Ch 19: Chromosomes and Cell Division
How many chromosomes arranged in how many pairs would be shown in a normal human karyotype?
46, 23
Chromosomes consist of __________.
DNA and protein
What is a likely result if chromatids fail to separate properly during meiosis?
Some of the resulting reproductive cells will have too many copies of certain chromosomes.
Assuming fertilization by a normal sperm, nondisjunction in the female could lead to which of the following?
all of the above
During which phase of mitosis do spindle fibers pull the chromosomes to opposite poles of the cell?
anaphase
Meiosis is called reduction division. When does the reduction in chromosome number occur?
anaphase 1
The new cells (daughter cells) that result from meiosis __________.
are genetically different from their parent cell and also from each other
Cytokinesis is associated with which of the following
both meiosis and mitosis
The membrane of the nucleus __________.
breaks apart and reforms during mitosis
What structure dissolves so that the sister chromatids can move to opposite ends of the cell during cell division?
centromere
What is a specific segment of DNA that directs protein synthesis?
gene
Mitosis happens __________.
in the growth of an embryo
DNA is replicated during __________
interphase
During which phase of the cell cycle does growth occur?
interphase
Which of the following is true regarding interphase?
it is the longest phase of cell divison.
What process in the human life cycle results in the production of gametes?
meiosis
Meiosis happens __________.
only in the creation of sperm and egg cells
The "cell cycle" refers to __________.
the events during the entire life of a cell
The process of crossing over during meiosis involves __________.
the mixing of similar areas of DNA between the chromosomes of an individual in the process of forming sperm or eggs
Independent assortment relates to __________.
the need to randomly select only one chromosome from each pair for a reproductive cell