Answer the following question given this paragraph: Sex hormones are chemical messengers that control sexual development and reproduction. The male reproductive system consists of structures that produce male gametes called sperm and secrete the male sex hormone testosterone. Q: What are chemical messengers that control sexual development and reproduction? Choices: - lipids - proteins - neurotransmitters - sex hormones A:
sex hormones
Answer the following question given this paragraph: Friction is a force that opposes motion between any surfaces that are touching. Friction can work for or against us. For example, putting sand on an icy sidewalk increases friction so you are less likely to slip. On the other hand, too much friction between moving parts in a car engine can cause the parts to wear out. Other examples of friction are illustrated in the two Figures below and below . You can see an animation showing how friction opposes motion at this URL:. Q: What force opposes a motion of a moving body? for example a car breaking on a road. Choices: - tension - vibration - thermal - friction A:
friction
Q: Answer the following question given this paragraph: Sometimes deep ocean water rises to the surface. This is called upwelling . The figure below shows why it happens ( Figure below ). Strong winds blow surface water away from shore. This allows deeper water to flow to the surface and take its place. Q: What phenomenon occurs when strong winds blow surface water away from shore, allowing deeper water to flow to the surface and take its place? Choices: - percolating - hurricane - tsunami - upwelling A:
A: upwelling
Question: Answer the following question given this paragraph: Muscle tissue consists of cells that can contract, or shorten. Examples include skeletal muscle, which is attached to bones and makes them move. Other types of muscle include cardiac muscle, which makes the heart beat, and smooth muscle, which is found in other internal organs. Q: What kind of muscle is responsible for making the human heart beat? Choices: - deltoid - teres minor - respiratory muscle - cardiac muscle A:
Answer: cardiac muscle
*Question*
Answer the following question given this paragraph: More than one force may act on an object at the same time. In fact, just about all objects on Earth have at least two forces acting on them at all times. One force is gravity, which pulls objects down toward the center of Earth. The other force is an upward force that may be provided by the ground or other surface. Q: How many forces do objects on earth have acting on them at all times? Choices: - ten - three - four - two A:
**Answer**
two
Q: Answer the following question given this paragraph: Q: What do you call a substance that cannot be broken down to other substances by chemical reactions.? Choices: - a participate - a molecule - a compound - an element A:
A: an element