Which statement describes the condition of the heart at the point indicated in the electrocardiogram?

a. the atria are contracting and pushing blood into the bottom ventricles of the heart.
b. the ventricles are contracting and pushing blood out of the heart to the lungs and body.
c. the valves between the atria and ventricles close, producing the first heartbeat.
d. the valves of the aorta and pulmonary artery close, producing the first heartbeat

Match the following. biodegradable diabetes n hazardous w cancer ozone 1. the layer of the atmosphere that the ozone layer is part of the type of wastes that can be broken down by other organisms into a reusable form the type of solid, liquid, or gas wastes that are toxic, flammable, corrosive, reactive, or radioactive the process by which certain waste materials, such as plastic, glass, aluminum, and paper are prepared for reuse 5. the addictive drug found in tobacco a disease frequently developed by smokers and passive smokers a disease of the pancreas in which insulin is not produced in 7. the correct amounts so that glucose can be converted into energy or stored as fat formed in the atmosphere when chemicals, called volatile 8. organic compounds (vocs), and nitrogen dioxide (no2) are acted upon by sunlight when burned, it can cause an increase of co2, ozone, and sulfur dioxide in the atmosphere stratosphere fossil fuel recycle nicotine