Chemistry of Organisms

Chemistry
All Materials © Cmassengale

Composition of Matter

Ø  Everything in the universe is made of matter

Ø  Matter takes up space & has mass

Ø  Mass is a measure of the amount of matter in the substance

Ø  Mass & weight are NOT the same

Ø  Weight is a measure of the pull of gravity on an object

Question: Is the mass of an object the same on the moon as it is on the Earth? Is its weight the same? (Hint: Gravitational pull on the moon is 1/6 of that on the Earth.)

Ø  Matter exists in 4 states – solid, liquid, gas, & plasma

Ø  Solids have both a definite volume & definite shape (rock)

Ø  Liquids have a definite volume but no definite shape; they can be    poured (water)

Ø  Gases do not have a definite volume or definite shape, but they take the  volume & shape of their container

Ø  Plasmas have no definite volume, no definite shape, and only exist at extremely high temperatures such as the sun

Ø  Chemical Changes in matter are essential to all life processes

Ø  Biologists study chemistry because all living things are made of the same kinds of matter that make up nonliving things

Elements

Ø     Elements are pure substances which cannot be chemically broken down into simpler kinds of matter

Ø     More than 100 elements have been identified, but only about 30 are important in living things

Ø     All of the Elements are arranged on a chart known as the Periodic Table

Ø     Periodic charts tell the atomic number, atomic mass, & chemical symbol for every element

Ø     Four elements, Carbon – C, Hydrogen – H, Oxygen – O, and Nitrogen – N make up almost 90% of the mass of living things

Ø     Every element has a different chemical symbol composed of one to two letters

Ø     Chemical symbols usually come from the first letter or letters of an element like C for Carbon and Cl for Chlorine

Ø     Some chemical symbols come form their Latin or Greek name such as  Na for Sodium (natrium) or K for Potassium (Kalium)

Ø      Elements in the same horizontal period on the periodic table have the same number of energy levels (e.g. H & He in period 1 have only a K energy level)

[Periodic Table]
All Period 2 elements have 2 energy levels
(K & L)

Ø      Elements in the same vertical Family on the periodic table have the same number of electrons in their outermost energy level & react similar (e.g. Family IV, the Carbon family all have 4 electrons in their outermost energy level)

Atoms

Ø     Atoms are the simplest part of an element that keeps all of the element’s properties

Ø     Atoms are too small to be seen so scientists have developed models that show their structure & properties

Ø     Atoms consist of 3 kinds of subatomic particlesprotons & neutrons in the center or nucleus, and electrons spinning in energy levels around the center

Ø     The nucleus is the center of an atom where most of the mass is concentrated

Ø     Protons are positively charged ( p+ ),  have a mass of 1 amu (atomic mass unit) , are found in the nucleus, and determine the atomic number of the element

Example:  Carbon has 6 protons so its atomic number is 6

Ø     Neutrons are neutral or have no electrical charge (n), have a mass of 1 amu, are found in the nucleus, and when added to the number of protons, determine the atomic mass of the element

Example:  Sodium has 11 protons and 12 neutrons so its atomic mass is 11+12=23 amu

Ø     Electrons (e-) are negatively charged, high energy particles with little mass that spin around the nucleus in energy levels

Ø     Seven energy levels (K, L, M, N, O, P, & Q) exist around the nucleus and each holds a certain number of electrons

Ø     The K energy level is closest to the nucleus & only holds 2 electrons, while the  L – Q energy levels can hold 8 electrons  

Ø     Electrons in outer energy level are traveling faster & contain more energy than electrons in inner levels  

Ø     The number of protons (positive charges) and electrons (negative charges in an atom are equal so the net electrical charge on a atom is zero making it electrically neutral

Ø     Stable or non-reactive atoms have an outer energy level that is filled with electrons  

Compounds

Ø     Most elements do not exist by themselves; Most elements combine with other elements

Ø      Compounds are made of atoms of two or more elements chemically combined

Ø      Chemical Formulas represent a compound & show the kind & number of atoms of each element  (e.g. H2O has 2 hydrogen & 1 oxygen)

