*Question*
Answer the following question given this paragraph: Coronary heart disease often does not have any symptoms. A symptom of coronary heart disease is chest pain. Occasional chest pain can happen during times of stress or physical activity. The pain of angina means the heart muscle fibers need more oxygen than they are getting. Most people with coronary heart disease often have no symptoms for many years until they have a heart attack. Q: The pain of angina means the heart muscle fibers need more what? Choices: - water - carbon - nitrogen - oxygen A:
**Answer**
oxygen

*Question*
Answer the following question given this paragraph: The Sun is made mostly of plasma. Plasma is superheated gas with a positive electrical charge. Q: What is defined as superheated gas with a positive electrical charge? Choices: - supernova - greenhouse gas - ion - plasma A:
**Answer**
plasma

*Question*
Answer the following question given this paragraph: 30.3 Roots Roots help to anchor a plant, absorb water and minerals, and serve as storage sites for food. Taproots and fibrous roots are the two main types of root systems. In a taproot system, a main root grows vertically downward with a few lateral roots. Fibrous root systems arise at the base of the stem, where a cluster of roots forms a dense network that is shallower than a taproot. The growing root tip is protected by a root cap. The root tip has three main zones: a zone of cell division (cells are actively dividing), a zone of elongation (cells increase in length), and a zone of maturation (cells differentiate to form different kinds of cells). Root vascular tissue conducts water, minerals, and sugars. In some habitats, the roots of certain plants may be modified to form aerial roots or epiphytic roots. Q: What is the growing root tip protected by? Choices: - root flap - tip cap - root hinge - root cap A:
**Answer**
root cap

*Question*
Answer the following question given this paragraph: Q: Hemolymph bathes organs directly in arthropods and most molluscs, due to an open type of what system? Choices: - nervous - pulmonary - reproductive - circulatory A:
**Answer**
circulatory