3/6 Flashcards
What are the genetic combinations for insect sex determination?
XX females and XO males, XX females and XY males, ZW females and ZZ males
Different letters are used when the male is the heterogametic sex.
What is the role of Wolbachia in insect reproduction?
Highjacks host reproduction, spreads through the population
It influences offspring sex ratios and can feminize male offspring.
What is cytoplasmic incompatibility?
A cross between an infected male and uninfected female doesn’t work.
How does Wolbachia interfere with male production in Hymenoptera?
By doubling the egg genome, resulting in female offspring.
What is the typical reproduction method for most insects?
Diploid with sex chromosomes in addition to the autosomes.
What is the effect of bacterial infection on insect offspring sex ratios?
Infection can skew the sex ratio, promoting female-biased reproduction.
What is copulation in insects?
The direct transfer of sperm from male to female.
What is a spermatophore?
A package that contains sperm, often used during copulation.
How do male accessory gland secretions function during copulation?
They form the spermatophore and serve as lubrication.
What is unique about the copulation system in Odonates?
Males transfer sperm to a storage organ at the front of their abdomen.
What is mate guarding in insects?
A behavior where the male keeps the female in his grip to prevent her from mating with other males.
Why do males engage in mate guarding?
To ensure their paternity when females may copulate with multiple males.
What is the sexual conflict in insect reproduction?
A struggle to determine paternity between mating partners.
What is traumatic insemination?
A mating strategy where the male pierces the female abdomen to transfer sperm.
What is the term for asexual reproduction in insects?
Temporary strategy where species can reproduce sexually or asexually.
What is mitotic parthenogenesis?
A method where females produce females without fertilization.
What is oviposition?
The process of laying eggs.
What is the typical structure of an insect egg?
Large yolk with most cytoplasm as a thin layer on the periphery.
What occurs during fertilization in insects?
Nuclear divisions happen without cell formation, forming a blastoderm.
What marks the beginning of gastrulation in insect development?
Cells at one pole become columnar and fold into the yolk.
What are the three germ layers formed during embryonic development?
Ectoderm, mesoderm, and endoderm.
What are the basic steps of molting in insects?
- Apolysis * Formation of the new cuticle * Ecdysis
What happens during apolysis?
The epidermis retracts from the cuticle.
What is ecdysis?
The shedding of the old exocuticle/epicuticle.