Ø      Compounds have different physical & chemical properties than the atoms that compose them  (e.g. hydrogen & oxygen are gases but H2O is a liquid)

Ø      The number & arrangement of electrons in an atom determines if it will combine to form compounds

Ø      Chemical reactions occur whenever unstable atoms (outer energy level not filled) combine to form more stable compounds

Ø      Chemical bonds form between atoms during chemical reactions

Types of Chemical Bonds

Ø     Covalent bonds form between atoms whenever they share 1 or more pairs of electrons (e.g. H2O)  

Ø     Molecules form from covalent bonding & are the simplest part of a compound (e.g. NaCl, H2O, O2)  

Ø     Ionic bonding occurs between a positively & negatively charged atom or ion  

Ø     Positively charged ions have more electrons (-) than protons (+); negatively charged ions have more protons than electrons

Ø     Table salt (NaCl) forms when the 1 outer electron of Na is transferred to the outer energy level of chlorine that has 7 electrons (e-)

Ø     Sodium (Na) with 1 less e- becomes positively charged, while Chlorine (Cl) with 1 more e- becomes negatively charged; the + and – charges attract & form the ionic bond holding NaCl together

Ø     Other types of chemical bonding include hydrogen bonding

Energy

Ø     Energy is the ability to do work

Ø     Energy occurs in several forms & may be converted from one form to another

Ø     Sunlight is the ultimate energy for all life on earth

Ø     Forms of energy include chemical, electrical, mechanical, thermal, light, & sound

Ø     Free energy is the energy available for work (e.g. cells have energy to carry out cell processes)

Ø     Cells convert the chemical energy stored in food into other types of energy such as thermal & mechanical

Ø     Energy is used to change matter form one state into another (e.g. liquid into a gas)

Chemical Reactions

Ø     Living things undergo thousands of chemical reactions

Ø     Chemical equations represent chemical reactions

Ø     CO2 + H20—–goes to—–H2CO3  (carbonic acid) is a sample Chemical Reaction in living things

Ø     Reactants are on the left side of the equation, while products are on the right side

Ø Activation energy is required to start many reactions

Ø     Chemical bonds are broken, atoms rearranged, and new bonds form in chemical reaction

Ø     Plants use sunlight to produce sugars such as C6H12O6 glucose; the chemical energy from the sun is stored in the chemical bonds of glucose

Ø      Organisms eat plants, break down the sugars, and release energy along with CO2 & H2O

Ø      Exergonic reactions involve a net release of energy; while endergonic reactions involve a net absorption of energy

Ø      Energy must be added to the reactants for most chemical reactions to occur; called activation energy

Ø      Enzymes are chemical substances in living things that act as catalysts & reduce the amount of activation energy needed

Ø      Organisms contain thousands of different enzymes

Ø      Most enzymes end with –ase (e.g. lipase is the enzyme that acts on lipids)

Reduction-Oxidation (Redox) reactions

Ø     Reactions in which e- are transferred between atoms is a redox or reduction-oxidation reaction (e.g. formation of table salt NaCl)

Ø     In oxidation reactions, a reactant loses 1 or more e- & becomes positively (+) charged (e.g. Sodium atom becomes a Na+ ion)

Ø     In a reduction reaction, a reactant gains 1 or more e- and becomes negatively (-) charged (e.g. Chlorine atom becomes a Cl- ion)

Ø     REDOX reactions always occur together; the electron(s) from the oxidation reaction are then accepted by another substance in the reduction reaction

Solutions

Ø     A large percentage of the mass of organisms is water & many of the chemical reactions of life occur in water

Ø     A solution  is a uniform mixture of one substance in anther

Ø     Solutions may be mixtures of solids, liquids, or gases

Ø     The solute is the substance uniformly dissolved in the solution & may be ions, molecules, or atoms

Ø     The solvent is the substance in which the solute is dissolved

Ø     Water is known as the universal solvent 

Ø     Dissolving one substance in another does not alter their chemical properties

Ø     The concentration of a solution is a measure of the amount of solute dissolved in a given volume of solvent

Ø     Increasing the amount of solute increases the solution’s concentration

Ø     Aqueous solutions are solutions in which water is the solvent; these are important in living things (e.g. blood, cytoplasm of cell…)

