Unit 2 - Cells. Guiding Questions: How do organisms obtain and use energy they need to live and grow? (Chapters 6/8)

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2 Unit 2 - Cells Guiding Questions: How do organisms obtain and use energy they need to live and grow? (Chapters 6/8) How do the structures of organisms enable life s functions? (Chapters 7,9,12)

3 NGSS Standards HS-LS1-6. Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements to form amino acids and/or other large carbon-based molecules. HS-LS1-7. Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy. HS-LS2-3. Construct and revise an explanation based on evidence for the cycling of matter and flow of energy in aerobic and anaerobic conditions.

4 Biblical Integration By faith we understand that the worlds were prepared by the word of God, so that what is seen was not made out of things which are visible. (Hebrews 11:3) "For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him. He is before all things, and in him all things hold together." (Colossians 1:16-17). [Emphasis Added]

5 Matter: the stuff of the universe anything with mass that takes up space Energy: capacity to do work Brainstorm: How do you get energy to move, live and grow? In groups of 3-4 create a diagram (pictures and words) to answer above question. Biochemistry trailer Cell size and scale Copyright Pearson Prentice Hall

6 I. Atoms MIT video Chemistry of Life What are the basic building blocks of living things? A. Basic building blocks of matter B. Smallest particle of an element Example: The element gold is made up of all gold atoms C. Subatomic particles 1. nucleus contains protons and neutrons (mass of atom) 2. surrounded by cloud of electrons (used to form chemical bonds between atoms) Copyright Pearson Prentice Hall

7 Atoms The subatomic particles in a helium atom. # Protons? 2 # Neutrons? 2 # Electrons? 2 Atom s Mass = p + n Atom s Charge? p + + e - Copyright Pearson Prentice Hall

8 Atom Fun Facts: *Placed side by side, 100 million atoms would make a row only about 1 centimeter long. *Atoms contain subatomic particles that are even smaller

9 Carbon Atom Found in almost ALL biological molecules. Identify the number of protons, neutrons and electrons Brainstorm which elements (types of atoms) are most common in living things?

10 6 most common elements in living things

11 Periodic Table All the different types of atoms

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13 6.1 Atoms, Elements, and Compounds Electrons are negatively charged particles that are located outside the nucleus.

14 6.1 Atoms, Elements, and Compounds Elements An element is a pure substance that cannot be broken down into other substances by physical or chemical means. There are over 100 known elements, 92 of which occur naturally. Each element has a unique name and symbol.

15 6.1 Atoms, Elements, and Compounds The Periodic Table of Elements Horizontal rows are called periods. Vertical columns are called groups.

16 6.1 Atoms, Elements, and Compounds Isotopes Atoms of the same element that have the same number of protons and electrons but have a different number of neutrons

17 6.1 Atoms, Elements, and Compounds Radioactive Isotopes When a nucleus breaks apart, it gives off radiation that can be detected and used for many applications.

18 6.1 Atoms, Elements, and Compounds Compounds A pure substance formed when two or more different elements combine Compounds are always formed from a specific combination of elements in a fixed ratio. Compounds cannot be broken down into simpler compounds or elements by physical means.

19 6.1 Atoms, Elements, and Compounds Chemical Bonds Covalent bonds Chemical bond that forms when electrons are shared A molecule is a compound in which the atoms are held together by covalent bonds.

20 6.1 Atoms, Elements, and Compounds Ionic Bonds Electrical attraction between two oppositely charged atoms or groups of atoms Ionic Bonds

21 6.1 Atoms, Elements, and Compounds Some atoms tend to donate or accept electrons more easily than other atoms. The elements identified as metals tend to donate electrons. The elements identified as nonmetals tend to accept electrons.

22 6.1 Atoms, Elements, and Compounds Most ionic compounds are crystalline at room temperature and have higher melting points than molecular compounds formed by covalent bonds.

23 6.1 Atoms, Elements, and Compounds van der Waals Forces When molecules come close together, the attractive forces between slightly positive and negative regions pull on the molecules and hold them together. The strength of the attraction depends on the size of the molecule, its shape, and its ability to attract electrons.

24 Chapter Diagnostic Questions Which of the following particles is negatively charged? A. electron B. isotope C. neutron D. proton 1. A 2. B 3. C 4. D 0% 0% 0% 0% A B C D

25 Chapter Diagnostic Questions Isotopes are created by a change in the number of what particle of an atom? A. electrons B. neutrons C. protons D. ions 1. A 2. B 3. C 4. D 0% 0% 0% 0% A B C D

26 Chapter Diagnostic Questions Identify the proteins that speed up the rate of chemical reactions. A. substrates B. enzymes C. ions D. reactants 1. A 2. B 3. C 4. D 0% 0% 0% 0% A B C D

27 6.1 Formative Questions What particles are in an atom s nucleus? A. neutrons and electrons B. protons and electrons C. protons and neutrons 1. A 2. B 3. C 0% 0% 0% A B C

28 6.1 Formative Questions What causes the overall charge of an atom to be zero? A. an equal number of protons and neutrons B. an equal number of protons and electrons C. an equal number of neutrons and electrons A 1. A 2. B 0% 3. 0% C 0% B C

29 6.1 Formative Questions What type of substance is water? A. a compound B. an element C. an isotope D. a mixture 1. A 2. B 3. C 4. D 0% 0% 0% 0% A B C D

30 6.1 Formative Questions What provides the energy for all living processes? A. chemical bonds B. ionic compounds C. radioactive isotopes D. van der Waals forces 1. A 2. B 3. C 4. D 0% 0% 0% 0% A B C D

31 Chapter Assessment Questions Look at the energy levels in the atom. What is the maximum number of electrons energy level two can hold? A. 2 B. 4 C. 6 D A 2. B 3. C 4. D 0% 0% 0% 0% A B C D

32 Standardized Test Practice Which is a result of van der Waals forces? A. atoms sharing electrons B. table salt dissolving in water C. ionic compounds forming crystals D. water molecules forming droplets A B 1. A 2. B 3. C 4. D 0% 0% 0% 0% C D

33 Vocabulary Section 1 atom nucleus proton neutron electron element isotope compound covalent bond molecule ion ionic bond van der Waals force