Mendel and genetic crosses

Question 1

Define chromosome theory of inheritance

Answer 1

chromosomes are the vehicles of genetic heredity; It describes linkage, recombination, and crossing over, and states that Mendelian genes have specific loci on chromosomes, which undergo segregation and independent assortment.

Question 2

Understand Mendel’s true breading crosses generating F1 followed by F1crosses to produce F2

Answer 2

Mendel’s true-breeding crosses involve crossing two individuals that are homozygous for a particular trait, meaning that they both carry identical alleles for that trait. When these individuals are crossed, their offspring, known as the F1 generation, will all be heterozygous for the trait, meaning that they carry two different alleles for that trait. If the F1 generation individuals are then crossed with each other, their offspring, known as the F2 generation, will have a variety of phenotypes, with some individuals showing the dominant trait and others showing the recessive trait.

Question 3

Know how to use a punnet square to determine the probability of obtaining certain genotypes in a genetic cross

Answer 3

Determine the possible phenotype and genotype of offspring.

Question 4

Mendel’s law of segregation

Answer 4

The law of segregation states that each individual that is a diploid has a pair of alleles (copy) for a particular trait. Each parent passes an allele at random to their offspring resulting in a diploid organism. The allele that contains the dominant trait determines the phenotype of the offspring (Ex: purple and white parents but the purple parent gives the purple trait to the offspring.)

Question 5

Law of independent assortment

Answer 5

the alleles of two (or more) different genes get sorted into gametes independently of one another. All possible combinations of factors can occur in the gametes. In other words, the allele a gamete receives for one gene does not influence the allele received for another gene. (Ex: dihybrid cross)