Acids and Bases

Ø     The degree of acidity or alkalinity (basic) is important in organisms

Ø     The force of attraction between molecules is so strong that the oxygen atom of one molecule can actually remove the hydrogen from other water molecules; called Dissociation

Ø      H20—–GOES TO—– H+  +  OH-

Ø     OH- called hydroxide ion; H+ called hydrogen ion

Ø     Free H+ ion can react with another water molecule to form H3O+  (hydronium ion)

Ø     Acidity or alkalinity is a measure of the relative amount of H+ and OH- ions dissolved in a solution

Ø     Neutral solutions have an equal number of H+ and OH- ions

Ø     Acids have more H3O+ ions than OH- ions; taste sour; and can be corrosive

Ø     Bases contain more OH- ions than H3O+ ions; taste bitter; & feel slippery  

 

Examples of Common Acids

  • citric acid (from certain fruits and veggies, notably citrus fruits)
  • ascorbic acid (vitamin C, as from certain fruits)
  • vinegar (5% acetic acid)
  • carbonic acid (for carbonation of soft drinks)
  • lactic acid (in buttermilk)
Examples of Common Bases

  • detergents
  • soap
  • lye (NaOH)
  • household ammonia

PH Scale

Ø     Compares the relative concentration of H3O+ ions and OH- ions

Ø     Scale ranges from 0 to 14; 0-3 is very acidic; 7 is neutral; 11-14 is very basic or alkaline

 

Ø    Litmus paper, phenolphthalein, pH paper, & other indicators that change color can be used to measure pH

Buffers

Ø     Control of pH is important to organisms

Ø     Enzymes function only within a narrow pH range; usually neutral

Ø     Buffers neutral acids or bases in organisms to help control pH

Chemistry Study Guide Chemistry On-line

 

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Chapter 2 Worksheet BI – Chemistry

 

Chemistry Worksheet

 

Section  2-1    Composition of Matter  

1. Define matter.

2. Define mass.

3. Explain the difference between mass & weight.

4. Why do biologists study chemistry?

5. Define element.

6. Name the 4 elements that make up 90% of the mass of living things. Give the symbol for each of these elements.

7. Explain why some elements such as sodium have odd symbols.

8. Sketch a block from the periodic table and label the atomic number, atomic mass, & symbol for the element.

9. Define atom and tell whether they can be seen.

10. What is the center of an atom called & what 2 subatomic particles are found there?

11. How does the charge of a proton differ from the charge of a neutron?

12. Where is most of the mass of an atom concentrated?

13. How is the atomic number of an element determined?

14. What is the charge on an electron?

15. Explain why the overall or net charge on an atom is zero.

16. Where are electrons found in an atom & describe their movement?

17. In which energy levels do the electrons have more energy?

18. How many electrons can these energy levels hold   — a. first?        b. second? 

19. Define compound and write a formula for water, carbon dioxide, & sodium chloride (table salt).

20. Do compounds have the same chemical properties as the elements that compose them?

21. When would an atom be chemically stable (not react)?

22. What occurs in a chemical reaction?

23. What is a covalent bond?

24. Define molecule.

25. Give an example of a gas that exists as a molecule.

26. Define ionic bond.

27. What is an ion?

28. Name a compound formed from — a. covalent bonding?            b. ionic bonding?

29. If electrons are shared, a(n) ______________ compound forms.

30. If electrons are transferred, a(n) _____________ compound forms.

31. Forming ionic or covalent bonds helps make atoms more ________________.

Section 2-2    Energy 

32. All living things require _____________ to do work.

33. Energy can’t be created or _____________ in a chemical reaction, but it can be _____________ from one form into another.

34. Name 4 forms of energy important to living things.

35. What is free energy?

36. Give an example of energy changing form in an organism.

37. Atoms & molecules are in constant _______________.

38. Name the 3 main states of matter.

39. Explain how the shape and volume of a solid, liquid, and gas differ.

40. Organisms undergo thousands of ____________ as part of their life processes.

41. Where are the reactants and products in a chemical equation?

42. What does a two-direction arrow mean in a chemical equation?

43. _______________ are broken down in chemical reactions in your body to release ___________ and produce _______________ and ______________.

