4. RESULTADOS Y DISCUSIÓN
4.1 Justificación y vinculación al curriculum
2. ABSOLUTE DA ABSOLUTE DATINGTING
• Determines the actual age of the fossil
• Through radiometric dating, using radioactive isotopes carbon-14 and potassium-40
• Considers the half-life or the time it takes for half of the atoms of the radioactive element to decay
• The decay products of radioactive isotopes are stable atoms.
Take a look at the table below. A living organism has carbon-14. For the amount of Carbon in the organism’s body to become half, it will take about 5,700 years; which is the half-life of carbon-14.
Fill up the remaining data in the table. What is the limit in using carbon-14 as a measure to determine a fossil’s age?
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General Biology 2
Lesson 8.4: History of Life on Earth Lesson 8.4: History of Life on Earth
Content Standard Content Standard
The learners demonstrate understanding of the major events in the history of life on Earth.
Performance Standard Performance Standard The learners shall be able to
• create a personal timeline and compare it with the geologic time scale
• design a poster tracing evolutionary changes in a crop plant (e.g., rice or corn) that occurred through domestication
Learning Competency Learning Competency
The learners describe general features of the history of life on Earth, including generally accepted dates and sequence of the geologic time scale and characteristics (STEM_BIO11/12-IIIc-g-8STEM_BIO11/12-IIIc-g-8)
Specific Learning Outcomes Specific Learning Outcomes
At the end of the lesson, the learners will be able to:
• identify the dates and sequence of the periods in the geologic time scale
• identify the major events in each major period
• describe the characteristics of the major groups of organisms present during a time period
• identify types of fossils and
• describe causes of mass extinctions
60 MINS 60 MINS
LESSON OUTLINE - DAY FOUR
Practice
Practice Creation of Fossils 50
Wrap Up
Wrap Up Clean Up 10
Materials Materials
Visual aids on the geologic time scale; 20 printed pictures of events/
structures/ organisms; computers and internet connection Resources
Resources
(1) Freeman, S. Biological Science. 3rd ed. 2008. California: Pearson Benjamin Cummings. pp. 503-525.
(2) Reece, JB, LA Urry, ML Cain, S Wasserman, PV Minorsky, RB Jackson.
Campbell Biology. 9th ed. 2014. Illinois: Pearson Education Inc. pp.
480-499.
(3) Russell PJ, SL Wolfe, PE Hertz, C Starr, B Mc Millan. Biology: the Dynamic Science. 2008. California: Brooks/Cole CENGAGE Learning. pp.
419-439.
Additional Resou
Additional Resources listed at the End of this Lessonrces listed at the End of this Lesson
PRACTICE (50 MINS)
1. The learners are going to make fossils from a natural and man-made object.
2. There are two methods used to create fossils.
A. ImprintImprint
I. Choose the object you want to make a fossil of. Any natural object (shells, leaves, animal bone) will do as long as it fits in the container. If you choose leaves, be sure it is not dry.
II. Coat the object with petroleum jelly. This will keep the object from sticking to the plaster when you try to remove it. Coat it thoroughly.
III. Mix plaster and water in a bowl. Follow the directions on the plaster of Paris packaging. Mix them together thoroughly and let the concoction sit for a few minutes without stirring. You should need about 2x more water than plaster, but you can adjust the ratio as you see fit.
IV. Press the object into the plaster of Paris. Be careful not to push too hard! Now your part is done; all it has to do is dry. Set it aside and check it the next day; drying will take at least one day.
V. Remove the object. After you've waited 24 hours, pop your natural item out of the plaster of Paris. It's just like a shell that was enveloped in soil for thousands of years. It was disintegrated and this image was left behind.
B.
B. 3-D Object (Cast)3-D Object (Cast)
I. Choose the object you want to make a fossil of. Any natural object (shells, leaves, animal bone) will do as long as it fits in the container. If you choose leaves, be sure it is not dry.
II. Combine the plaster of Paris with water. Use 1 part plaster of Paris to 2 parts water and mix well in a paper cup with a plastic spoon. Let it sit while you work with the clay.
