The cost of being multicellular
We are susceptible to our somatic cells losing their identity, escaping the cell cycle, and rapidly dividing
How does a proto-oncogene become an oncogene
It mutates, typically the result of mutagens in the environment
Apoptosis
An orderly process where a cell forms apoptotic bodies known as blebs that are phagocytized by macrophages (white blood cells)
Mitotic spindle
Microtubules that move the chromosome to the center of the cell during mitosis
Cancer
Is a failure of apoptosis in our somatic cells
Vertical and horizontal gene transfer
Vertical gene transfer is the transmission of genetics from parent to offspring. Horizontal gene transfer is the transmission of genes between organisms that aren’t necessarily related
Telomeres
Are repeating segments of DNA at the end of our chromosomes that limit the number of cell divisions of our somatic cells
Cancer isn’t usually inherited because
The chromosomal changes and mutations are usually confined to somatic cells
Human somatic cells are
Differentiated into different tissues. Each cell has 46 total chromosomes with 22 pairs of homologous chromosomes
G1
Happens in interphase. DNA transitions from visible chromosomes to chromatin spread throughout the nucleus
Prokaryotes
Reproduce via binary fission
G0
Nerve cells and neurons can live for 80 years or more in this stage
Benign tumors
Grow but don’t spread
Oncogenes
Are linked to cancer in humans
Centrosome
Organizes the mitotic spindle fiber
Centromere
Links sister chromatids together
Mitosis is important for
Reproduction of our somatic cells for growth, development, and repair
Mitosis
Is when the nuclear material is separated in the eukaryotic cell cycle
Metaphase
Sister chromatids are lined up in the middle of the cell. The mitotic spindle is attached to the kinetochore. The nuclear envelope has been broken up. Centromeres are holding sister chromatids together
S phase
DNA is replicated
