What does a model of the carbon cycle show? The amount of Earth’s carbon increases.

The amount of Earth’s carbon is constant.

The amount of Earth’s carbon decreases.

The amount of Earth’s carbon cannot be determined.

Covalent bonds are formed between metals and boiling points true or false

Match the examples to the correct level of organization. 1. system level roses, snakes, puppies 2. organism level roots, stamens, leaves 3. tissue level bone, cartilage, blood 4. organ level heart, veins, arteries

Which statement describes compounds a. compounds are made of one type of atom. b. compounds cannot be represented by models. c. compounds are represented by chemical formulas. d. compounds cannot be broken down into simpler forms.