67 terms

Cell Cycle

As a result of mitosis, each resulting cell
recieves and exact copy of all the chromosomes present in the parent cell.
What do the spindle fibers do?
split sister chromatids
The three phases of the cell cycle are (in order):
interphase, mitosis and cytokinesis
T or F: Interphase is a stage of mitosis.
For about what portion of the cell cycle is the cell in interphase?
more than 3/4
What are the stages of mitosis in order?
prophase, metaphase, anaphase and telophase
A cell plate is needed by these cells because they have a rigid outer wall.
Where do chromosomes line up during metaphase?
The stage of the cell cycle in which a cell's DNA is copied is during the ___ phase.
S (synthesis)
What do the centrioles do?
organize microtubules
A cell spends about 90% of the time in the first three phases: First Growth (G1), Synthesis (S) and Second Growth (G2). These collectively are known as
If there are 16 centromeres in a cell, how many chromosomes are there?
The process during cell division in which the nucleus of a cell is divided into two nuclei is called
The longest phase of the cell cycle which is divided into three phases.
The period of Interphase in which chromosomes are replicated.
S phase
During this phase of Mitosis chromotids separate at the centromeres and move to opposite poles.
During this phase of Mitosis chromosomes become visible, centrioles move to opposite sides of the nucleus, and the nuclear envelope breaks down.
What are the new cells that are formed during mitosis called?
daughter cells
The period of Interphase in which cells do most of their growing.
G1 phase
The cell cycle is the
series of events that cells go through as they grow and divide.
The division of the cytoplasm.
Normal human body cells have how many chromosomes?
The period of Interphase in which DNA replication is completed and the cell is ready to begin the process of cell division.
G2 phase
During this phase of Mitosis chromosomes condense and a nuclear envelope reforms around each new cluster of chromosomes.
If a cell has 12 chromosomes, how many chromosomes will each of its daughter cells have after mitosis?
During this phase of Mitosis chromosomes line up across the center of the cell.
T or F: Mitosis is the division of the cell.
False; division of the nucleus
T or F: The duplication of chromosomes (DNA) occurs in prophase of mitosis.
False; s phase of interphase
T or F: Mitosis produces genetically identical cells.
T or F: There are more centomeres than there are chromatids.
False; there are 2 times as many chromatids
T or F: The cell cycle is the process by which eukaryotic cells divide.
In eukaryotic, multicellular organisms, cell division serves as _______.
growth, maintenance and repair for the cell
Transmission of hereditary information is associated with ______.
When a cell with 24 chromosomes divides by mitotic cell division, the resulting offspring cells will each have a maximum chromosome number of ____.
A graduate student was told to use a light microscope to count the number of chromosomes in the cells of a newly discover species. What phase of the cell cycle would the student have to investigate?
M phase
What does G1 stand for and what occurs during this phase?
Gap 1; the cell prepares for DNA synthesis and grows in size
What does S phase stand for and what occurs during this phase?
Synthesis phase; DNA replication
What does G2 stand for and what occurs during this phase?
Gap 2; mitochondria and other organelles divide and more specialized cellular growth occurs
What does M phase stand for and what occurs during this stage?
Mitosis; division of the nuclei and two daughter cells are produced
What occurs during cytokinesis?
cytoplasm divides and the cell plate forms in plants and pinches in animals
How does the sequence of bases on one strand of DNA control the sequence of bases on the second strand?
adenine molecule always pairs with thymine, cytosine always with guanine
DNA helicase is an enzyme that splits the DNA molecule for replication activities. During what phase of the cell cycle would a researcher be able to investigate the activity of the enzyme?
S phase
The replication of a double-strand DNA molecule begins when the strands separate at the _____.
hydrogen bonds between paired nucleotides
Each strand of a chromosome is known a _____.
A biology student was studing various cells under the microscope. She soon noticed that some cells seemed almost to pinch in half during the division. The cells that pinched in half also started to form a membrane before the end of the nuclear division. What type of cells was the student observing?
animal tissue cells
What is the relationship of microtubules to cell division in modern eukaryotic cells?
microtubules form spingle fibers
Sindle fibers attach to chromosomes and appear to _____.
pull them toward the poles
The two chromatids of a chromosome separate from each other during ______.
During cell division, centrioles occupy positions _____.
at opposite poles of the cell
The correct order of events in mitosis is _____.
prophase, metaphase, anaphase, telophase
Replication of the chromosomes (DNA) is eukaryotic cells occurs during _____.
S phase of the cell cycle
The sequence of the cell cycle is _____.
G1, S, G2 mitosis and cytokinesis
T or F: Cytokinesis it alike in plant and animal cells.
T or F: Cytokinesis is the division of the cytoplasm.
T or F: Cytokinesis usually beings around the telophase.
T or F: Cytokinesis is completed in animals when the cell membrane reforms.
During DNA replication, what is (are) the role(s) of DNA polymerases?
connects the nitrogen bases to form new hydrogen bonds and proofreads the DNA molecule, then corrects any errors found
The separation of sister chromatids is called _____.
chromosome segregation
How many chromosomes does every cell in the human body have?
40 in the stomatic cells and 23 in the sex cells
What are the parts of the error correction sequence for newly replicated DNA?
DNA ligase repairs broken DNA strands; "Proofreader" enzymes detect and remove incorrect bases; Enzymes synthesize a replacement sequence
Structures that hold chromatids together in double-stranded chromosomes are known as _____.
The synthesis of a double-stranded chromosome from a single-stranded chromosome is known as _____.
The arrangement of the chromosomes along the equator of the cell occurs during which phase of mitosis?
The disappearance of the nuclear membrane and the nucleoli occurs during which phase of mitosis?
During cytoplasmic division in plants, vesicles form a flat, membrane-bound space across the equatorial plane that is called the _____.
cell plate
What is the name of the enzyme that "unzips" the DNA molecule during replication?
DNA helicase
The sequence of events that occurs in a cell from one mitotic division to the next is called _____.
cell cycle