Exiting the Cell Cycle - G0
Some cells exist in an inactive stage = G0
Not preparing to divide
Temporary due to environmental conditions, such as a lack of resources
Ex. Seeds
Permanent, such as mature cardiac muscle and nerve cells
Cell Cycle Checkpoints
Checkpoints in the cell cycle regulate cell reproduction
When the checkpoints fail, uncontrolled growth can begin → cancer
Mutation
Mitosis creates exact genetic copies, unless… a mistake in the DNA copy occurs
Creates new alleles
Source of all new genetic variation
Positive, negative, or neutral effects → mutations
Sexual Reproduction
Many eukaryotes can reproduce asexually and sexually
Asexual
Exact genetic copies
Sexual
Combining different alleles = more variation and genetic diversity
More diversity = better chance of long-term survival for a species
Gametes have half the chromosomes = haploid
When they fuse, the zygote is diploid
Some cells exist in an inactive stage = G0
Not preparing to divide
Temporary due to environmental conditions, such as a lack of resources
Ex. Seeds
Permanent, such as mature cardiac muscle and nerve cells
Cell Cycle Checkpoints
Checkpoints in the cell cycle regulate cell reproduction
When the checkpoints fail, uncontrolled growth can begin → cancer
Mutation
Mitosis creates exact genetic copies, unless… a mistake in the DNA copy occurs
Creates new alleles
Source of all new genetic variation
Positive, negative, or neutral effects → mutations
Sexual Reproduction
Many eukaryotes can reproduce asexually and sexually
Asexual
Exact genetic copies
Sexual
Combining different alleles = more variation and genetic diversity
More diversity = better chance of long-term survival for a species
Gametes have half the chromosomes = haploid
When they fuse, the zygote is diploid
