Topic 5h - Animal repro. & dev. Flashcards
Various forms of asexual repro…
budding
regeneration after fission
parthenogenesis
Gametogenesis (formation of sperm & eggs) is the result of …?
meiotic division of germ cells
How many sperm produced per day?
100 million
Acrosome contains …?
digestive enzymes
What is oogenesis?
production of eggs
occurs in ovaries
When does oogenesis begin?
during embryonic development of the female
Re fertilisation, sperm swim up …?
fallopian tubes
Re fertilisation, entry of sperm triggers…?
resumption of meiosis (nucleus of egg & nucleus of sperm)
What is indirect dev?
Immature often bears no resemblance to adult
mainly in amphibians & invertebrates
lots of eggs produced
immature to adult via METAMORPHOSIS
What is direct dev?
Immature resembles adult require more nourishment eggs provisioned with yolk embryos incubated inside females body survivorship to adulthood much higher
Cleavage of zygote forms …?
morula
What is the site where gastrulation begins?
blastopore (mesoderm)
What does the endoderm form…?
primitive gut