Mitosis, Mutations, and Cancer

General Cancer Definition

unregulated cell division

What is the common cause of cancer?

genetic mutations

Where do you typically find the start of mutations?

genes on chromosomes 

What genes are typically associated with breast cancer?

BRCA1 and BRCA 2

Why do cells divide?

• reproduction

• development

• replacing other cells

• healing wounds

What are the steps of cell division?

• interphase

• mitosis

• cytokinesis

What generally happens during interphase?

growth and preparation (prep)

What generally happens during mitosis?

separate copies of chromosomes (they line up )

What generally happens during cytokinesis?

divide into two cells

When is the last time DNA can be checked and repaired during cell replication?

mitosis

What are the phases of interphase?

• G1

• S

• G2

What does interphase look like?

chromosomes are loosely gathered in the nucleus

G1 Phase

cell grows and makes extra cytoplasm

S Phase

DNA replication occurs, chromosome from identical sister chromatids

G2 phase

cell prepares for division

What changes happen after interphase? 

• “jumbled mess”

• chromosomes are loosely gathered in the nucleus 

Chromatid

one of two identical halves

Inhibition

stopping or pause the cell’s progression 

Prophase

chromosomes begin to coil up

Metaphase

chromosomes align in the middle of the cell

Anaphase 

microtubules shorten, separating sister chroma 

Telophase

daughter cell nuclei are formed 

Cytokinesis

cytoplasm divides and daughter cells are formed. this occurs during the telophase

Chromosomal Perspective

DNA replicates during S phase in interphase

Sister Chromatids 

exact copies of chromosomes that separate during mitosis 

Proto-Oncogenes Gene

accelerators - promote cell division

Tumor Suppressor Gene

breaks - stops the process of division to check it

What are the most common types of mutation?

• point

• frameshift

• rearagnement

Point Mutation

change in protein shape and function

Frameshift Mutation

change in the reading frame of a gene

Rearranged DNA

sections of DNA moved to a different spot

Metastasis

Accumulation