44. What is the difference between an endergonic & exergonic reaction?

45. What is activation energy?

46. What effect does a catalyst have on activation energy?

47. What are biological catalysts called?

48. Redox is the abbreviation for what type of reaction?

49. Redox reactions involve the transfer of energy and _________ between atoms.

50. What happens during oxidation?

51. What happens during reduction?

52. Give an example of oxidation.

53. Give an example of reduction.

Section 2-3        Solutions   

54. Many of the chemical reactions in organisms take place in __________.

55. What is a solution?

56. Give an example of a complex solution in your body.

57. Name & describe the 2 parts of a solution.

58. What is meant by concentration of the solution?

59. How do you get a saturated solution?

60. What are aqueous solutions?

61. Explain dissociation of water molecules.

62. Name and give the charge for the 2 ions formed whenever water dissociates.

63. Write the final equation for the dissociation of water.

64. What is the hydronium ion?

65. How are acidity and alkalinity measured?

66. When would a solution be neutral?    Give an example of a neutral solution.

67. When would solutions be considered as acidic?

68. Acids have what taste?

69. Acids form what ion in water?

70. Give an example of an acid in your stomach.

71. When would solutions be considered as a base?

72. What adjective refers to basic solutions?

73. Give an example of a base.

74. What ion forms whenever a base is dissolved in water?

75. How does a base taste and feel?

76. How is soap made?

77. What is the pH scale used for?

78. What is the range for the pH scale?

79. At what pH would you find each of these solutions on a pH scale:    a. acids?    b. Bases?    c. neutral?

80. How many times stronger is a pH of 3 than a pH of 5?

81. A change of one pH unit reflects a __________ change.

82. Why is controlling the pH range important to organisms?

83. How do organisms control their pH levels?

84. What is a buffer?

85. Give an example of a human body fluid that is:    a. acidic?    b. alkaline?


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Chapter 30 AP Objectives

 

Chapter 30     Plant Diversity II: The Evolution of Seed Pants
Objectives
Key Terrestrial Adaptations Were Crucial to the
Success of Seed Plants
1. Name five terrestrial adaptations that contributed to the success of seed plants.
2. Compare the size and independence of the gametophytes of bryophytes with those of seed plants.
3. Describe the ovule of a seed plant.
4. Contrast the male gametophytes of bryophytes with those of seed plants.
5. Explain why pollen grains were an important adaptation for successful reproduction on land.
6. Explain how a seed can be said to include contributions from three distinct generations.
7. Compare spores with seeds as dispersal stages in plant life cycles.
Gymnosperms
8. Explain how climatic changes with the formation of the supercontinent Pangaea favored the spread of gymnosperms.
9. List and distinguish among the four phyla of gymnosperms.
10. Describe the life history of a pine. Indicate which structures are part of the gametophyte generation and which are part of the sporophyte generation.
Angiosperms (Flowering Plants)
11. Identify the following floral structures and describe a function for each:

a. sepal f. anther
b. petal g. stigma
c. stamen h. style
d. carpel i. ovary
e. filament j. ovule
12. Define fruit. Explain how fruits may be adapted to disperse seeds.
13. Explain why a cereal grain is a fruit rather than a seed.
14. Diagram the generalized life cycle of an angiosperm. Indicate which structures are part of the gametophyte generation and which are part of the sporophyte generation.
15. Describe the role of the generative cell and the tube cell within the angiosperm pollen grain.
16. Explain the process and function of double fertilization.
17. Explain the significance of Archaefructus.
18. Explain the significance of Amborella.
19. Distinguish between monocots and eudicots.
20. Explain how animals may have influenced the evolution of terrestrial plants and vice versa.
Plants and Human Welfare
21. Name the six angiosperms that are most important in the diet of the human species.
22. Describe the current threat to plant diversity caused by human population growth.