III. Choose an object as the template of your fossil. Generally, leaves, shells, branches, or bones work best. Just make sure you have enough clay and plaster to cover it.
IV. Knead the modeling clay until it is soft and pliable. This will be what your object rests and forms an impression in. It needs to be kneaded until it can cover the area of your object.
V. Coat the object with petroleum jelly. Firmly yet slowly press it into the modeling clay to
Teacher Tip:
Teacher Tip:
Making fossil is a fun way to get involved in science. There are a lot of online sites to guide you on how to create cheap replicas of fossils.
The activity can be a little messy, so instruct the learners to use newspapers or this can be done in an open area.
The following materials are needed for this activity.
1. A small natural object (shell, bone, leaf) 2. Any small toy
3. Clay 4. Petroleum jelly 5. Plaster of Paris 6. Disposable dish
Teacher Tip:
Teacher Tip:
Given that this can be messy, tell learners to work on top of old newspapers. Tell them not to throw plastic of Paris in the sink or drainage in order for them not to get clogged with the dried up materials. Provide a container for them to put all waste materials.
It will take 1 - 2 days to completely dry and harden the fossil model.
Give incentives/ small tokens to those who made the best fossils.
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make an impression. The petroleum jelly prevents it from sticking to the clay, so be generous. Remove the object carefully to create a mold in the shape of the item you used.
VI. Fill the impression left by your object with plaster of Paris. Smooth the plaster to the level of the clay to form a flat surface. Place your clay and plaster mold on a newspaper, paper towel, or other disposable surface and allow it to harden. You'll need to wait at least overnight, but 2 or 3 days is preferable and safer.
VII. Peel the clay off the hardened plaster to free the fossil. The shape of your object should be recreated in the plaster, details intact.
WRAP UP (10 MINS)
1. Tell the learners to clean up and put all the output in one corner of the room for them to dry up.
2. Tell them to label their works with masking tape.
General Biology 2
Lesson 8.5: History of Life on Earth Lesson 8.5: History of Life on Earth
Content Standard Content Standard
The learners demonstrate understanding of the major events in the history of life on Earth.
Performance Standards Performance Standards The learners shall be able to
• create a personal timeline and compare it with the geologic time scale; and
• design a poster tracing evolutionary changes in a crop plant (e.g., rice or corn) that occurred through domestication
Learning Competency Learning Competency
The learners describe general features of the history of life on Earth, including generally accepted dates and sequence of the geologic time scale and characteristics (STEM_BIO11/12-IIIc-g-8STEM_BIO11/12-IIIc-g-8)
Specific Learning Outcomes Specific Learning Outcomes
At the end of the lesson, the learners will be able to:
• identify the dates and sequence of the periods in the geologic time scale;
• identify the major events in each major period;
• describe the characteristics of the major groups of organisms present during a time period;
• identify types of fossils; and
• describe causes of mass extinctions.
60 MINS 60 MINS
LESSON OUTLINE - DAY FIVE
Evaluation
Evaluation Summative Assessment 60
Materials Materials
Visual aids on the geologic time scale; 20 printed pictures of events/
structures/ organisms; computers and internet connection Resources
Resources
(1) Freeman, S. Biological Science. 3rd ed. 2008. California: Pearson Benjamin Cummings. pp. 503-525.
(2) Reece, JB, LA Urry, ML Cain, S Wasserman, PV Minorsky, RB Jackson.
Campbell Biology. 9th ed. 2014. Illinois: Pearson Education Inc. pp.
480-499.
(3) Russell PJ, SL Wolfe, PE Hertz, C Starr, B Mc Millan. Biology: the Dynamic Science. 2008. California: Brooks/Cole CENGAGE Learning. pp.
419-439.
