Chapter 10-12
How many base pairs of DNA are wrapped around a single nucleosome?
146
Cytokinesis in animal cells involves contraction of a ring of ____ microfilaments
actin plus myosin
Cytokinesis in plant cells occurs via the formation of a(n):
cell plate.
Eukaryotic chromosomes are composed of:
chromatin
The microtubules of the mitotic spindle shorten, thus pulling apart the chromosomes by way of ________.
depolymerization
What is the end result of meiosis II in animal cells?
four gametes
A cell in the G2 phase:
has twice the amount of DNA present in a telophase nucleus.
As a cell prepares itself for division, DNA first wraps around what kind of protein to form nucleosomes?
histone
Centrioloes are replicated during the synthesis phase of ________.
interphase
Which is the shortest portion of a cell's life cycle?
M phase
Which characteristic is unique to prophase during meiosis rather than to mitosis?
Paired homologous chromosomes can exchange genetic material.
Chromosomes are duplicated during the ____ of the cell cycle.
S phase
____ contain identical DNA sequences and are held together by ____ during mitosis.
Sister chromatids; cohesin proteins
A cell is dividing by binary fission. What can you conclude?
The cell is prokaryotic
When is a cell in metaphase?
The chromosomes are aligned at the midplane of the cell
What happens to the fragments of the broken down nuclear envelope during prometaphase?
They are sequestered for later use in the daughter cells
What is the purpose of a cell-cycle checkpoint?
To ensure the events of one cell-cycle stage is completed before the next stage begins
To prevent disastrous consequences, the eukaryotic cell cycle is controlled by:
a series of cell cycle checkpoints
Duplicated centrioles move to opposite poles of a dividing ____ cell during the ____ of the cell cycle.
animal; prophase
A new human epithelial cell is an exact copy of its parent cell due to ________.
asexual reproduction
Binary fission is used to replicate what kind of cells?
bacteria
During cytokinesis, plant cells will form a ________ to divide the newly replicated cells
cell plate
During prophase, ____ is(are) compacted into visible chromosomes
chromatin
To control the cell cycle:
cyclins fluctuate during the cell cycle.
Plant hormones known as ____ stimulate mitosis
cytokinins
Plant hormones known as ____ stimulate mitosis.
cytokinins
Nucleosomes are best described as:
eukaryotic DNA associated with histone proteins.
The cell cycle of a The cell cycle of a typical somatic cell consists of the ____ and M phases.
interphase
Microtubules are able Microtubules are able to attach with what region of a chromosome?
kinetochore
At what mitotic phase do chromosomes line up along a cell's equatorial plane?
metaphase
The ____ is responsible The ____ is responsible for the separation of the chromosomes during the ____ of mitosis.
mitotic spindle; anaphase
In a prometaphase cell, the:
nucleolus disappears
The function of nucleosomes is to:
prevent DNA strands from tangling
The purpose of meiosis is to ________.
reduce a diploid to form haploid nuclei
In unwound chromatin, nucleosomes are organized into large coiled loops held together by:
scaffolding proteins
____ organized on chromosomes carry the information that controls the functions of the cell.
Genes
