1.

Which of the following form the main components of our body cells? (1 point)

carbohydrates and proteins
fat and phosphorous
proteins and iron
nucleic acids and calcium

2.
Organic compounds always contain______. (1 point)

water
oxygen
nitrogen
carbon

3.
Which of these is a compound? (1 point)

Ca
Mg
Na
H20

4.
Water is such a vital part of an organism’s existence because (1 point)

all the chemical reactions take place in water.
water is used to transport materials.
water acts as an insulator.
all of the above

5.
_______ is an inorganic molecule found in bones. (1 point)

Salt
Calcium
Nucleic acid
Lipids

1.carbohydrates and proteins
2. carbon
3. H20
4. all of the above
5. Calcium