seven science

1. 1. I am the powerhouse of the cell. Who am I?
   

• Nucleus

• Vauole

• Mitochondria

• Golgibodies

2. 2. I cover the earth and am essential for life, but I have no color, no taste, and no shape. Who am I?
   

• soil

• land

• water

• air

3.I am the only planet in the solar system where life exists. Who am I?

• Mercury

• Venus

• Earth

• Mars

4. 4.Sound travels faster in air than in water.
   

• True

• False

• may be

• none of these

5.The boiling point of water decreases at higher altitudes.

• True

• False

• may be

• none of these

6.Photosynthesis produces oxygen as a by-product.

• True

• False

• may be

• none of these

7.Which metal is liquid at room temperature?

• Iron

• Mercury

• Copper

• Silver

8.Which part of the plant makes food?

• Root

• Stem

• Leaf

• Flower

9.Which gas do humans exhale during respiration?

• Oxygen

• Carbon dioxide

• Nitrogen

• Hydrogen

10.What is the largest organ in the human body?

• Skin

• heart

• lungs

• stomach