Chapter 8; Eukaryotic cell Cycle

S Phase;

DNA replication occurs in preparation for cell division.

Cytokinesis; (C Phase)

the cytoplasm divides, creating two daughter cells.

Eukaryotic cells undergo two different mechanisms to divide up the DNA.

1) Mitosis 2)Meiosis

The Eukaryotic Cell Cycle is divided into distinct phases;

1)Interphase 2)Mitosis 3)Cytokinesis

Eukaryotic cells contain MORE DNA than prokaryotic cells and the DNA is packaged differently.

Cell division in eukaryotic cells is more complex.

Histones; have positive charge to counteract with the negative charges associated with the phosphate groups of the DNA.

DNA is coiled around these proteins.

G2 Phase;

Further preparation for the cell division, including the replication of mitochondria and the synthesis of microtubules.

Interphase is comprised of THREE phases;

G1 Phase S Phase G2 Phase

The Cell Cycle;

Interphase, Prophase (first stage of mitosis), Metaphase, Anaphase, Telophase, Cytokinesis.

Chromosome number varies among organisms.

Most eukaryotes have between 10 and 50 chromosomes in their somatic cells.

Cells that have two of each type of chromosome are called diploid cells= 2n

One chromosome of each pair is inherited from the mother and the other from the father.

Prior to cell division, each of the homologous chromosomes replicates, forming two identical copies called

Sister Chromatids.

The DNA in a chromosome is one very long double-stranded fiber that extends unbroken for the length of the chromosome.

The DNA is coiled in order to allow it to fit in a small space despite being very long.

G1 Phase;

The primary growth phase of the cell following division. Most cells spend a majority of their lifespan here.

Chromosomes are comprised of chromatin, a complex of DNA protein.

There is also some RNA associated with chromosomes.

DNA in eukaryotic cells is linear and packaged into a compact chromosome.

There is more than one chromosome in a eukaryotic cell.

Chromosomes exist as pairs in somatic cells.

These pairs are called Homologous chromosomes or Homologues.

Mitosis; (M Phase)

a microtubular apparatus binds the chromosomes and moves them apart.

Karyotype;

an arrangement of chromosomes.

Homologous Chromosomes

contain information about the same traits but the information may vary.

Mitosis;

is a cell division mechanism that occurs in NON reproductive cells. -These cells are called Somatic Cells.

Meiosis;

is a cell division mechanism that occurs in cells that participate in sexual reproduction. -These cells are called germ line cells OR Gamates

Centromere;

the sister chromatids are joined together by this structure.