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Chapter 1 Worksheet BI

 

Biology – Science of Life

 

Section 1-1            Themes of Biology 

1. How many species of organisms are estimated to inhabit the Earth? 

2. About how many species have actually been identified? 

3. When did the first life forms probably arise on Earth? 

4. What was the first organism like? 

5.  What is an organism? 

6. Most unicellular organisms can only be seen with a __________________________.

7. Where did these first cells live? 

8. Over time, organisms _____________ and new kinds of _______________ arose from ___________ of organisms and came to inhabit every _______________ of the Earth. 

9. Define biology. 

10. Name several things that the study of biology would include. 

11. The study of biology is unified by ___________________________. 

12. Name 6 unifying themes of biology. 

13. What is a cell? Where are they found? 

14. What is the difference between a unicellular & a multicellular organism? 

15. Cells are ___________________ but highly _______________________.

16. Are all cells alike? Explain. 

17. All cells are surrounded by a ____________ & contain _____________  instructions. 

18. Genetic instructions are used by cells to make new __________ and new cell ________________. 

19. How do new cells produced by unicellular organisms compare to the parent unicellular organism? 

20. How do mature multicellular organisms begin their life? 

21. If multicellular organisms begin their life as one cell, how do they have so many cells? Explain. 

22. Give an example of an organism maintaining a stable internal environment. 

23. Define homeostasis and tell whether it occurs in unicellular&/or multicellular organisms. 

24. Genetic information is passed to offspring during _______________________.

25. What molecule contains the cell’s hereditary information?

26.  How does DNA exist in multicellular organisms? In unicellular organisms? 

27. What is a gene?

28. In multicellular organisms, each body cell has an _____________ copy of its DNA.

29. Does each cell in a multicellular organism use all the genes on its DNA? Explain. 

30. Explain sexual reproduction. 

31. When a sperm joins with an egg to make a fertilized cell, what happens next to this cell? 

32. New organisms from sexual reproduction have _______________ material from both parents.

33. Explain asexual reproduction. 

34. Name a unicellular organism that reproduces by asexual reproduction.

35. New cells or organisms from asexual reproduction have ____________ genetic information. 

36. What is evolution? 

37. Do individuals or populations evolve? 

38. What is the driving force for evolution? 

39. Explain natural selection and give an example. 

40. Competition for what types of resources drives natural selection? 

41. Why is it so important to a species for members to survive? 

42. Organisms that survive and reproduce are ones with ________________ traits.

43. Define ecology. 

44. What are ecosystems and give an example? 

45. Name 3 things organisms must get from the environment to survive. 

46. What has been the effect of man’s activities on many ecosystems? 

47. Living things are _______________ and need a constant supply of _________________.

48. What process supplies energy for organisms on Earth? 

49. Define autotroph. 

50. Autotrophs trap _________ and use this energy to combine __________ and  _________ into__________ and starches. 

51. Define heterotrophs. 

52. Give an example of an autotroph.

53. Give several examples of heterotrophs. 

54. How do heterotrophs get their food? 

Section 1-2            World of Biology 

55. List 6 characteristics shared by all living things. 

56. All living things composed of  _________________.

57. Cells may be specialized in _________________ organisms. What does this mean?

58. What is always true about cell size?

59. Living things are organized at what 2 levels?

60. How are cells organized in multicellular organisms?

61. Define metabolism. 

62. The energy from metabolism is used for ___________, ___________, and _______________ of organisms. 

63. What is homeostasis and give an example? 

64. Is growth a characteristic of living and nonliving things? Explain.

65. What 2 things must occur for living things to grow?

 

 

66. Define cell division.

 

 

 

67. Define development.

 

 

 

68. Explain why development is necessary for multicellular organisms?

 

 

 

69. Is reproduction essential to the survival of a species? Explain.

 

 

 

70. Sexual reproduction produces offspring ______________________ to the parents.

 

71. Have all organisms been identified? Explain.

 

 

Section 1-3            Scientific Method

 

72. Scientists solve problems using the ___________________________.

 

73. The first step of the scientific method is when scientists make ___________________ of the natural world.

74. Define data.

 

 

 

75. What does a scientist usually employ in making their observations?

 

 

76. What is quantitative data?

 

77. What is sampling & why is it used by scientists?

 

