If cells secrete acids and bases to maintain most human enzymes, then cells secrete acids and bases to maintain what?  Answer choices: - Chemical energy  - resistance  - increases a body's strength  - To keep their body heat.  - most human enzymes  - aerobic capacity  - allow growth  - temperature
most human enzymes

If the digestive system breaks food into iron for the body, then what does the digestive system break food into for the body?  Answer choices: - sugar  - fatty  - iron  - lipids  - edible  - liquid  - matter  - Energy
iron

If biceps can only contract, then what can only contract?  Answer choices: - nerves  - Epidermis  - the skin  - strong  - biceps  - Bend  - lungs  - forces
biceps

If carbon may be stored in limestone for million of years, then where might carbon be stored for million of years?  Answer choices: - In sediment  - stomach  - limestone  - refrigerator  - weathering  - loose dirt  - Earth  - body water

limestone