cell cycle and mitosis

How do eukaryotic, prokaryotic cells and viruses replicate

Eukaryotic divide by mitosis or meiosis prokaryotic cells replicate by binary fusion viruses inject their nucleus acid inside their host cells to replicate the virus particles

Cell cycle

interphase (G1, S, G2), nucleic division (mitosis / meiosis), cytokinesis DNA replication occurs during interphase mitosis is when a eukaryotic cell divides to produce 2 daughter cells with identical copies of DNA produced by the parent cell during DNA replication
Cytokinesis division of cytoplasm to create new cells

Describe the stages of mitosis

Prophase - chromosomes condense and become visible (in animal cells, centrioles separate - they create spindle fibres)
Metaphase - chromosomes align in the middle and spindle fibres attach to the centromere and chromatid
Anaphase - spindle fibres pull centromere and chromatids to opposite poles (chromatids are now referred as chromosomes) this stage requires ATP which is provided by respiration in mitochondria
Telophase - nucleus reforms around the chromosomes
Cytokinesis - cytoplasm splints in two to create a genetically identical cells

What can uncontrolled cell division lead to

mitosis is a controlled process so it can lead to formation of tumours or cancers many cancer treatments are directed at controlling the rate of cell division

binary fission

1. Replication of circular DNA and plasmids

2. Division of cytoplasm to produce two daughter cells

How do viruses replicate

• attachment proteins attach to receptors in host cell

• Virus fuses with the host cell and releases DNA into cytoplasm

• Host cell uses viral genetic information to synthesis new viral proteins