ANSWERS MARKED A+
✔✔What is the main factor that differentiates cancer cells from normal cells? -
✔✔cancer cells lack *cellular regulation*
(cancer cells were once normal cells but underwent genetic mutations to no longer look,
grow, or function normally, they have lost their cellular regulations)
✔✔What is the feature of *normal cells* in which each normal cell type has a distinct
and recognizable appearance, size, and shape? - ✔✔specific morphology (a feature of
normal cells)
✔✔What is the predictable factor of normal cells in which the nucleus of the cell is small
compared to the rest of the cell, including the cytoplasm? - ✔✔smaller nuclear-to-
cytoplasmic ratio (a feature of normal cells)
✔✔What is the term that means that every normal cell has at least one function that it
performs to contribute to the whole-body function? - ✔✔differentiated function (a feature
of normal cells)
✔✔What occurs because normal cells make proteins that protrude from the
membranes, allowing the cells to bind closely and tightly together? - ✔✔tight adherence
(a feature of normal cells)
*fibronectin* (except for RBCs & WBCs)
*prevents cell wandering from one tissue to the next* (nonmigratory = feature of normal
cells ----> except blood cells)
✔✔What are the two reasons in which normal cells undergo mitosis (cell division)? -
✔✔1. to develop normal tissue
2. to replace lost or damaged normal tissue
✔✔Which phase of the cell cycle do most normal cells spend most of their lives, actively
carrying out their functions but *not dividing*? - ✔✔G0 (reproductive resting state)
✔✔Cellular regulation occurs through proteins that are produced by what? -
✔✔suppressor genes (these proteins control the amount of cyclins present & ensure
that cell division only occurs when it's needed)
(cell division depends on the presence & absence of specific cellular regulation proteins
- *balance between cyclins & suppressor gene products*)
,✔✔What are the proteins that promote cells to enter and complete cell division produce
by & what are they called? - ✔✔produced by *oncogenes* & known as *cyclins*
(activated cyclins allow cells to leave G0 phase and enter the reproductive cycle)
✔✔Explain the different phases of the cell cycle (division). - ✔✔G0 - living cells carrying
out their function but not dividing
G1- cell getting ready for division by taking on extra nutrients, making more energy,
growing extra membrane, increasing cytoplasm
S- DNA synthesis occurs
G2- cell makes important proteins for actual division & in normal physiologic function
after division
M- single cell splits apart into two cells (actual mitosis)
✔✔What feature do normal cells have that inhibit further cell division once a normal cell
is in direct contact on all surface areas with other cells? - ✔✔contact inhibition (cell
division only occurs when some of it's surface is not in direct contact with another cell)
✔✔What is *apoptosis*? - ✔✔feature of normal cells to die at appropriate times in order
to ensure optimum body function
(normal cells have a finite life span)
*ensures that each organ has an adequate number of cells at their functional peak*
✔✔What is the feature of most normal human cells in which cells have *23 pairs of
chromosomes*? - ✔✔euploidy
✔✔What are normal cells *growing in the wrong place or at the wrong time* as a result
of a small problem with cellular regulation? - ✔✔benign tumor cells (*moles, uterine
fibroid tumors, skin tags, endometriosis, nasal polyps*) -
features of benign tumor cells: (same as features of normal cells EXCEPT)
-*cell division*: continuous or inappropriate (instead of none or slow like normal cells)
-*growth*: expansion (instead of well regulated like normal cells)
✔✔What are the ways in which malignant cells differ from normal cells? - ✔✔*malignant
cells are abnormal, serve no useful function, and are harmful to normal body tissues*
-*cell division:* rapid/continuous
,-*appearance:* anaplastic (cell loses specific appearance of parents -- smaller &
rounded , look like other cancer types)
-*nuclear-to-cytoplasmic ratio:* larger
-*differentiated functions*: some or none
-*adherence:* loose (no fibronectin = easily broken off from main tumor)
-*migratory:* yes (*metastasize*)
-*growth:* invasion
-*chromosomes:* aneuploid
-*mitotic index:* high
-*no contact inhibition*
-*no apoptosis*= immortal
(main difference = lack of cellular regulation)
✔✔What is the process of changing a normal cell into a cancer cell? - ✔✔*malignant
transformation*, occurring through a loss of cellular regulation, leading to steps of
*initiation, promotion, progression, and metastasis*
(*carcinogenesis & oncogenesis* = terms for cancer development)
✔✔Describe the first step of carcinogenesis. - ✔✔*initiation:*
-change in gene expression caused by *carcinogens* leading to loss of cellular
regulation
-leads to excessive cell division through DNA damage that results in either loss of
suppressor gene function or an enhancement of oncogene function
-irreversible
-cells becomes cancer if loss of cellular regulation continues
✔✔What are carcinogens? - ✔✔substances that changes the activity of a cell's genes
so that it becomes a cancer cell
-external: chemicals, physical agents, or viruses (responsible for 80% of cancer in US)
✔✔The second step of malignant transformation is *promotion*, describe what happens
in this step. - ✔✔*promotion:*
-enhanced growth of an initiated cell by *promoters* (insulin/estrogen) --> make cells
divide more frequently
-exposure to promoters can shorten latency period & develop into overt tumors quicker
✔✔What is the time between a cell's initiation and the development of an overt tumor? -
✔✔latency period
✔✔What is the 3rd step of malignant transformation, *progression*? - ✔✔*progession*:
-continued change of cancer, making it more malignant over time
, *to become a health problem:*
-tumor develops own *blood supply (angiogenesis)*
-new cells change features from the original, initiated cell & form new groups (*selection
advantages*- allow them to live/divide no matter how surrounding conditions change)
✔✔What is the step of malignant transformation in which *cancer cells move from the
primary location by breaking off the original group & establish remote colonies*? -
✔✔*metastasis* (additional tumors = metastatic or secondary tumors)
-even though the tumor is now in another area, it is still a cancer from the original
altered tissue (primary)
✔✔What is the original tumor, identified by the tissue from which is arose (parent
tissue)? - ✔✔primary tumor
✔✔What is the most common cause of cancer spread? - ✔✔bloodborne metastasis
(cancer cells penetrate blood vessels & spread to distant organs/tissues)
-enzymes created by tumor cells make large pores in the blood vessels for the cells to
enter
✔✔Besides bloodborne metastasis, what is another way that cancer spreads? -
✔✔lymphatic spread
✔✔What are the most common sites of metastasis for *breast cancer*? - ✔✔-*bone*
-*lung*
-liver
-brain
✔✔What are the most common sites of metastasis for *lung cancer*? - ✔✔-*brain*
-bone
-liver
-lymph nodes
-pancreas
✔✔What are the most common sites of metastasis for *colorectal cancer*? - ✔✔-*liver*
-lymph nodes
-adjacent structures
✔✔What are the most common sites of metastasis for *prostate cancer*? - ✔✔-*bone
(especially spine/legs)*
-pelvic nodes
✔✔What are the most common sites of metastasis for *melanoma*? - ✔✔-GI tract
-lymph nodes