sperm i) number of Barr bodies in the nucleus of a typical human male skin cell J) number of Barr bodies in an XXY male somatic cell

Answer 1

1. Match the following

a )A and B blood alleles

b) A and O blood alleles

c) Height of an individual

d) Manx cat

e) Piebald spotting in beagles

f) Labrador retriever dogs

g) Coat coloration rabbits

h) Calico cat

2. Fill in the blanks

a) Codominance

b) Penetrance

c) Dominance

d) Expressivity

e) Randon segregation

f) Incomplete dominance

g) Independent assortment

h) Allele

i) Epistasis

3. Pedigree analysis

If this is a Ylinked trait then every male born in the family should have this disease, but it is not the case in the given pedigree.

This is inherited in a recessice manner, it is only expressed in when in recessive condition.

Yes this trait is sex X-linked recessive trait. Infemales it is never expressed because of two copies of X chromosome whereas in males when a recessive X is inherited it is expressed.

4. Do you know your numbers

a) 46

b) 23

c) 45

d) 24

e) 69

f) 22

g) 46

h) 23

i) 0

j) 1