Genotype and Phenotype Quiz

Genotype and Phenotype

• Genotype predicts phenotype of offspring; homozygous recessive (pp) yields all recessive offspring.

Mendel's Laws

• Discovered the principles of dominance, segregation, and independent assortment.

Sex Chromosomes

• Birds and mammals do not have the same sex chromosomes.
• This statement is false for birds and mammals.

Genotype Manipulation

• Animal genotypes can be manipulated through breeding (True).

Karyotype

• A complete set of chromosomes is called a karyotype.

Chromosome Number

• All body cells (except gametes) have a diploid number of chromosomes (True).
• Down syndrome (trisomy 21) results from homologous chromosomes failing to separate during meiosis.

Predicting Offspring Phenotypes

• Parental genotypes can be used to predict offspring phenotypes.
• Cross two heterozygous (Yy x Yy) parents, yielding offspring genotypes YY, Yy, yY, yy.

Codominance

• Heterozygous chickens with black and white speckled feathers are an example of codominance.

Phenotype Factors

• Many factors alter animal phenotype (True).

Gametogenesis

• The term for producing sex cells is gametogenesis.

Genetic Disorders

• Only changes in chromosomes structure, not necessarily number, can cause genetic disorders (False).
• Embryos have diploid (not haploid) chromosome numbers (False).

Mutations

• Harmful mutations make the organism less able to survive, causing death.

Chromosome Components

• Cell components, like eye and hair color, height, and tail length, are examples of phenotypes.

Genotype vs. Phenotype Relationship

• Relation: Phenotype = Genotype + Environment (P=G+E). Two individuals with the same genotype in the same environment would likely have the same phenotype.

Chromosome Number Variations

• Polyploidy: chromosome number is a multiple of the normal haploid (e.g., 3n, 4n).
• Aneuploidy: gain or loss of single chromosome (e.g., monosomy, trisomy).

Chromosome Structure Variations

• Variations: deletions (loss of material), duplications (extra copies), translocations (transfer between chromosomes), inversions (reversed segments).

Mating Systems

• Inbreeding (increases homozygosity)
• Outbreeding (increases heterozygosity). Includes species cross, cross-breeding, outcrossing, grading up.

Animal Domestication

• Animal domestication involves adapting wild animals to domestic use, with factors such as feeding and survivability being prerequisites.

Animal Breeding

• Breeding programs aim to produce uniform animals. Potential negative outcomes from animal breeding include metabolic issues, bone fractures in laying birds, and reduced fertility in dairy cows.