Part K: Lecture 41 Flashcards
(20 cards)
hybridization
the process of an animal or plant breeding with an individual of another species or variety
hybridization examples
petunias, citrus trees, wheat, mule (female horse x male donkey), sapiens x neanderthals
diploids (def.)
two copies of each chromosome
polyploidy (def.)
adults have more than two of each chromosome
polyploidy: 3
triploid
polyploidy: 4
tetraploid
polyploidy: 6
hexaploid
polyploidy: 8
octoploid
hybrids (AB) are viable because _____
mitosis works
hybrids (AB) are sterile because _____
meiosis fails in prophase I (no homologous chr —>can’t pair)
tetraploid (AABB) are viable because _____
mitosis works
tetraploid (AABB) are fertile because _____
meiosis works (homologous chr —> can pair)
tetraploid formed when ___
hybrid forms and cytokinesis fails after mitosis (double the chr in adult cell)
diploid 2n=14 ; n=7 –> tetraploid ???
2n=28 ; n=14
triploid (AAA) are viable because _____
mitosis works
triploid (AAA) are sterile because _____
meiosis fails (gametes have one or two of each chr)
cultivated bananas don’t ____
have seeds because meiosis fails
animals: hybridization and polyploidy
rare
plants: hybridization and polyploidy
common
humans: hybridization and polyploidy
double fertilization -> polyploidy
triploidy = non-viable usually