Answer the following question given this paragraph: 2.4 | Inorganic Compounds Essential to Human Functioning By the end of this section, you will be able to: Compare and contrast inorganic and organic compounds Identify the properties of water that make it essential to life Explain the role of salts in body functioning Distinguish between acids and bases, and explain their role in pH Discuss the role of buffers in helping the body maintain pH homeostasis The concepts you have learned so far in this chapter govern all forms of matter, and would work as a foundation for geology as well as biology. This section of the chapter narrows the focus to the chemistry of human life; that is, the compounds important for the body's structure and function. In general, these compounds are either inorganic or organic. An inorganic compound is a substance that does not contain both carbon and hydrogen. A great many inorganic compounds do contain hydrogen atoms, such as water (H2O) and the hydrochloric acid (HCl) produced by your stomach. In contrast, only a handful of inorganic compounds contain carbon atoms. Carbon dioxide (CO2) is one of the few examples. An organic compound, then, is a substance that contains both carbon and hydrogen. Organic compounds are synthesized via covalent bonds within living organisms, including the human body. Recall that carbon and hydrogen are the second and third most abundant elements in your body. You will soon discover how these two elements combine in the foods you eat, in the compounds that make up your body structure, and in the chemicals that fuel your functioning. The following section examines the three groups of inorganic compounds essential to life: water, salts, acids, and bases. Organic compounds are covered later in the chapter. Q: Carbon and what are the second and third most abundant elements in your body? Choices: - helium - mercury - calcium - hydrogen A:
hydrogen
(Question)
Answer the following question given this paragraph: 2.2 Chemical Bonds Each moment of life, atoms of oxygen, carbon, hydrogen, and the other elements of the human body are making and breaking chemical bonds. Ions are charged atoms that form when an atom donates or accepts one or more negatively charged electrons. Cations (ions with a positive charge) are attracted to anions (ions with a negative charge). This attraction is called an ionic bond. In covalent bonds, the participating atoms do not lose or gain electrons, but rather share them. Molecules with nonpolar covalent bonds are electrically balanced, and have a linear three-dimensional shape. Molecules with polar covalent bonds have "poles"regions of weakly positive and negative chargeand have a triangular three-dimensional shape. An atom of oxygen and two atoms of hydrogen form water molecules by means of polar covalent bonds. Hydrogen bonds link hydrogen atoms already participating in polar covalent bonds to anions or electronegative regions of other polar molecules. Hydrogen bonds link water molecules, resulting in the properties of water that are important to living things. Q: Cations are attracted to anions, which are ions with what charge? Choices: - similar - neutral - positive - negative A:
(Answer)
negative
Ques: Answer the following question given this paragraph: Each muscle fiber contains hundreds of organelles called myofibrils . Each myofibril is made up of two types of protein filaments: actin filaments, which are thinner, and myosin filaments, which are thicker. Actin filaments are anchored to structures called Z lines (see Figure below ). The region between two Z lines is called a sarcomere . Within a sarcomere, myosin filaments overlap the actin filaments. The myosin filaments have tiny structures called cross bridges that can attach to actin filaments. Q: Hundreds of organelles called myofibrils, made up of two types of protein filaments, are contained in each fiber of what? Choices: - bone - hair - cartilage - muscle A:
Ans: muscle
(Q).
Answer the following question given this paragraph: The pancreas is a large gland located near the stomach. Hormones secreted by the pancreas include insulin. Insulin helps cells absorb glucose from the blood. It also stimulates the liver to take up and store excess glucose. Q: Which hormone is secreted by the pancreas in a human body? Choices: - growth hormone - progesterone - estrogen - insulin A:
(A).
insulin
Ques:Answer the following question given this paragraph: An electric generator is a device that changes kinetic energy to electrical energy through electromagnetic induction. A simple diagram of an electric generator is shown in Figure below . In a generator, some form of energy is applied to turn a shaft. This causes a coil of wire to rotate between opposite poles of a magnet. Because the coil is rotating in a magnetic field, electric current is generated in the wire. If the diagram in Figure below looks familiar to you, that's because a generator is an electric motor in reverse. Look back at the electric motor in Figure above . If you were to mechanically turn the shaft of the motor (instead of using electromagnetism to turn it), the motor would generate electricity just like an electric generator. You can learn how to make a very simple electric generator by watching the video at the URL below. Making your own generator will help you understand how a generator works. Q: What is a device that changes kinetic energy to electrical energy through electromagnetic induction? Choices: - a battery - a windmill - a diesel engine - an electric generator A:

Ans:an electric generator
Answer the following question given this paragraph: A nonrenewable resource is a natural resource that is consumed or used up faster than it can be made by nature. Two main types of nonrenewable resources are fossil fuels and nuclear power. Fossil fuels , such as petroleum, coal, and natural gas, formed from plant and animal remains over periods from 50 to 350 million years ago. They took millions of years to form. Humans have been consuming fossil fuels for less than 200 years, yet remaining reserves of oil can supply our needs only until around the year 2055. Natural gas can only supply us until around 2085. Coal will last longer, until around the year 2250. That is why it is so important to develop alternate forms of energy, especially for our cars. Today, electric cars are becoming more and more common. What would happen if we ran out of gasoline? Alternative use of energy, especially in transportation, must become a standard feature of all cars and trucks and planes by the middle of the century. Q: A natural resource that is consumed or used up faster than it can be made by nature is termed what? Choices: - renewable - energy-inefficient - fossil fuel - non-renewable A:
non-renewable