NUR 339 Exam 19
- What are the first major phases of the cell cycle?
Answer G1
cell prepares to make DNA S phase DNA synthesis actually takes place G2
prepares for mitosis M phase mitosis occurs 0
resting phase
- In what phase of the cell cycle does mutation typically occur?
Answer S phase
- What are the stages of the cell cycle controlled by?
Answer cyclins (a type of protein), and their inhibitors
- What can defects in the cycle cycle contribute to?
Answer the development of cancer
- Characteristics of benign neoplasms
Answer composed of well differentiated cells that resemble cells of tissues of organ 1 / 3
slow growth rate may become encapsulated usually do not cause death
- Characteristics of malignant neoplasms
Answer cancer atypical cell structure; abnormal nucleus and chromosomes
lose differentiation or resemblance to origin cell (more anaplastic) invade adjacent cells rather than pushing aside more blood supply than normal tissue
- Spread of cancer
- How does cancer metastasize?
Answer direct invasion and extension- local spread, mechanical lysis with enzymes Seeding of CA cells in body cavities
Answer clumps of malignant cells can break off and travel thru blood to a new site(most are killed by the body's defense)
in lymph nodes, cancer may die, grow into mass or remain dormant
- What is a sentinel node?
Answer initial lymph node to which the primary tumor drains
- What is the original tumor called?
Answer primary neoplasm
- What is a metastatic site called?
Answer secondary neoplasm 2 / 3
- What is growth fraction?
Answer ratio of dividing cells divided by G0 cells
- What is doubling time?
Answer time to double total mass of CA cells
- Facts about GF and TD
- What are chemotherapeutic drugs more toxic to?
Answer they are very fast until tumor outgrows blood supply, then slows maybe influenced by hormones
Answer tissues that have a high growth fraction than a low growth fraction
- Proto-oncogenes
Answer normal genes that regulate cell growth and differentiation and are active for only a short time in the cell cycle
- Oncogenes
Answer gene MUTATIONS which become cancer-causing genes; are active continuously and promote unregulated, abnormal and disordered growth
- Oncogenesis
- / 3
Answer Mechanism by which a normal cell is transformed into cancer cell by random genetic mutation or mutation induced by exposure carcinogens