Bellringer

1. Bellringer Objective 1 Objective 2 Objective 3

2. Objective 1:A sample of digestive juice was removed from the stomach of a pig. The juice was placed in a test tube, along with some grains of wheat.A second,identical test tube that contained an equal number of wheat grains was set up. However, pure water was used rather than digestive juice.

3. The test tubes were kept at 40.0oC for eight hours, which is about the temperature inside a pig's stomach. After eight hours, the grains of wheat in the digestive juice had broken apart into tiny particles. The grains of wheat in the water were wet but were otherwise unchanged.

4. Which of the following statements is supported by the observations made during the experiment described above?A. Water will break down wheat grains after eight hours at 40.0oC .B. Only pigs digest wheat.C. Wheat can be broken down only inside a living organism.D. Wheat will be broken down into small particles by digestive juice

5. The correct answer is D The wheat grains were broken down by the pig’s digestive juices in the test tube, but the water did not break down the grains of wheat.

6. Objective 2: The DNA sequences of a parrot_______. A. are more similar to those of a robin than a clam. B. are more similar to a fern than a dog C. are exactly the same as those of a human D. contain exactly the same nucleotides as those of a beetle

7. The Correct Answer is D. All organisms continue the same nucleotides in their DNA. Adenine, Guanine, Thymine, and Cytosine.

8. What is the main function of the projections on the Human Immunodeficiency Virus?

9. A. They protect the virus and give it its structure. • They aid in respiration. • They help the virus invade its host. • D. They help the virus move and grow.

10. The correct answer is C The envelope proteins on the outside of HIV are specialized to attach to Helper T-Cells, the white blood cells attacked by the viruses.

11. Objective 5 6a and 6b

12. Temperature and Heat • What happens to the temperature of a cup of coffee when left out in a cold room? • The temperature of the coffee will fall until it reaches the air temperature in the room. This is called thermal equilibrium. • The change in temperature is due to the transfer of energy between object and the environment.

13. Temperature & Kinetic Energy • The temperature of a substance will increase if the average kinetic energy of its particles is increased. • KE = ½ mv2 - increase velocity of particles…increase temperature. • If the average kinetic energy of particles decreases, so does the temperature of the substance.

14. Methods of Heat Energy Transfer • Conduction is the transfer of heat energy • between particles of objects in direct contact (solids) • Convection is the transfer of heat energy by • the movement of fluids (gas or liquid) • convection currents due to hot fluid rising and cold fluid sinking • Radiation is the transfer of heat energy as • electromagnetic waves • requires neither contact or mass flow

15. Heat Transfer by Conduction • Conduction is the transfer of thermal energy without any net movement of the material itself. • When a metal poker is put in a hot fire, the exposed end of the poker soon becomes hot as well, even though it is not directly in contact with the source of heat. • Solid materials conduct heat through conduction.

16. Heat Transfer by Convection • Convection is the process of heat transfer through the mass motion or flow of some fluid, such as air or water. • When a pot of water is heated, convection currents are set up as the heated water at the bottom of the pot rises because of its reduced density and is replaced by cooler water from above.

17. Click Play to watch convection currents in the Earth’s Mantle. Earth’s crust moves by Convection Currents in the mantle. Driving Igneous Rocks to the surface where erosion creates Sedimentary Rocks or the moving of the plates creates conditions where Metamorphic Rock can form.

18. Heat Transfer by Radiation Radiation is a more rapid transfer of thermal energy in the form of electromagnetic radiation accomplished by a process that requiresneither contact nor mass flow. A hot object also loses heat energy by radiation. The warmth felt by a fire is due to radiation. If the object is hot enough, some of the radiation is visible and can be indeed seen.

19. What type of heat transfer is shown in the following pictures? B. Radiation A. Convection C. Conduction D. Radiation

20. Phase Changes Heat is gained from the surroundings when a substance melts, evaporates, or sublimes. Heat is given off to the surroundings when a substance freezes or condenses which warms the surroundings.

21. Examples of Uses of Thermal Expansion As water freezes the formation of hydrogen bonds in the ice crystals causes ice to expand.