Biology Ch. 10.2
Most - have only one circular strand of DNA.
prokaryotes
Chromosomes in a Prokaryotic Cell:
single, circular strand of DNA
What happens during interphase?
the cell grows, copies its DNA, and prepares for cell division
How does cytokinesis happen in an animal cell?
the cell membrane draws in and pinches off
When do chromosomes make the precise division of DNA?
during cell division
What phase of Mitosis: The chromosomes line up across the center of the cell.
Metaphase
The four stages of Mitosis:
1. Prophase 2. Metaphase 3. Anaphase 4. Telophase
Process of prokaryotic cell cycle:
1. cell grows 2. duplicates its DNA 3. divides by pinching the cell membrane
Process of Interphase:
1. cell grows 2. the cell replicates its DNA 3. the cell produces organelles and materials for division
Process of Eukaryotic cell cycle?
1. cell grows 2. the cell replicates its DNA 3. the cell produces organelles and materials for division 4. the cell divides in two stages- mitosis and cytokinesis
The phases of Interphase...cycle?
1. M phase 2. G1 Phase 3. S phase 4. G2 phase
How do cells divide?
Prokaryotic cells divide by binary fission. Eukaryotic cells divide by a process that includes mitosis, division of the nucleus, and cytokinesis, division of the cytoplasm.
Chromosomes in Eukaryotic Cell:
highly organized structures
The beadlike structures formed by DNA wrapped around - molecules are called nucleosomes.
histone
The first 3 stages of the eukaryotic cell cycle?
interphase
What phase of Mitosis: The chromosomes separate and begin to move to opposite sides of the cell.
Anaphase
sister chromatids seperate and move toward the centrioles
Anaphase
What is the name of the cell division that occurs in the prokaryotic cell cycle?
Binary Fission
When DNA winds around histone proteins
Chromatin
- make possible the precise separation of DNA during cell division.
Chromosomes
what makes the precise division of DNA during cell division possible?
Chromosomes
Chromatin is
DNA wrapped around histone proteins
During prophase, when cell chromosomes become visible, what are the duplicated strands of DNA called? What is the name for the area in which these duplicated strands are joined?
Duplicated strands of chromosomal DNA are called chromatids, and they are joined by a centromere.
In eukaryotic cells, what happens in the G1 phase that differs from the G2 phase?
In the G1 phase, the cell grows. In the G2 phase, the cell gets ready for mitosis.
the duplicated chromosomes line up and spindle fibers connect to the centromes
Metaphase
the division of the nucleus
Mitosis
The eukaryotic cell divides in what two ways?
Mitosis and Cytokinesis
In eukaryotic cells, what are the two main phases of cell division?
Mitosis and cytokinesis
What phase of Mitosis: The chromosomes become visible. The centrioles take up positions on opposite sides of the nucleus.
Prophase
a cell's genetic material condenses, a spindle starts to form, and the nuclear envelope breaks down
Prophase
What phase of Mitosis: A nuclear envelope re-forms around each cluster of chromosomes. The nucleolus becomes visible in each daughter nucleus.
Telophase
the chromosomes begin begin to unwind and a nuclear envelope reforms
Telophase
What is cytokinesis??
The final step of cell division. It completes the M phase of the cell cycle by dividing the cytoplasm of the original cell between the two new cells.
What structures are spindle fibers attached to that help pull the paired chromosomes apart?
The spindle fibers are attached to centrioles toward the poles of the cell, pulling the chromatids apart.
During certain stages of their life cycle, some cells repeatedly undergo mitosis but do not undergo cytokinesis. What would you expect to see if you looked at such cells, or a tissue made up of such cells, under a microscope? Explain your answer.
Under microscopic examination, a tissue whose cells complete all parts of the cell cycle except cytokinesis would appear to be made up of a mass of cytoplasm with many nuclei scattered in it.
How does cytokinesis happen in a plant cell?
a cell plate forms, followed by a new cell membrane, and finally a new cell wall forms
Chromosomes hold what?
a cell's genetic information
the series of events in the growth and division of a cell
cell cycle
In metaphase spindle fibers connect to what?
centromes
In eukaryotic cells, the genetic structure consists of DNA and a tightly wound protein, which together form a substance called -.
chromatin
Cells carry genetic information in packages of DNA called
chromosomes
Packages of DNA
chromosomes
the division of the cytoplasm
cytokinesis
Does division of the cytoplasm differ in animals and plants?
yes
