Cancer Biology, Meiosis, and Chromosome Anomalies

Vocabulary flashcards covering the cell cycle, cancer mechanisms, treatments, meiosis, and chromosomal non-disjunction disorders.

Hyperplasia

Increased cell division influenced by mutations in cell cycle control genes.

Proto-oncogenes

Normal genes that regulate the cell cycle, directing cells to divide only when stimulated by a growth factor and receptor combination.

Oncogenes

Mutated proto-oncogenes that motivate the cell to keep dividing continuously without external stimulation.

Tumor Suppressing Proteins

Proteins in normal cells that stop cell division during unfavorable conditions; when mutated, cells override checkpoints without DNA repair or self-destruction.

Contact Inhibition

A mechanism in normal cells that sends chemical messages to prevent cells from growing over one another; cancer cells ignore this signal and pile up.

Transforming Growth Factor Beta

A chemical signal in normal cells that instructs growing cells to stop growing to maintain contact inhibition.

Benign Tumor

A slow-growing, encapsulated, non-invasive tumor that does not metastasize.

Malignant Tumor

A fast-growing, non-capsulated tumor that invades, infiltrates surrounding tissues, and metastasizes throughout the body.

Metastasize

The ability of cancer cells to detach and spread throughout the body.

Angiogenesis

The formation of new blood vessels, triggered in cancer by angiogenic proteins to divert nutrients and $O_2$ toward tumor growth.

Anchorage Dependence

A cellular control mechanism where binding proteins send continuous signals to the nucleus verifying a cell is in its correct area, triggering apoptosis if detached.

Apoptosis

Programmed cell death carried out via specific enzymatic reactions when a normal cell fails checkpoints or lacks proper anchorage.

Telomeres

Protective caps on chromosome ends that shorten with each cell division, functioning as a cellular clock that leads to cell death when worn off.

Telomerase

An enzyme that maintains and rebuilds telomeres; its abnormal activation in cancer cells keeps telomeres long and confers cellular immortality.

Carcinogenesis

The gradual, stepwise development of cancer resulting from the failure of genetic controls due to mutations.

Dysplasia

A change for the worse in cell structure characterized by large, variably shaped nuclei, variation in size and shape, and loss of normal features, indicating a pre-cancerous state.

Targeted Therapies

Cancer treatments that specifically kill cancer cells by exploiting vulnerabilities caused by oncogenes or mutated tumor suppressor genes without harming normal cells.

Immunotherapies

Cancer treatments that stimulate the host's immune system to recognize, find, and attack cancer cells.

Meiosis

A form of cell division that divides one diploid cell ($2n$) into four genetically diverse haploid gametes ($n$), each containing half the genetic material of somatic cells.

Recombination (Crossing Over)

The exchange of genetic material between homologous chromosomes before meiosis 1, ensuring gametes contain genetic information from both maternal and paternal sides.

Independent Assortment

The separation of homologous chromosome pairs based on how they randomly align in the cell during meiosis, creating unique combinations of alleles in gametes.

Non-Disjunction

An error occurring during meiosis 1 or meiosis 2 where chromosomes fail to separate correctly, leading to gametes with too many or too few chromosomes.

Cri du Chat

A chromosomal abnormality caused by a broken tip off chromosome 5, causing multiple congenital abnormalities, CNS impairment in walking and learning, and a malformed larynx affecting speech.

Patau's Syndrome

A chromosomal condition noted as Trisonomy 3 characterized by cleft lip and palate, CNS anomalies affecting cognition and motor development, and polydactyly.

Aneuploidy

A condition in which a cell has an abnormal number of chromosomes, such as seen in trisomies.

Karyotype

A visual profile or display of the chromosomal makeup of an individual's cells used to detect genetic errors.

Down Syndrome (Trisomy 21)

An aneuploidy condition involving an extra chromosome 21, resulting in a wide spectrum of cognitive functioning.

Turner's Syndrome

A sex chromosome non-disjunction disorder in females characterized by an XO genotype or missing fragments of an X chromosome.

Klinefelter's Syndrome

A sex chromosome non-disjunction disorder in males with an XXY chromosomal makeup who produce both male and female proteins.

OY Genotype

A sex chromosome non-disjunction combination lacking an X chromosome that is nonviable and results in death.