24 terms

Cell Cycle

The cell theory states that
All cells come from other living cells
Cell division is used for
Growth, development, maintenance, and repair
division of the nucleus. It is a syncronized set of events that will seperate chromosomes so that the two nuclei formed will be identical
-beginning of cellular division
(Prophase, Metaphase, Anaphase, & Telophase)
Parent cell
original cell inside the organism that will divide
Daughter cell
two identical cells created when the parent cell divides
Sexual reproduction
two seperate organisms produce egg and sperm that must combine or fuse together to produce offspring
process of making egg cells and sperm cells
the fusion of egg and sperm to produce a new organism
Asexual reproduction
offspring are produced by only one individual organism
produced by mold and other fungi that grow all by themselves into more fungi
Binary fission
process of a bacterium splitting in two new bacteria
Cell cycle
defined as of a cell from the beginning of one interphase to the beginning of the next interphase
the growth and development phase of the cell cycle
- three parts
---1) Growth One or G1 phase
---2) Synthesis or S phase ( make DNA)
---3) Growth Two or G2 phase
G1 Phase
-initial growth phase of the cell
-cell grows and carries out its routine functions
-longest phase of interphase
-many cells stop growing and get stuck in this phase for the entire life of the organism
-other cells get stuck in G1 of interphase until cell division is needed for growth or repair
S Phase (synthesis)
-is when DNA replication occurs
-after DNA replication the cell has two complete copies of its DNA
-at this point the cell is committed to dividing
G2 Phase
-the cell continues to grow and the final preparation for cell division are made
Cell Division
the creation of two daughter cells from one parent cell
* each daughter cell will have the same number of chromosomes as the parent cell
------ Two parts of cell division
Mitosis and Cytokinesis
division of the cell cytoplasm. It is the physical seperation of the cytoplasm into two new daughter cells
- end of cell division
- new cells pinch off from each other in animal cells. In plant cells a cell plate is formed, because plants also have cell walls to form.
1) DNA coils & becomes chromosomes
2) Centrioles move to opposite ends of the cell
3) Spindle fibers attach to chromosomes
4) Nuclear membrane breaks down
coiled DNA structures within the nucleus containing genetic information that is passed on from generation to generation
Sister Chromatid
one of the two identical "sister" parts of a duplicated chromosome- formed during S phase
chromosome region that joins 2 sister chromatids
1) Spindle fibers push & pull chromosomes until they line up across center of cell
2) Centromere of each chromosome pair attached to a spindle fiber
1) Spindle fibers shorten & paired chromatids seperate
2) Spindle fibers pull seperated chromosomes to opposite ends of the cell
3) Centromere of each pair divides; now have individual chromosomes