cancer and cell cycle Flashcards
name the 3 main checkpoints
G1 => S
G2 => Mitosis
Metaphase => Anaphase
G1 => S
is the cell big enough?
G2 => Mitosis
is DNA replicated?
Metaphase => Anaphase
are chromosomes aligned?
at each checkpoint, ______ acts as “stop signs”
specialized proteins
name 4 reasons cell division will not occur
cells of that type are not required
not enough nutrients for cell growth
DNA has not replicated
DNA is damaged
cell division is needed to replace _______ and _______ cells
damaged / worn out
when cells leave at the first checkpoint, what cycle do they enter?
non dividing stage
how many cells die in the human body per minute?
3 billion
what are 2 types of cell death?
apoptosis
necrosis
why do cells leave the cell cycle?
it’s time to die
what is apoptosis?
programmed cell death
what kills the cell (apoptosis)?
“suicide genes”
cells can only divide a certain number of times until they _________
receive instructions to die
what is a major purpose of apoptosis?
to remove cells that have lost their ability to function correctly
what is necrosis?
cell death due to unexpected and accidental cell damage
what are some reasons cells might be damaged beyond repair?
toxic chemicals (radiation, toxins) physical events (trauma, lack of oxygen due to blocked blood flow)
what happens when a cell ignores the “stop signs”?
they don’t leave the cell cycle to die, but continue to grow and divide repeatedly and excessively to create a lump of abnormal cells
what is the lump of abnormal cells called?
a tumour
what happens when a tumour is further mutated?
it can become cancerous
what is cancer?
a group of diseases in which cells with abnormal DNA are growing and dividing uncontrollably and can spread to other body parts
how can cancer change DNA?
exposure to carcinogens
inherited genes
what is a carcinogen?
agents that can cause DNA mutation
name 3 carcinogens and examples
viruses (HPV, Hepatitis B)
radiation (UV rays, X rays)
chemicals (tobacco smoke)
what is a tumour?
an abnormal group of cells that reduces the normal functions of other body tissues by “invading” it
what is a benign tumour?
a non cancerous tumour – does not spread to other tissue
what is a malignant tumour?
a cancerous tumour – can break away from original tumour to a different body part
which type of tumour can grow large and crowds nearby cells and affect normal functions?
benign
which tumour interferes with functions of nearby cells and may destroy other tissue?
malignant
what is metastasis?
cancer cells can break away from the original tumour and move to a different part of the body
what happens if cancer cells settle in another part of the body?
they will continue to grow and divide uncontrollably and can start a new tumour
name 5 major types of cancer
carcinoma sarcoma leukaemia myeloma lymphoma
what type of cancer is carcinoma?
epithelial cells (skin/surface of internal organs)
what type of cancer is sarcoma?
muscle, bone, cartilage, other connective tissue
what type of cancer is leukaemia?
bone marrow (white blood cells)
what type of cancer is myeloma?
white blood cells producing antibodies
what type of cancer is lymphoma?
immune system cells
name 3 common cancer treatments
radiation therapy
chemotherapy
surgery
what is radiation therapy?
using radiation to kill cancer cells
what is chemotherapy?
taking chemical drugs
what is surgery?
removing the tumour
name an advantage of radiation therapy
useful when surgery cannot be carried out
name an advantage of chemotherapy
slows or controls spread of cancer
name an advantage of surgery
if found early, tumour can be removed
name 2 disadvantages of radiation therapy
can damage normal cells
side effects: nausea, vomiting, skin redness or skin pain
name 2 disadvantages of chemotherapy
toxic to normal cells
painful side effects: feeling weak and sick, hair loss
name 2 disadvantages of surgery
may not be possible if cancer has spread
painful recovery
name 2 lesser known cancer treatments
biological therapy
biophotonics
what is biological therapy?
giving chemicals (“cancer vaccines”) to help your immune system fight cancer
what are 3 ways biological therapy stops cancer?
stops / slows cancer cell growth
makes it easier for your immune system to destroy cancer cells
keeps cancer from spreading
what is biophotonics?
when light shines on cells, particles of light are scattered by atoms and molecules of the cells; special devices record these scatter patterns
what are 3 advantages of biophotonics?
allows early detection
fewer side effects
targets cancerous tissues more accurately
