Answer the following question given this paragraph: Chemical cells are found in batteries. They produce voltage by means of chemical reactions. A chemical cell has two electrodes, which are strips made of different materials, such as zinc and carbon (see Figure below ). The electrodes are suspended in an electrolyte. An electrolyte is a substance containing free ions that can carry electric current. The electrolyte may be either a paste, in which case the cell is called a dry cell, or a liquid, in which case the cell is called a wet cell. Flashlight batteries contain dry cells. Car batteries contain wet cells. Animations at the URL below show how batteries work. Q: Batteries produce voltage through what type of reaction? Choices: - magnetic - radiation - thermal - chemical A:
chemical

Answer the following question given this paragraph: Q: What organs have tiny tubes leading to and from elastic air sacs that improve airflow and oxygen uptake? Choices: - ovaries - apendix - liver - lungs A:
lungs

Answer the following question given this paragraph: Ancestors of mammals evolved close to 300 million years ago. They were amniotes called synapsids. Figure below shows how modern mammals evolved from synapsids. The stages of evolution from synapsids to mammals are described below. Q: How long ago did the ancestors of mammals evolve? Choices: - 10 million - 50,900 million years - 100 million - 300 million years A:
300 million years

Answer the following question given this paragraph: 19.4 Community Ecology Communities include all the different species living in a given area. The variety of these species is referred to as biodiversity. Many organisms have developed defenses against predation and herbivory, including mechanical defenses, warning coloration, and mimicry. Two species cannot exist indefinitely in the same habitat competing directly for the same resources. Species may form symbiotic relationships such as commensalism, mutualism, or parasitism. Community. Q: Commensalism, mutualism, and parasitism are known as what type of relationships? Choices: - simple - peculiar - various - symbiotic A:
symbiotic