Cell Cycle & Cell Division

E.coli

• resides in the colon

• only 1 copy of DNA (haploid)

E.coli duplication

• every 20 min

• attached to cell membrane

• duplicates and separates & cell enlarges

Bacterial Mating/Conjugation

• achieved in bacteria that contains plasmids

  • small circular dsDNA that separates from chromosome

Plasmids can

replicate independently from the bacterial chromosome

F plasmid/fertility plasmids allow for…

mating & gene transfer

Bacteria with F plasmid (donor) will..

encounter a bacteria without F plasmid & establish a cytoplasmic bridge to share

• method of passing antibiotic resistance

Integration

• plasmid into chromosome & when bacteria conjugates, they can pass on chromosomal genes

  • increase genetic variation

Bacteria can pick up

DNA from surroundings

DNA folded into

chromatin

Humans have ____ similar copies of each chromosome

2

• with the exception of se chromosomes

Chromosomes that are similar but not identical

homologous chromosomes

• ex: males with x and y

Chromosomal Bands

Staining patterns allow geneticists to identify areas of abnormalities

Chromatin

• chromosomes during interphase

Mitotic chromosomes

• visible during mitosis (condensed)

Components of chromosomes

• DNA replication origin

• Centromere

• Telomere

DNA replication origin

• a place to start DNA replication, multiple sites