Hybridization Flashcards
True or False: If hybrids are less fit, geographical range of ecologically divergent population may be limited, and prezygotic reproductive isolation may be reinforced
True
True or False: If some hybrid genotypes are fitter than one or both parents, then hybridization could make a negative contribution
False; positive contribution
True or False: Single alleles that are at an advantage in the alternative environment and genetic background will introgress readily, such introregregression may be hard to detect
True
when was polyploidy first discovered?
1907
was thought to be responsible for increasing the number of genomic copies that are heritable
polyploidy
condition of having more than two sets of chromosome and also acts as an important mechanism for evolution
polyploidy
Paleopolyploidy is commonly practiced in
plants
most important feature in the evolutionary history of all land plants
paleopolyploidy
True or False; has been observed that approximately every plant has somehow experienced polyploidy at specific point during their evolution
True; paleopolyploidy
True or False: most plants have experienced recent chromosome duplication
True
most plants have experienced recent chromosome duplication known as
neopolyploidy
How many percent of flowering plants (angiosperms) have undergone polyploidy several times during their evolution?
70%
leads to changes in gene dosage that causes chromosomal rearrangements, epigenetic remodeling, and reunion of divergent gene regulatory hierarchies
Polyploidy
changes caused by _______ may bring out novel variations or may result in speciation and reproductive isolation
polyploidy
changes caused by Polyploidy may bring out novel variations or may result in ______ and _______ reproductive isolation
speciation and reproductive isolation
Polyploids may develop naturally by ____ like production of unreduced gametes or may also occur due to unfavorable environmental conditions
cytological mechanisms
occurs when an individual has more than two sets of chromosomes from different species
allopolyploidy
happen through hybridization of two different species that combine different genomes
allopolyploidy
In allopolyploidy, the resulting hybrid is usually _______ because its chromosomes cannot pair correctly.
sterile
Why is allopolyploidy’s resulting hybrid is sterile?
chromosomes cannot pair correctly
True or False: When the resulting hybrid is sterile, it is prevented to mate with the parent populations
True
In alloploidy, formation of a new species can occur if an error in ____ or _____ doubles the chromosome number, and the fertile hybrids can interbreed with each other
meiosis or mitosis
occurs when an individua; has more than two sets of chromosomes, both of which are from the same parental species
autopolyploidy
result from failure of all chromosome to separate during meiosis
autopolyploidy
True or False: Autopolyploidy result from failure of all chromosome to separate during mitosis
False; meiosis
True or False: In autopolyploidy, offspring cannot mate with the parent species
True
True or False: In autopolyploidy, offspring can either be sterile or fertile depending on the combination of gametes
True
True or False: In autopolyploidy, formation of a new species can occur if fertile polyploid offspring can interbreed with each other
True
True or False: Polyploidy can reduce gene flow between the polyploid and normal individual
True
The reduced gene flow caused by polyploidy between polyploid and normal individual leads to _______ where two species from within the same geographic area without geographic separation because the polyploid and normal individual cannot interbreed
sympatric speciation
