Chapter 10.2

What are chromosomes?

Packages of genetic information (DNA) bundled together.

What is chromatin?

Complex of DNA.

What is the centromere?

Center of a chromosome.

What are the centrioles?

2 organelles that produce the spindle fibers that pull the chromosomes apart during anaphase.

What is a chromatid?

One half of a duplicated chromosome.

What are spindle fibers?

Fibers that attach to the centromeres and separate chromosomes to opposite sides of the cell.

Describe prokaryotic chromosomes.

Prokaryotes have no nucleus, but they have one circular chromosome in the cytoplasm.

Describe eukaryotic chromosomes.

They are made of chromatin; during cell division, it coils into chromosomes.

What is the Cell Cycle?

A series of events that cells go through as they grow and divide. It begins when the cell is formed and ends when the cell divides.

What is another name for the prokaryotic cell cycle?

Another name for it is "binary fission" (asexual reproduction).

What are the steps for the prokaryotic cell cycle (binary fission)?

First the cell grows; then the DNA doubles; finally it splits in two.

True or false: Eukaryotic cells contain more DNA than prokaryotic cells.

True.

True or false: Eukaryotic cells have chromosomes in the nucleus.

True.

What are ALL the stages of the cell cycle in order?

Interphase, prophase, metaphase, anaphase, telophase, and cytokinesis.

What is interphase?

The period of cell growth in between cell division.

What are the stages of interphase?

G1, S, and G2.

What is the G1 phase of interphase?

Cell growth.

What is the S phase of interphase?

DNA replication; new DNA is synthesized.

What is the G2 phase of interphase?

Preparation for cell division; there is cell growth and organelle production, and the cell is ready to divide.

What is the M phase?

Cell division and the making of 2 daughter cells; very quick compared to interphase.

What are the phases of the M phase?

Mitosis and cytokinesis.

What is mitosis?

The division of the nucleus.

What is cytokinesis?

The division of the cytoplasm; usually occurs at the same time as telophase.

True or false: In eukaryotic cells, the M phase is the only phase where cell division actually occurs.

True.

What are the phases of mitosis in order?

Prophase, metaphase, anaphase, and telophase (PMAT).

What is prophase?

It is the longest phase of mitosis; DNA is duplicated and condenses into chromosomes afterward. Spindles form outside the nucleus produced by centrioles and the nuclear envelope breaks down.

What is metaphase?

It is the shortest part of mitosis; chromosomes line up across the center of the cell and spindle fibers connect each centromere.

What is anaphase?

It is the part of mitosis when chromatids separate and begin to move apart to opposite sides of the cell.

What is telophase?

It is the part of mitosis where the condensed chromosomes begin to spread out into chromatin again; spindles release and the nuclear envelope/nucleolus reform in each daughter nucleus.

Describe cytokinesis in animal cells.

In animal cells, the cell membrane is drawn inward, creating a cleavage furrow. The cytoplasm pinches into 2 parts until the daughter cells separate.

Describe cytokinesis in plant cells.

In plant cells, a cell plate forms between the daughter cells. The cell membrane and cell wall form at the cell plate to separate the cells.