I really need help drawing each stage of mitosis for the oni.pdf

I really need help drawing each stage of mitosis for the onion root tip in this. I also need help label
each drawing with these terms: terms: nucleus, nucleolus, chromatin, chromosomes, metaphase
plate, daughter chromosomes, and cell plate. (Not all of these structures will be found in all
stages).
Late prophase Metaphase Anaphase Telophase and cytokinesisLaboratory 14: Mitosis and Cell
Division in onion root tips Cells are the basis for life, and they must reproduce for life to continue.
Cells reproduce by a process called cellular reproduction, or cell division. Cell division occurs in all
living organisms as they grow, repair, and reproduce. Bacteria, the simplest living things,
reproduce by a process called binary fission. In binary fission, the bacterium's single chromosome
is duplicated (replicated), the two chromosomes are separated, and then the plasma membrane
and cell wall grow inward, dividing the cell in two. Higher organisms like animals, plants, and fungi,
have many chromosomes, and have a more complex form of cell division. The chromosomes must
first be replicated (copied) and then they must be divided up into two perfectly identical sets or
groups. Only after production of two identical sets of genetic information can the cell successfully
divide. The formation of two identical sets of genetic information (two separate nuclei) is called
mitosis. The division of the cytoplasm is called cytokinesis. Cell division occurs once during the
"lifetime" of a cell, or what is called the cell cycle. The cell cycle has two phases, which are called
interphase and the mitotic phase. Interphase is a period where little cellular activity can be seen,
and most of a cell's lifetime is spent in this phase. However, in a cell that is preparing to divide,
interphase becomes a time in which the cell's DNA molecules (its chromosomes) are replicated,
the cell increases its supply of proteins, and the number of cellular organelles is increased. The
mitotic phase has two events: mitosis and cytokinesis. Mitosis is the process in which the cell
nucleus and its contents (most importantly the chromosomes) are divided and evenly packaged
into two identical daughter nuclei. During cytokinesis, the cell's cytoplasm is divided in two. When
the mitotic phase ends, there are two identical cells present where only one existed before (pages
179-182, A Guide to the Natural World).The Cell Cycle The term cell cycle is used to describe the
life history of living cells. It consists of interphase and the mitotic phase. Interphase cells that are
going to divide increase their cell contents and replicate their chromosomes. Mitotic cells have
completed interphase and are in the process of forming identical daughter nuclei (mitosis) and
dividing the cell's cytoplasm into two separate cells (cytokinesis). Interphase The cell cycle is
divided into phases, even though it is really a continuous process. Interphase has three phases:
G1, S, and G2. During interphase, DNA, with .

1. I really need help drawing each stage of mitosis for the onion root tip in this. I also need help label
each drawing with these terms: terms: nucleus, nucleolus, chromatin, chromosomes, metaphase
plate, daughter chromosomes, and cell plate. (Not all of these structures will be found in all
stages).
Late prophase Metaphase Anaphase Telophase and cytokinesisLaboratory 14: Mitosis and Cell
Division in onion root tips Cells are the basis for life, and they must reproduce for life to continue.
Cells reproduce by a process called cellular reproduction, or cell division. Cell division occurs in all
living organisms as they grow, repair, and reproduce. Bacteria, the simplest living things,
reproduce by a process called binary fission. In binary fission, the bacterium's single chromosome
is duplicated (replicated), the two chromosomes are separated, and then the plasma membrane
and cell wall grow inward, dividing the cell in two. Higher organisms like animals, plants, and fungi,
have many chromosomes, and have a more complex form of cell division. The chromosomes must
first be replicated (copied) and then they must be divided up into two perfectly identical sets or
groups. Only after production of two identical sets of genetic information can the cell successfully
divide. The formation of two identical sets of genetic information (two separate nuclei) is called
mitosis. The division of the cytoplasm is called cytokinesis. Cell division occurs once during the
"lifetime" of a cell, or what is called the cell cycle. The cell cycle has two phases, which are called
interphase and the mitotic phase. Interphase is a period where little cellular activity can be seen,
and most of a cell's lifetime is spent in this phase. However, in a cell that is preparing to divide,
interphase becomes a time in which the cell's DNA molecules (its chromosomes) are replicated,
the cell increases its supply of proteins, and the number of cellular organelles is increased. The
mitotic phase has two events: mitosis and cytokinesis. Mitosis is the process in which the cell
nucleus and its contents (most importantly the chromosomes) are divided and evenly packaged
into two identical daughter nuclei. During cytokinesis, the cell's cytoplasm is divided in two. When
the mitotic phase ends, there are two identical cells present where only one existed before (pages
179-182, A Guide to the Natural World).The Cell Cycle The term cell cycle is used to describe the
life history of living cells. It consists of interphase and the mitotic phase. Interphase cells that are
going to divide increase their cell contents and replicate their chromosomes. Mitotic cells have
completed interphase and are in the process of forming identical daughter nuclei (mitosis) and
dividing the cell's cytoplasm into two separate cells (cytokinesis). Interphase The cell cycle is
divided into phases, even though it is really a continuous process. Interphase has three phases:
G1, S, and G2. During interphase, DNA, with its chromosomal proteins, exists in a highly uncoiled
state. Thus, when the nuclei are stained, distinct chromosomal structures are not visible. The
chromosomes appear, instead, as a granular material called chromatin within the nucleus. This is
easily seen in onion root cell nuclei. The interphase events, which are described briefly below,
take place at much too small a level to be seen through a microscope. The distinguishing
characteristics of interphase onion cells are a very large nucleus with a "grainy" appearance and
the presence of one or more nucleoli (visible as distinctly stained spheres) within the nucleus. The
G1 phase During G1, (G stands for "gap"), most cells approximately double in size, and their
enzymes and organelles approximately double in number. The S phase During the S phase (S
stands for "synthesis"), the cell's chromosomes are duplicated or replicated. By the end of the S
phase, each chromosome has been replicated. Distinct chromosomes are still not visible during

