Chapter 11 Unit 3 Flashcards
Are lower plants haploid or diploid?
They are haploid
Does mitosis or meiosis produce gametes?
Meiosis
What do gametes contain?
They contain half the chromosomes of ordinary body cells.
What is the abbreviation for diploid?
2N
How many sets of humongous chromosomes are in body or somatic cells?
There are 2 sets.
For each germ cell how many gametes do you get?
You get four.
What does sexual reproduction include?
Fusion of gametes to produce a 2N zygote.
Life cycles of sexually reproducing organisms involve what?
Alternation of haploid and diploid phases.
Some life cycles have dominate what phases and some have dominant what phases?
diploid and haploid
What is meiosis 1?
It is the division of 2 cells
What is meiosis 2?
It is the division of those 2 cells
What does meiosis 1 and 2 result in?
The division of one 2N cell into four genetically distinct 1N cells
What is the abbreviation for haploid cells?
1N
What is the first tissue to develop?
The heath
Where exactly do the chromosomes come from?
1-22 come from mom, 1-22 come from dad and 2 are sex chromosomes
When does synapsis and crossing over occur?
It occurs during Prophase 1
What is synapsis?
It is where homologues chromosomes line up across from each other following replication.
Proteins between the homologues hold them in a what?
A synaptonemal complex
What does crossing over occur between?
non-sister chromatids
What is crossing over?
It is genetic recombination between non- sister chromatids
What is the site in which cross overs happen?
Chiasmata
When there are numbers by the phases is that mitosis or meiosis?
It is meiosis
Describe Prophase 1.
Homologues chromosomes pair up= synapsis this forms tetrads. Crossing over. Arms of sister chromatids held together at region called terminal chiasmata.
Describe Metaphase 1.
Homologues pairs line up on metaphase plate and double row because meiosis.
Describe Anaphase 1
Homologous chromosomes separate and migrate to separate poles.
Describe telophase 1
Sister chromatids reach opposite poles and form new haploid cells.
What does meiosis 2 resemble?
Mitosis
Describe Prophase 2
Nuclear envelopes dissolve and spindle apparatus forms
Describe Metaphase 2
Sister chromatids align on metaphase plates, and cohesion proteins dissolve
Describe Anaphase 2
Sister chromatids separate
Describe Telophase 2
Nuclear envelope re-forms and cytokinesis follows.
What is haploid in?
Meiosis
What is diploid in?
Mitosis
In what do sister chromatids remain joined to their centromeres?
Meiosis 1
Random or independent assortment of homologues happen where?
Metaphase 1
Mitosis produces 2 daughter cells what to the mother cell?
Identical
What do plants have with both multicellular diploid and multicellular haploid stages?
Alternative of multicellular generations
What does haplodiplontic mean?
Having multicellular haploid and diploid stages.
What is where meiosis in 2N plants produce 1N spores that germinate into 1N plants?
Sporic meiosis
In 1N plants in turn produce 1N gametes via what?
Mitosis
