AP Bio Chapter 13 Part 1 Flashcards
What are some examples of reproducing asexually (cloning)
Budding hydra
Sprouting redwood
Parthenogenetic rotifers
How do most organisms reproduce
Asexually
Fundamentally, all sexual reproduction involves the same cellular process. Which is?
Fertilization Haploid cell (n) + haploid cell (n) = diploid cell (2n)
What is the haploid number
N
What’s the diploid number
2n
Different SPECIES have different numbers of
Chromosomes
What’s the number of chromosomes in humans in diploid and haploid cells
N=23
2n=46
Where do gametes come from
Ovaries and testes
Show the process from gamete to the first cell of an organism
2 gametes–> a haploid. 2 haploids–>first diploid cell of an organism
Sexually reproducing organisms need to make _______ cells from _________ cells or there would be problems during fertilization
Haploid (gametes)
Diploid
Every diploid cell has __ copies of each chromosome replicated in the ___ phase
2
S
Sister chromatids
The replicated copies of a particular chromosome
Homologous PAIRS
The set of 2 replicated copies of a particular chromosome
Recombinant chromosome
The chromosomes affected by gene switching in crossing over
Meiosis is _______ cell division
Reductive
Where does crossing over occur
Prophase 1
When chromosomes condense during prophase 1, homologous pairs do what to form what
Physically connect to each other (synapsis) to form structures called tetrads
What is the place the chromosomes connect called
Chiasma
What happens at the chiasma
DNA is exchanged between the homologous pairs
What is true about the chromosomes produced from crossing over
They have a unique combination of DNA from both chromosomes in the pair
What affect does crossing over on the gametes
Each of the gametes produced have a unique sequence of DNA in each chromosome
Recombination
Combining DNA from two different sources
What happens in metaphase 1
Homologous pairs of chromosomes line up at the metaphase plate still attached to each other
During separation in anaphase 1 what is separated
Homologous pairs separate
What remains attached during anaphase 1
Sister chromatids
How is this different from mitosis
In mitosis chromosomes line up single file during metaphase
When does the single file arrangement take place in meiosis
Metaphase 2
What is formed in Telophase 1 and cytokinesis and what do the chromosomes consist of
Two haploid cells form, each chromosome still consists of 2 sister chromatids