2. this phase. The DNA molecules are intact but are uncoiled and dispersed. The chromosomes in
this uncoiled state are referred to as chromatin. The G2 phase During the G2 phase, structures
directly involved in cell division are synthesized. Spindle fibers, which are bundles of microtubules,
begin to assemble. These will become attached to chromosomes to guide their movement during
cell division.The mitotic phase The mitotic phase is when "active" cell division begins and ends.
During mitosis, two identical daughter nuclei form within the cell. During cytokinesis, two identical
cells (both with identical daughter nuclei) form by cytoplasmic partitioning. Mitosis is divided into
four stages for description, even though it is a continuous and uninterrupted process. Prophase
The chromosomes are in various degrees of formation, ranging from very long, threadlike
structures to shorter, more distinct entities. The nuclear envelope and the nucleoli are beginning to
disappear, but the "nucleus" will still appear round. In early prophase, tiny spots where the
chromatin has begun to condense are visible within the nucleus. In late prophase, there will be
more and larger spots where the chromatin has condensed, even "thread-like" areas may appear.
Metaphase The mitotic spindle is now complete, although this structure is rarely visible in onion
cells. The sister chromatids (chromosomes) are lined up in the middle of the cell, at a location
called the metaphase plate. In onion cells, the chromosomes are so large that they take up half or
more of the cell. They are held in place by spindle fibers, which are not normally visible in onion
cells. Anaphase The sister chromatids are separated and are pulled to opposite ends of the cell by
the spindle fibers. In this stage, it is possible to see the two distinct sets of daughter chromosomes
within a single cell. Remember that in onion cells the chromosomes are quite large. Telophase
and cytokinesis The chromosomes are in different halves of the dividing cell. They will now begin
to uncoil and change from the densely coiled chromosomes to the loose DNA fibers called
chromatin. The chromosomes will, however, still appear as dark staining masses at this point. This
process is much like the reverse of prophase. As the new daughter nuclei form, the cell is also
undergoing cytokinesis. Cytokinesis is evident in onion cells because a faint (usually greenish)
horizontal line will be seen originating in the middle of the cell, between the two sets of
chromosomes.Lab activity A: Mitosis in onion root tip cells Obtain a microscope slide of onion root
tip mitosis. There are three onion root tips on this slide, which you can see by holding it up to the
light. Examine the slide with the microscope's 10X objective. First note the root cap, a thimble-like
mass of cells that covers the tip of the root. Cells just above the root cap contain dense cytoplasm
and relatively large nuclei. Most of the onion's dividing nuclei and dividing cells will be found just
above the root tip. Change to the 40x objective, look in the region just above the root tip, and find
a cell that does not appear to be dividing; its nucleus will be in interphase. These nuclei are quite
large and will contain chromatin (which is grainy) and one or more nucleoli. Next, locate, observe,
and sketch onion cells in the following stages: interphase, early prophase, late prophase,
metaphase, anaphase, and telophase and cytokinesis. Making labeled drawings Please make
careful drawings of all the stages of mitosis in the spaces provided below. Draw only one cell for
each stage. Make your drawings using the 40X objective lens. Label your drawings, when
appropriate, with one or more of the following terms: nucleus, nucleolus, chromatin,
chromosomes, metaphase plate, daughter chromosomes, and cell plate. (Not all structures will be
found in all stages).Lab 14: Required Labels for Drawings: Interphase: * nucleus *nucleolus (only
required on lab 14) *chromatin Early Prophase: *chromatin/ chromosomes (write it this way as it's

3. transitioning from chromatin to chromosomes *either nucleus or spindle (nucleus is disappearing
and the spindle is forming) Late Prophase: *chromosomes * spindle Metaphase: *metaphase plate
*chromosomes * spindle Anaphase: * spindle *daughter chromosomes Telophase/Cytokinesis: *
nucleus * nucleolus (only required on Lab 14) *cell plate (plant cell only) *chromatin