question... Brain tumors occur when what is no longer regulated?
Options:
- (A) fossil fuels
- (B) headaches
- (C) voltage
- (D) heat or cold
- (E) cell cycles
- (F) critical organs
- (G) cerebellum
- (H) migraines
answer... Cancer is a disease that occurs when the cell cycle is no longer regulated. Brain tumors are one of the fastest growing cancers today. Brain tumors occur when the cell cycle is no longer regulated.
The answer is (E)

question... Oncogenes promote the division of cells with damaged what?
Options:
- (A) Veins and arteries.
- (B) biological diversity
- (C) Something with a head, thorax, and abdomen
- (D) a hemisphere is tilted away from the sun
- (E) Addition
- (F) Person's genetic fingerprint
- (G) Mathematics division
- (H) Cell phones
answer... Oncogenes promote the division of cells with damaged DNA. DNA DNA DNA is a person's genetic fingerprint. Oncogenes promote the division of cells with damaged parts of a person's genetic fingerprint.
The answer is (F)

question... What feeds on plankton and nonliving organic matter?
Options:
- (A) bacteria
- (B) barnacles
- (C) animals
- (D) sharks
- (E) pythons
- (F) graptolites
- (G) molluscs
- (H) bears
answer...
Bivalves feed on plankton and nonliving organic matter. Bivalve molluscs are very common. Molluscs feed on plankton and nonliving organic matter.
The answer is (G)