Chapter 11 Flashcards
Typically, how many cells contribute genetic material during sexual reproduction?
Two
When two haploid gametes unite, they create a diploid cell called a(n) _____
zygote
An organism is diploid when its cells carry which of the following?
Two sets of chromosomes
In sexual reproduction in eukaryotes, each parent contributes
one set of chromosomes to the offspring.
Which process is responsible for the production of the adult body of an animal from a zygote?
Mitosis
Eukaryotes that reproduce through ______ reproduction require two cells to contribute genetic material for the production of the next generation.
sexual
How many rounds of cell division are required for meiosis?
2
A zygote is created when two haploid cells, called _____, fuse.
haploid gametes
Gametes are haploid. Haploid means that the cells contain how many sets of chromosomes?
One
In sexually reproducing organisms, which type(s) of cell division requires two sequential rounds of division?
meiosis
The structure consisting of paired homologues along a lattice of proteins between them is called what?
Synaptonemal complex
A result of crossing over is genetic ____; this leads to increased genetic variation in the offspring.
recombination
During prophase I, all four chromatids of the two homologues become closely associated as a result of pairing, also known as _____.
synapsis
What involves a physical exchange of DNA segments between homologous chromosomes?
Crossing over
During meiosis, homologous chromosomes become closely associated in the process of pairing, or _____.
synapsis
When the alleles of genes that were formerly on separate homologues can be found on the same homologue which of the following has occurred?
Recombination has occurred
What is the name for the sites of crossing over in a chromosome?
Chiasmata
During which stage of meiosis do synapsis and crossing over occur?
Prophase I
The sites of crossing over are called ______.
chiasmata
In meiosis, when does DNA replication occur?
Before meiosis I only
During _____ I of meiosis, the homologues are pulled toward opposite poles of the cell.
anaphase
The sister chromatids found in the daughter nuclei at the end of telophase I are not identical to each other due to which of the following?
crossing over
Meiosis has how many rounds of DNA replication?
1
At the end of anaphase I in meiosis, each pole of the cell contains which of the following?
A haploid set of duplicated chromosomes
At this stage of meiosis I, the sister chromatids have reached their respective poles, and they then decondense.
Telophase
When meiosis proceeds without recombination, this is referred to as _____ segregation.
achiasmate
When a cell undergoes meiosis, 4 daughter cells are produced. In terms of the number of chromosomes, each daughter cell contains a _____ nucleus.
haploid
When chromosomes do not sort properly during cell division this is referred to as
nondisjunction
After meiosis is complete which of the following are produced?
Four daughter cells that are haploid
The association of homologous pairs guided by heterochromatin sequences is called which of the following?
synapsis
In yeast, the Rec8 protein replaces the Scc1 protein in the cohesin complex during meiosis. Why is this important?
This allows the sister chromatids to stay together during meiosis I
The ____ of sister chromatids are attached to the same pole during meiosis I and to opposite poles during meiosis II.
centromeres
