Reading Essentials for Biology Glencoe (794133), страница 18
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Complete the sentences about water and diffusion with information you learned from yourreading.molecule.b. Water can creep up thin tubes inc. Water resists.changes.d. Waterwhen it freezes.e. Diffusion is the movement of particles from an area ofan area ofconcentration toconcentration.f. The three factors that affect the rate of diffusion are, and,.g. Diffusion allows cells to move substancesandofthe cell.Visit the Glencoe Science Web site at science.glencoe.com to findyour biology book and learn more about water and diffusion.64Chapter 6READING ESSENTIALSCopyright © by Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.a.
Water is aNameDateClassSection6.3 Life Substances◗ Before You ReadSC.G.1.4.3 The student knows that the chemical elements that make up the molecules ofliving things are combined and recombined in different ways. SC.F.1.4.1 The studentknows that the body processes involve specific biochemical reactions governed by biochemical principles. Also covers SC.F.1.4.5This section explains the chemical construction of many of the substances that make up our bodiesand the bodies of other living organisms. What do you think your body is made of? On the linesbelow, list substances that you think make up your body.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________◗ Read to LearnCopyright © by Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.The Role of Carbon in OrganismsCarbon is one of the substances found in living organisms.Carbon atoms can form covalent bonds with other carbon atomsand with many other elements.
When a carbon atom bonds bysharing one electron, it forms a single bond. When it bonds bysharing two electrons, it forms a double bond. When a carbonatom bonds by sharing three electrons, it forms a triple bond.The figure below illustrates the three types of bonds.Molecular Chains As one carbon atom bonds to another and thenthat one bonds to another, they form straight chains, branchedchains, or rings. These chains and rings can contain almost anynumber of carbon atoms and can include atoms of other elementsas well.
The chains and rings are called carbon compounds.Carbon compounds sometimes contain only one or two carbon atoms. But some carbon compounds contain tens, hundreds,or thousands of carbon atoms. These large compounds arecalled biomolecules.State the Main Ideas As youread this section, stop afterevery few paragraphs and putwhat you have just read intoyour own words.Highlight themain idea in each paragraph.Single BondDouble BondREADING ESSENTIALSTriple BondChapter 665NameDateClassSection6.3Life Substances, continuedWhat are examples of biomolecules?Carbohydrates are one type of biomolecule.
Carbohydratesare organic compounds made of carbon, hydrogen, and oxygen.They are used by cells to store and release energy. Starch and________________________sugars are examples of carbohydrates.Lipids are another type of biomolecule. Lipids are large and________________________are made mostly of carbon and hydrogen, with a small amount ofoxygen. Fats, oils, waxes, and steroids are all lipids. Lipids do not________________________dissolve in water because their molecules are not attracted bywater molecules.
Water molecules do not attract lipids becauselipids are nonpolar molecules. Lipids are used by cells for energystorage, insulation, and protective coatings, such as in membranes.Another type of biomolecule is protein. Proteins are necessary2. Analyze DNA is anfor all life because they provide structure for tissues and organsexample of a (Circleand carry out cell metabolism (you learned in Section 6.1 thatyour choice.)metabolism is all of the chemical reactions that occur within ana. nucleic acid.organism).
They provide the body with the ability to move musb. biomolecule.cles. They also are needed to transport oxygen in the bloodstream.c. carbon compound.Proteins are large and complex and are made up of carbon, hydrod. all of the above.gen, oxygen, nitrogen, and sometimes sulfur.Enzymes are a particular typeof protein. Enzymes change theONH2Nspeed of chemical reactionswithin the body.
In some cases,PhosphateNenzymes speed up a reaction thatOSugarwould ordinarily take more time.NitrogenousFor example, enzymes speed upCH2HOPObaseOthe digestion of food.HOA nucleic (noo KLAY ihk) acidis a biomolecule that stores cellular information in the form of aOHOHcode. Nucleic acids are importantcompounds necessary for life.They are made of smaller unitscalled nucleotides.Nucleotides consist of carbon, hydrogen, oxygen, nitrogen, andphosphorus atoms.
These atoms are arranged into three groups: anitrogenous base, a simple sugar, and a phosphate group. The figure above shows the structure of nucleotides. Two importantnucleic acids are deoxyribonucleic acid (DNA) and ribonucleicacid (RNA). DNA is an organism’s master information code. DNAincludes the instructions that determine how an organism looksand acts. RNA forms a copy of DNA to use in making proteins.66Chapter 6READING ESSENTIALSCopyright © by Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.1.
What three elements arecarbohydrates made of?NameDateClassSection6.3Life Substances, continued◗ After You ReadMini Glossarycarbohydrates: organic compounds used by cellsto store and release energy; composed ofcarbon, hydrogen, and oxygenenzyme: type of protein found in all livingthings that changes the speed of chemicalreactionslipids: large organic compounds made mostly ofcarbon and hydrogen with a small amountof oxygen; examples are fats, oils, waxes,and steroids; are insoluble in water and usedby cells for energy storage, insulation, andprotective coatings, such as in membranesnucleic (noo KLAY ihk) acid: complex biomolecules, such as RNA and DNA, that storecellular information in cells in the form ofa codenucleotides: subunits of nucleic acid formedfrom a simple sugar, a phosphate group,and a nitrogenous baseproteins: large, complex biomolecules essentialto all life composed of carbon, hydrogen,oxygen, nitrogen, and sometimes sulfur;provide structure for tissues and organs andhelp carry out cell metabolism1.
Review the terms and their definitions in the Mini Glossary above. Choose two terms thatare related to each other. On the lines below, tell how these terms are related.________________________________________________________________________________________________________________________________________________________________________Copyright © by Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.________________________________________________________________________________________________________________________________________________________________________2.
Complete the diagram with information you learned from reading the section.A.B. LipidsI. BiomoleculesC.1.D.2. RNAVisit the Glencoe Science Web site at science.glencoe.com to findyour biology book and learn more about life substances.READING ESSENTIALSChapter 667NameDateClassSection7.1 The Discovery of Cells◗ Before You ReadSC.H.1.4.5 The student understands that new ideas in science are limited by the context inwhich they are conceived, are often rejected by the scientific establishment, sometimesspring from unexpected findings, and usually grow slowly from many contributors.This section introduces cells. Skim the reading below and find two important facts about cells.Write those two facts in the space below.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________◗ Read to LearnIdentifyScientists Underline eachscientist’s name introducedin this section.
Say the namealoud. Then highlight the sentence that explains the maincontribution the person madeto biology.68Chapter 7The invention of microscopes made it possible for scientiststo view and study cells. Cells are the basic units of living organisms. In the 1600s, Anton van Leeuwenhoek (LAY vun hook)used a single lens microscope to view bacteria, which until thencould not be seen. Later, compound light microscopes usedseveral lenses and could magnify objects up to 1500 times theiroriginal size.The scientist Robert Hooke looked at thin slices of cork undera compound microscope. Thinking the small shapes he saw lookedlike small rooms, he called them cells.By the 1800s, microscopes had been improved, allowing scientists to make other important observations.
First, Robert Brown,a Scottish scientist, discovered that cells had an important innercompartment, the nucleus (NEW klee us). Then, Rudolf Virchowfigured out that the nucleus controls the cell’s activities. Later, twoGerman biologists, Matthias Schleiden and Theodor Schwann,did their own experiments and learned that all living things aremade of one or more cells.READING ESSENTIALSCopyright © by Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.The History of the Cell TheoryNameDateClassSection7.1The Discovery of Cells, continuedWhat is cell theory?The experiments of Schleiden, Schwann, and other scientistsled to the development of what is called the cell theory.
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