Chemical reactions occur when chemical bonds between atoms are formed or broken. The substances that go into a chemical reaction are called the reactants, and the substances produced at the end of the reaction are known as the products.
Answer:
C. Fossils of the winged dinosaur Archaeopteryx show that it had modified scales that produced feathers.
<span>B muscles can only pull
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A type of a balanced stretch involves targeting a specific muscle group. When stretching, a person should be aware of the agonist and antagonist muscles being stretched in able to create a balance between the joints where the muscles are attached. Stretching is an important phase in the exercise cycle and should not be missed as this prevents injuries in the joints and increases the blood flow into the muscles that were used during the activity. Stretching also contributes to lessening the lactic acid build up that happens during physical activity.</span>
Answer:
They maintain their body temperature higher than their environment by some metabolic processes like contraction of muscles, friction produced by flow of blood etc. They have a higher basal metabolic rate, and also a greater capacity to increase their metabolic rate.
