Answer the following question given this paragraph: When ordered by atomic number, the discrepancies within Mendeleev's table disappeared. Tellurium has an atomic number of 52, while iodine has an atomic number of 53. Even though tellurium does indeed have a greater average atomic mass than iodine, it is properly placed before iodine in the periodic table. Mendeleev and Moseley are credited with formulating the modern periodic law , which states that when elements are arranged in order of increasing atomic number, there is a periodic repetition of their chemical and physical properties. We will discuss some of these chemical and physical properties later on in this chapter. The result is the periodic table as we know it today. Q: Even though tellurium does indeed have a greater average atomic mass than iodine, it is properly placed before iodine in the? Choices: - theory table - phases table - cycles table - periodic table A:
periodic table
Answer the following question given this paragraph: Aqua regia, a mixture of nitric acid and hydrochloric acid, is one of the few materials that will dissolve gold. This material, translated to "royal water" in English, was named so because it could dissolve the royal metal gold. First noted in the fourteenth century, aqua regia could be used to help ascertain whether a particular material was actually gold or was some trickery of the alchemist. Nitric acid by itself will not dissolve gold, but will in combination with hydrochloric acid. The chemistry of the process is rather complex, with both acids reacting with the metal to form soluble gold compounds. The gold can be recovered from the solution, making the process useful for purification purposes. Q: What a mixture of nitric acid and hydrochloric acid? Choices: - crystal regia - acidus regia - sulfate regia - aqua regia A:
aqua regia
Q: Answer the following question given this paragraph: Climate is the most important factor in determining the type of soil that forms in a particular area. Q: What is the most important factor in determining the type of soil that forms in a particular area? Choices: - landscape - altitude - migration - climate A:
A: climate
Question: Answer the following question given this paragraph: Polymers are long molecules composed of chains of units called monomers. Q: What long molecules are composed of chains of units called monomers? Choices: - complexes - microbes - drummers - polymers A:
Answer: polymers
*Question*
Answer the following question given this paragraph: 10.4 | Nervous System Control of Muscle Tension By the end of this section, you will be able to: Explain concentric, isotonic, and eccentric contractions Describe the length-tension relationship Describe the three phases of a muscle twitch Define wave summation, tetanus, and treppe To move an object, referred to as load, the sarcomeres in the muscle fibers of the skeletal muscle must shorten. The force generated by the contraction of the muscle (or shortening of the sarcomeres) is called muscle tension. However, muscle tension also is generated when the muscle is contracting against a load that does not move, resulting in two main types of skeletal muscle contractions: isotonic contractions and isometric contractions. In isotonic contractions, where the tension in the muscle stays constant, a load is moved as the length of the muscle changes (shortens). There are two types of isotonic contractions: concentric and eccentric. A concentric contraction involves the muscle shortening to move a load. An example of this is the biceps brachii muscle contracting when a hand weight is brought upward with increasing muscle tension. As the biceps brachii contract, the angle of the elbow joint decreases as the forearm is brought toward the body. Here, the biceps brachii contracts as sarcomeres in its muscle fibers are shortening and cross-bridges form; the myosin heads pull the actin. An eccentric contraction occurs as the muscle tension diminishes and the muscle lengthens. In this case, the hand weight is lowered in a slow and controlled manner as the amount of crossbridges being activated by nervous system stimulation decreases. In this case, as tension is released from the biceps brachii, the angle of the elbow joint increases. Eccentric contractions are also used for movement and balance of the body. An isometric contraction occurs as the muscle produces tension without changing the angle of a skeletal joint. Isometric contractions involve sarcomere shortening and increasing muscle tension, but do not move a... Q: An isometric type of what occurs as the muscle produces tension without changing the angle of a skeletal joint? Choices: - compression - extension - acceleration - contraction A:
**Answer**
contraction
Q: Answer the following question given this paragraph: Figure 35.7 Glial cells support neurons and maintain their environment. Glial cells of the (a) central nervous system include oligodendrocytes, astrocytes, ependymal cells, and microglial cells. Oligodendrocytes form the myelin sheath around axons. Astrocytes provide nutrients to neurons, maintain their extracellular environment, and provide structural support. Microglia scavenge pathogens and dead cells. Ependymal cells produce cerebrospinal fluid that cushions the neurons. Glial cells of the (b) peripheral nervous system include Schwann cells, which form the myelin sheath, and satellite cells, which provide nutrients and structural support to neurons. Q: What is a type of cell that supports neurons and maintains their environment? Choices: - axon cell - neurofilament cell - interneuron cell - glial cell A:
A: glial cell