Unit 01: Cancer Why Biology?

Flashcards covering the fundamentals of cancer biology including terminology, cellular structures, the cell cycle, genetic testing methods, and treatment options based on the lecture material.

Cancer

A disease caused by the inability of the body to control the division of cells, which can be triggered by genetic or environmental factors.

Melanoma

A type of cancer that originates in the skin.

Leukemia

A type of cancer originating from white blood cells in the bone marrow.

Carcinoma

A common form of cancer that originates in the lining of the internal organs or the skin.

Sarcoma

A type of cancer originating in connective tissue, such as bone.

Lymphoma

A type of cancer originating in the cells and tissues of the immune system.

Homeostasis

The body's ability to maintain a constant internal environment, including $pH$, temperature, and blood chemistry.

Nucleus

The organelle that contains the genetic information of the cell.

Ribosomes

Structures within the cell where genetic information is used to manufacture proteins.

Mitochondria

The organelle responsible for converting energy found in nutrients into a form usable by the cell.

Endoplasmic Reticulum (ER)

An organelle involved in the synthesis of proteins (rough ER), lipids (smooth ER), and carbohydrates (smooth ER).

Lysosome

The organelle responsible for the digestion of incoming nutrients.

Golgi Apparatus

The processing center of the cell.

Plasma Membrane

The structure that isolates the cell from its external environment and selectively allows for the passage of materials.

Centrioles

Structures that assist in dividing the genetic material and contents of the cell during cellular reproduction.

Enzymes

Usually protein catalysts for chemical reactions; they have an active site where a substrate binds to produce products.

DNA (deoxyribonucleic acid)

A nucleic acid consisting of nucleotides (a 5-carbon deoxyribose sugar, a phosphate group, and a nitrogen-containing base) that stores genetic information.

Genome

The sum of all genetic information in a cell.

Genes

Units of genetic information that provide instructions for making proteins.

Transcription

The first stage of gene expression where RNA polymerase exposes DNA bases and a copy of mRNA is made (using Uracil instead of Thymine).

Translation

The second stage of gene expression where tRNA reads mRNA codons at a ribosome to assemble a polypeptide chain.

Interphase

The majority of the cell cycle where normal functions occur; it consists of $G_1$ (growth), $S$ (synthesis/DNA replication), and $G_2$ (growth) phases.

M Phase

The portion of the cell cycle where cell division occurs, consisting of mitosis and cytokinesis.

Apoptosis

Programmed cell death that occurs if a cell is not ready for division or cannot repair its DNA.

Telomeres

Repeating sections of nucleotides at the end of chromosomes that shorten with each cell cycle; when too short, the cell undergoes apoptosis.

Sister Chromatid

A copy of a homologous chromosome formed during the $S$ phase and held in place by a centromere.

Prophase

The phase of mitosis where chromosomes condense, the nucleolus disappears, the nuclear envelope breaks down, and the spindle begins to assemble.

Metaphase

The phase of mitosis where chromosomes are aligned at the spindle equator midway between the poles.

Anaphase

The phase of mitosis where sister chromatids separate to become daughter chromosomes and move toward opposite poles.

Telophase

The phase of mitosis where the spindle disappears and new nuclear envelopes form around daughter chromosomes.

Mutations

Any changes to the nucleotide sequence of DNA, which can be caused by carcinogens (chemicals), radiation, or viruses.

Tumor-suppressor Genes

Genes that prevent unregulated cell growth by slowing cell cycle progression and surveying DNA for damage; examples include $p53$ and $BRCA1$.

Proto-oncogenes

Genes that speed up the cell cycle; they become oncogenes when a single mutation causes them to be 'stuck' on.

Telomerase

An enzyme that repairs telomeres, making cancer cells immortal.

Angiogenesis

The process where tumor cells release growth factors that cause capillaries to grow toward the tumor to provide oxygen and nutrients.

Metastasis

The spread of cancer cells to other parts of the body through capillaries or lymphatic vessels.

Polymerase Chain Reaction (PCR)

A technique used to make multiple copies of a specific gene of interest for genetic testing.

DNA Microarrays

Gene chips used to screen for specific mutations or differences in gene expression between normal and cancer cells.

Pharmacogenomics

A branch of pharmacology that uses personalized genetic testing to develop therapies targeting specific cancer-causing alleles.

PET Scan

A Positron Emission Tomography scan that uses radioactive tracers to measure cell metabolism, making active cancer cells visible.

Chemotherapy

The use of drugs, such as alkylating agents or antimetabolites, to target the cell cycle and prevent division in rapidly dividing cells throughout the body.

Taxanes

Chemotherapeutic drugs naturally produced by yew trees that prevent microtubule breakdown during cell division.

Brachytherapy

A form of internal radiation therapy where radioactive seeds are placed in direct contact with a tumor (interstitial) or in nearby body cavities (intracavitary).