 

 

78. What 2 things must be true for samples to be useful?

 

 

79. To be useful, data must be _____________________ into ____________________,

 

       ______________________, and _____________________, or maps.

 

80. Once an observation is made, the second thing a scientist must do is to develop a(n) ___________________________.

 

81. Define hypothesis.

 

 

 

82. All hypotheses must be __________________ to give supporting evidence.

 

83. What is a prediction & how are they usually written?

 

 

 

84. What is an experiment?

 

 

 

85. Name the 2 groups in a controlled experiment.

 

 

86. Both groups in an experiment are identical except for ___________ factor called the

 

       ___________________.

87. Name the 2 types of variables in a controlled experiment.

 

 

 

88. After data is collected and organized, it must be __________________ to tell if it is reliable.

 

89. If experimental data does not support the hypothesis, what should be done?

 

 

90. What is a scientific model?

 

 

91. What is an inference?

 

 

 

92. How is a theory formed?

 

 

93. Define theory.

 

 

94. What is the difference between a field biologist and a laboratory biologist? Do they both use the scientific method?

 

 

 

 

95. What do scientists do with the results of their scientific studies?

 

 

 

Section 1-4            Microscopes & Measurement

 

96. What is a microscope?

 

 

97. What is the difference between resolution & magnification?

 

 

 

 

98. When would a microscope be used?

 

 

99. Do all microscopes have the same magnification & resolution?

 

100.  Draw and label the parts of a light (LM) microscope.

 

 

 

 

 

 

 

 

 

101. Tell the function of each of these parts of an LM — stage, light source, objective lens, ocular lens, & nosepiece.

 

 

 

 

 

 

102. To view specimens with a light microscope, they must be placed on a _______________

 

         and be ________________ so light will pass through to the lenses & your eyes.

 

103. What is the power of magnification & explain how it is determined?

 

 

 

104. Light microscopes can only magnify up to ______________ before the image becomes blurry.

105. What type of scope is used to view viruses & cell parts?

 

106. What produces an image with the electron microscope?

 

 

107. Name the 2 main types of electron microscopes.

 

108. What is the highest magnification for the TEM? For the SEM?

 

 

109. Can electron microscopes be used to view living cells?

 

110. What type of scope gives a magnified view of an object’s surface?

 

111. What is the standard unit of measurement used by scientists?

 

112. Name the SI base units, what they measure, & give their abbreviations (table 1-1, page 23)

 

 

 

 

 

 

113. The SI system is based on units of __________ with designated _________________.

 

114. Give the SI prefix for these base units — 1000, .01, .001, .000001, .000000001, & .000000000001.

 

 

 

 

 

115. Give the SI unit for area, volume, and time.

 

 

Chapter 31 AP Objectives

 

Chapter 31     Fungi
Objectives
Introduction to the Fungi
1. List the characteristics that distinguish fungi from members of other multicellular kingdoms.
2. Explain how fungi acquire their nutrients.
3. Describe the basic body plan of a fungus.
4. Describe the processes of plasmogamy and karyogamy in fungi.
5. Explain the significance of heterokaryotic stages in fungal life cycles.
Diversity of Fungi
6. Describe the evidence that suggests that Fungi and Animalia are sister kingdoms.
7. Explain the possible significance of the flagellated spores of members of the phylum Chytridiomycota.
8. Describe the life cycle of the black bread mold, Rhizopus stolonifer.
9. Describe two alternate hypotheses to explain the reduced mitochondria of the microsporidia.
10. Distinguish between ectomycorrhizae and endomycorrhizae.
11. Distinguish among the Zygomycota, Ascomycota, and Basidiomycota. Include a description of the sexual structure that characterizes each group and list some common examples of each group.
Ecological Impacts of Fungi
12. Describe some of the roles of fungi in ecosystems.
13. Describe the structure of a lichen. Explain the roles of the fungal component of the lichen.
14. Explain how lichens may act as pioneers on newly burned soil or volcanic rock.
15. Describe the role of fungi as agricultural pests.
16. Define mycosis, and describe some human mycoses.
17. Describe three commercial roles played by fungi.
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