Life History & Reproduction Flashcards
Define monoecious/hermaphrodite.
An organism which has the sexual organs on the same animal, i.e., one sex.
Define protandric.
Young/small organisms are male, as they grow they become female for brooding eggs.
Define protogynous.
Young/small specimens start out female, become male as they grow.
How are haploid gametes formed?
Through meiosis.
Define stochastic.
Random.
Define asexual reproduction.
Production of new somatic bodies without the process of meiosis or gametes (all by mitosis) at cell level.
What are some of the mechanisms for asexual reproduction?
Parthenogenesis (diploid ova)
Budding
Fission
Define hybridisation.
The result of a sexual cross between parents who are genetically dissimilar.
What are the characteristics of a hybridised organism?
In animals they are nearly always sterile, due to failure of chromosome pairing in meiosis. It’s invoked as a mechanism of speciation.
Define a sub-annual species.
Several generations in one year, possible with diapause (period of suspended development).
Define an annual species with a single mass spawning.
Life period of exactly one year with terminal mass spawning.
Define an annual species with repeated successive spawning.
One year with various periods of spawning.
Define perennial species.
Iteroparous with a single brood per year, or with successive small broods.
Define semelparous.
They are perennial and spawn only once in a life time at a determined age.
Define planktotrophic.
They feed in the water column, have long larval durations and can disperse very far.
