Unit 2 Bio

Uncontrolled cell division

It can be caused by genetic components (ex. inherited gene mutations) or environmental factors (ex. radiation exposure)

by hijacking the body's normal processes

the type of cells or tissues where they originate

skin cancer

Cancer of white blood cells in bone marrow

cancer in the lining of internal organs/skin

Cancer does not discriminate against age, different kinds can appear in all ages.

Testicular and prostate cancer

Ovarian and cervical cancer

Male: 1 in 2 chance
Female: 1 in 3 chance

Maintaining a stable internal environment

relates to branch of biology that deals with the normal functions of living organisms and their parts.

Cancer can disrupt homeostasis by interfering with the body's ability to maintain it. Tumors oxygen and nutrients, depriving nearby tissues, or taking up space in organs so they can't function properly

1. acquire materials/energy
2. respond to their environment
3. reproduce
4. maintain internal environment
5. adapt to environment

1. eukaryotic (animal, plant, fungi)
2. prokaryotic (bacteria)

Contains genetic information of the cell (the "brain" organelle of the cell")

makes proteins from genetic information

produces energy from nutrients

RER: synthesizes proteins
SER: synthesizes lipids and carbohydrates

digests incoming nutrients using enzymes

processing center of the cell

separates cell from surrounding environment, controls what goes in/out of cell

help divide genetic material during cellular reproduction

-distinct
-cells of one type appear the same
-regular shape
-nucleus is smaller and lighter than cancer cell, uniform
-limited number of cell cycles
-telomeres shorten with each division
-eventually undergo apoptosis

nuclear envelope, nucleolus, chromatin, nuclear pores

-double-stranded
-deoxyribose sugar
-phosphate group
-nucleotides TACG
-stable

-single-stranded
-ribose sugar
-phosphate group
-nucleotides UACG
-unstable

nitrogen bases

The sum of all genetic info in a cell

segment of DNA that codes for a protein

the formation of proteins by using information contained in DNA and carried by mRNA

A protein which has a particular role, it is not involved in structure.

a protein that provides structure such as collagen

DNA (transcribes) -> RNA (translates) -> Protein

transcription and translation

inside the nucleus

Genetic info is passed from DNA to RNA using the enzyme RNA polymerase. Results in mRNA

cytoplasm

mRNA moves to a ribosome, where tRNA reads its codons for each corresponding amino acid to bring it into the ribosome. After assembly, the polypeptide is released for use

organized series of events required for cell division

growth, repair, asexual reproduction. it is frequently occurring to replace damaged or old cells.

1. G1: growth occurs as organelles double
2. S: DNA replication occurs as chromosomes duplicate
3. G2: growth occurs as cells prep to divide

1. interphase: DNA replicates and preps for cell division, with a pair of centrioles outside nucleus.
2. prophase: chromosomes are condensing into 2 sister chromatids held together at a centromere. spindle is assembling and nuclear envelope is breaking down.
3. metaphase: nuclear envelope and nucleolus are gone. chromosomes align at spindle equator.
4. anaphase: sister chromatids separate into daughter chromatids. each pole gets a set of daughter chromatids as spindle fibers disassemble.
5. telophase/cytokinesis: spindle disappears, nuclear envelope forms around daughter chromosomes. cleavage furrow is most visible. the 2 nucleus' are identical and the cell divides during cytokinesis

programmed cell death, occurs if cell DNA is unrepairable

division of the cytoplasm to form two separate daughter cells, occurs after telomerase

to regulate the speed a cell is moving through the cell cycle, and to ensure its ready for cell division

1. G1: apoptosis occurs if cell is damaged beyond repair
2. G2: mitosis won't occur unless DNA is replicated
3. M: mitosis stops until chromosomes are properly aligned

cell is simply living and serving its function, not prepping for division

chromosomes

the M phase

Repeated DNA sequences at the ends of eukaryotic chromosomes.

46 (23 pairs)

one from the mother, one from the father

Two chromosomes that are similar in shape/size and carry the same genes. The maternal and paternal members of a chromosome

sister chromatids, centromere, telomeres,

mutations

change in DNA sequence.causes:
•UV light
•Other radiation
•DNA polymerase errors
•Chemical mutagens

Mutated proto-oncogenes that cause cancer. only 1 mutation is needed

Two major types of genes cause cancer

p53, BRCA1

ERBB2, HER 2

-indistinct
-different from surrounding cells
-often irregular shape
-larger nucleus than normal cell
-nucleus varies in size/shape
-nucleus is darker from extra DNA
-are immortal
-active telomerase enzyme repairs telomerase

The spread of cancer cells to locations distant from their original site.

development of new blood vessels

mass of rapidly dividing cells that can damage surrounding tissue

benign:
-localized
-can resemble surrounding tissue
-can be dangerous if they interfere with organ function
malignant:
-can invade other tissue/move locations
-don't resemble surrounding tissue
-present a threat to body

because their telomeres never shorten so they never stop dividing

stage 1 - no spread from origin
stage 2 - spread to nearby tissues
stage 3 - spread to nearby lymph nodes
stage 4 - spread to distant tissues and organs

gets rid of stimulus. body temperature (sweating due to being overheated)

makes stimulus worse to improve condition. childbirth (contractions)

complete blood count (CBC) looks at blood cellsasic blood chemistry.

(gene chips) screen genetic info for doctors to look for mutations/differences between normal and cancerous cells

the process of determining the precise order of nucleotides within a DNA molecule

(polymerase chain reaction) multiple copies of a specific segment of DNA

• Screening mammogram: X-ray of breast/surrounding tissues that looks for abnormalities associated with cancer
• Diagnostic mammogram: x-ray of breast/surrounding tissue, used after finding a lump or suspicious blood work
• Computerized tomography (CT) scans: X-ray of organs with pictures from multiple angles to generate a 3D image
• Positron emission tomography (PET) scan: uses radioactive tracers to measure the metabolism of cells. cancer cells are more active and stand out
• Magnetic resonance imaging (MRI): uses radio waves and magnets to generate detailed images of the body

the use of drugs to treat a disease

targeting the cell cycle to prevent cell division in rapidly dividing cells.

1. Alkylating agents (S phase): chemicals that integrate into the DNA, causing it to break at specific points. Is general and so can cause long-term side effects including other cancers
2. Alkaloids (M phase): chemicals naturally produced by some plants prevent cells from forming spindle fibers, thus preventing cell division
3. Taxanes (M phase): naturally produced and prevent microtubule breakdown during cell division so cell division doesn't continue
4. Antimetabolites (S phase): chemicals that mimic nucleotides, integrated into DNA, interfere with DNA replication, preventing cell division
5. Topoisomerase inhibitors (g2 phase): chemicals that disable topoisomerase enzyme, preventing DNA replication

Radiation is the movement of energy in waves or particles. shorter the wavelength = more energy present

1. External radiation therapy: uses X-rays or gamma rays to target a specific area of the body.
2. Internal radiation therapy: Small deposits of radioactive material are placed in the body.
3. Systemic radiation treatment: Radioactive substances are injected in blood or ingested in body.

1. Interstitial brachytherapy - seeds placed in direct contact with tumor
2. Intracavitary brachytherapy - seeds placed in nearby body cavities
3. Low-dose treatments - Seeds are left inside patient after treatment.
4. High-dose treatment - Seeds are removed after treatment.

convincing immune system to identify/eliminate "non-self" instead of self

-Involves identifying antigen differences between "self" and cancer cells.
-Cancer vaccines use modified viruses to initiate immune response against cancer cells.
-Monoclonal antibodies can be created to target specific cancer antigens.

targets specific sequences of DNA for removal or replacement