In birds: females are ZZ and males are ZW females are ZO and males are ZZ females are XX and males are XY females are XX and males are XO females are ZW and males are ZZ

Nuptial gift in crickets: duormous are male Understand the examples of species with sex-role reversal. Sex role reversal In some empid fies, the operational sex ratio is heavily female biased, because most males are off hunting for insect prey that is used as a nuptial gift When a male enters the swarm with a nuptial gift. he may find females advertising themselves with unusually large patterned wings, legs or abdomen. Is this always the case? m le diaclans Sex role reversal Sex role reversal Pipefish males have a brood pouch in which females lay their eggs. Provide nutnients and oxygen for a clutch of eggs for several weeks (male "pregnancy") Females compete formales. Males how more interest in feeding thanin mating. transfers to the female an spermatophore (-24% of the male's body mass). Males can only afford to mate orice. qpa cs Scanned with CamScanner

An F, generation is the result of which mating described below? Select one: O a. Randomly mating any two parents of opposite sex together. cross out O b. Mating a true breeding female to a true breeding male. cross out O c. Mating the offspring of an F, generation back to their parents. cross out cross out O d. Mating any F, male to any F, female. cross out O e. Allowing the individuals from a single F, generation to mate among themselves. Clear my choice

hich of the following is least likely to produce genetic variation in the offspring of an individual? a cross over event during meiosis that creates a new combination of alleles in the gametes a DNA replication error caused by DNA polymerase in a body cell of the individual the random fertilization of an egg cell by a sperm cell during sexual reproduction independent assortment of chromosomes during meiosis that creates a new combination of alleles in the gametes