concept 9.1 ap bio: Most cell division results in genetically identical daughter cells

What is the main result of most cell divisions?

Genetically identical daughter cells.

What is the exception to most cell divisions producing genetically identical cells?

Meiosis, which produces gametes (sex cells) with half the number of chromosomes.

What is a genome?

All the DNA in a cell that makes up an organism.

How is DNA organized in eukaryotic cells?

Into chromosomes, which are made of chromatin (DNA + protein).

What is chromatin?

A complex of DNA and protein that makes up chromosomes.

What happens to chromatin during cell division?

It condenses into visible chromosomes.

What are sister chromatids?

Identical copies of a duplicated chromosome connected by a centromere.

What is a centromere?

The region where two sister chromatids are most closely attached.

What happens to sister chromatids during cell division?

They separate and are called individual chromosomes.

What are the two main parts of eukaryotic cell division?

Mitosis and cytokinesis.

What is mitosis?

The division of genetic material in the nucleus.

What is cytokinesis?

The division of the cytoplasm.

How does meiosis differ from mitosis?

Meiosis produces non-identical daughter cells with half as many chromosomes as the parent cell.

What happens to DNA before cell division?

It is replicated (duplicated).

What does "condense" mean in terms of chromosomes?

DNA is tightly packed into a visible structure.

What happens to chromosomes during the S phase of the cell cycle?

They are duplicated, forming sister chromatids.

When do sister chromatids become individual chromosomes?

After they separate during cell division.

Define somatic cells.

Body cells that are diploid, containing two sets of chromosomes.

Define gametes.

Reproductive cells (sperm and eggs) that are haploid, containing one set of chromosomes.

Define centromere.

The region of a chromosome where sister chromatids are most closely attached.

Define genome.

The entire set of DNA in an organism's cells.

What are the two main components of chromatin?

DNA and protein.

What happens to chromosomes during cell division?

They condense, align, and separate into daughter cells.

How does meiosis maintain chromosome number in sexual reproduction?

By reducing the chromosome number in gametes to 23, which restores the diploid number (46) during fertilization.

How many sister chromatids are there after duplication of one chromosome?

Two sister chromatids.

What happens during cytokinesis?

The cytoplasm divides, resulting in two separate daughter cells.

What structures become visible during chromosome condensation?

Chromosomes, as tightly packed chromatin.

At what point does a sister chromatid become a chromosome?

When it separates from its twin during cell division.

Prokaryotic genome

A single DNA molecule.

Eukaryotic genome

Multiple DNA molecules organized into chromosomes.

Chromosome composition

Long DNA molecule with thousands of genes.