chapter 10 biology Flashcards
A bacterial chromosome consists of:
a circular DNA molecule many times larger than the cell
Eukaryotic chromosomes consists of:
Linear DNA molecules complexed with positively charged his tone proteins
Nucleosomes are best described as:
eukaryotic DNA associated with histone proteins
What is the function of nucleosomes?
To prevent DNA strands from tangling
Nucleosomes are organized into large coiled loops help together by:
The cell cycle of a typical somatic cell consists of _____ and M phase
The M phase of the cell cycle involves two main processes:
mitosis and cytokinesis
One nerve cells become mature, they don't usually undergo cell division. Based on your knowledge of the cell cycle, you would predict that mature nerve cells become arrested in the ______ of the cell cycle.
Chromosomes are duplicated during_______ of the cell cycle.
Which of the following represents the overall sequence of events during mitosis?
Prophase, prometaphase, metaphase,anaphase,telophase
If a cell is in G2:
it Has twice has much DNA found than in telophase nucleus
During prophase,____ is(are) compacted into visible chromosomes.
The ______ is responsible for the separation of the chromosomes during_____ of mitosis.
mitotic spindle; anaphase
_______contain identical DNA sequences and are held together by ________ during mitosis
Sister chromatids: centromeres
The mitotic spindle is made of:
The kinetochore serves which of the following functions?
Kinetochores attach to microtubules during mitosis
All of the following events occur during pro metaphase EXCEPT
the duplicated chromosomes become visible with the light microscope
A cell is in metaphase if:
the chromosomes are aligned at the mid plane of the cell
Duplicated centrioles move to opposite poles of a dividing _____ cell during ____ of the cell cycle
The chromosome makeup of an individual organism is called a:
Chromosomes are condensed to their greatest extent during_____ of mitosis
Cytokinesis in animal cells involves contraction of a ring of ______ microfilaments
actin plus myosin
Cytokinesis in plant cels occurs via the formation of a(n):
If a cell is dividing by binary fission then you know that:
The cell is prokaryotic
To prevent disastrous consequences, the eukaryotic cell cycle is controlled by:
a series of cell cycle checkpoints
Which of the following statements concerning the cell cycle is FALSE?
M-Cdk inhibits mitosis
The correct number of chromosomes is maintained during sexual reproduction by:
meiosis, which reduces the chromosome number by half
Animal cells are stimulated to divided by mitosis by:
If meiosis did not occur in sexually reproducing organisms, then:
chromosome number would double in each generation
What evolutionary advantage is provided by sexual reproduction?
increased genetic diversity
Plant hormones known as_______ stimulate mitosis
Homologous chromsomes undergo synapsis during:
A maternal homologue and a paternal homologue synapse to form:
During which phase does crossing-over occur?
A zygote contains the _______ number of chromosomes
In a human cell at prophase 1, there are_______ tetrads.
An animal with a diploid number of 36 chromosomes will have ______ chromosomes in its gametes and _______ chromosomes in its somatic cells
During prophase 1, each chiasma represents:
a site of crossing over
During which of the following stages of meiosis do the sister chromatids separate?
Which of the following events does not occur in prophase 2?
Formation of chiastma
The sources of genetic variation during meiosis are:
crossing over and the random assortment of maternal and paternal chromosomes
Which of the following events does not occur during meiosis 1?
separation of sister chromatids
Refer to Figure 10-1. Which of the following combinations of letters accurately represents two sister chromatids?
A and C
Refer to Figure 10-1. Which of the following combinations of letters accurately represents two homologous chromatids?
A and D
The formation of female gametes is termed:
which of the following are NOT produced by meiosis?
Refer to figure 10-2. The chromosome complement of item 6 in the life cycle is:
Figure 10-2. The process occurring at arrow 3 in the associated figure is:
Gametophyte plants produce gametes using:
Sporophyte plants produce spores using: