Q: Fact 1: Cells that divide uncontrollably may form a tumor, or abnormal mass of cells. Fact 2: For example, a fibroid is a tumor, a wart is a tumor, and cancers are tumors. Given the two facts above, when cells start to divide uncontrollablly, they may form a what? | OPTIONS:
- anemia
- tissue
- fever
- cell
- organ
- fibroid
- acid rain
- illness
A: fibroid

Q: Fact 1: Treating water is used to remove harmful substances before drinking. Fact 2: To ensure that it is safe to drink water, treat it all the time. Given the two facts above, to ensure that water is safe to drink, harmful what are removed before drinking? | OPTIONS:
- leeches
- seeds
- toxins
- currents
- bacteria
- substances
- Roundworms
- plants
A: substances

Q: Fact 1: Antibodies are large, Y-shaped proteins that recognize and bind to antigens. Fact 2: Allergic reactions are caused by substances called antigens. Given the two facts above, allergic reactions can be caused by? | OPTIONS:
- animals
- smoking pipes
- Sulfur dioxide
- Chemical energy
- fur and fat
- antibodies
- smoking tobacco
- Pesticides
A: antibodies

Q: Fact 1: DNA is found in chromosomes. Fact 2: Genes live on chromosomes, chromosomes live in cells. Given the two facts above, where does DNA reside? | OPTIONS:
- membrane
- cells
- embryos
- atom
- complex
- nucleotide
- ligt
- retina
A: cells