Additional Resou
Additional Resources listed at the End of this Lessonrces listed at the End of this Lesson
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SUMMATIVE ASSESSMENT SUMMATIVE ASSESSMENT
1. Geologic Time Scale Practice
Go to this site and try the quiz. (There is no need to memorize the smaller divisions of the geologic time scale.) http://
www.geosci.ipfw.edu/gildner/TimeScalePractice.html (Downloaded 04/16/16)
2. Geologic Time Scale Events
Go to this site and try the quiz. http://www.glencoe.com/qe/
scienceOLC.php?qi=6024 (Downloaded 04/16/16)
3. Practice Quiz for the Nature of Fossils
Go to this site and try the quiz. http://anthro.palomar.edu/time/
quizzes/timquiz1.htm (Downloaded 04/16/16)
MULTIPLE CHOICE
MULTIPLE CHOICE. Choose the letter of the correct answer.
1. The largest division of the geologic time scale is the A. Eon
B. Era C. Period D. Epoch
2. The Mesozoic Era was the Age of Reptiles while the current Cenozoic Era is the Age of
A. Mammals B. Birds C. Humans D. Technology
3. The layers in sedimentary rocks are also called A. eras
B. epochs C. strata D. gaps
4. The movie “Jurassic Park” got its title from which era?
A. Paleozoic B. Mesozoic C. Cenozoic D. Holozoic
5. During which era were the first land plants formed?
A. Cambrian B. Pre-Cambrian C. Paleozoic D. Mesozoic
6. The era of middle life, a time of many changes on Earth A. Paleozoic
B. Mesozoic C. Cenozoic D. Holozoic
7. What is the longest part of Earth’s history where trace fossils appeared.
A. Pre-Cambrian B. Paloezoic C. Mesozoic D. Cenozoic
8. The geologic time scale is subdivided into 4 groups. List them from the largest to the smallest.
A. Eons, periods, epochs, eras B. Eras, eons, periods, epochs C. Epochs, periods, eras, eons D. Eons, eras, periods, epochs
9. The end of this era was believed to be caused by a comet or asteroid colliding with Earth, causing a huge cloud of dust and smoke to rise into the atmosphere, blocking out the sun.
A. Paleozoic B. Holozoic C. Mesozoic D. Cenozoic
10. Which geologic event occurred during the Mesozoic era?
A. Pangaea formed
B. Asteroids killed the dinosaurs C. The Rocky Mountains formed D. The Pleistocene Ice Age began
TRUE OR FALSE.
TRUE OR FALSE.Write True if the statement is correct and False if it is not.
1. Fossils give clues about the past.
2. Animals that are extinct are still alive today.
3. Scientists do not know for sure what happened to the dinosaurs.
4. A mold is a cast filled in with sediments.
5. Soft body parts cannot be fossilized.
6. Paleontology is the study of fossils.
7. A wooly mammoth’s footprint is a trace fossil.
8. Distinctive fossils used to determine the ages of rocks are called scale fossils.
9. Saber - toothed tiger is more likely preserved in amber.
10. Fossils are most likely found in sedimentary rocks.
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RESOURCES:
RESOURCES:
NOTES:
NOTES:
1. The Geologic Time Scale: http://www.uky.edu/KGS/education/geologictimescale.pdf (Retrieved 07/08/15) 2. What Is a Fossil: http://www.discoveringfossils.co.uk/whatisafossil.htm (Retrieved 04/16/16)
3. BBC- Fossils: http://www.bbc.co.uk/nature/fossils (Retrieved 04/16/16)
4. How Fossils Form: http://www.enchantedlearning.com/subjects/dinosaurs/dinofossils/Fossilhow.html (Retrieved 04/16/16)
VIDEOS:
VIDEOS:
1. Evolution (1971 animation)- https://www.youtube.com/watch?v=T1_vnsdgxII (viewed 07/08/15) 2. Geologic Time Scale
3. The Geologic Time Scale: https://www.youtube.com/watch?v=r10oh1NHKv4&spfreload=10 (viewed 07/08/15) 4. The Geologic Time Scale: https://www.youtube.com/watch?v=nofyRleo3Vc (viewed 07/24/15)
5. Four Ways to Understand the Earth’s Age: https://www.youtube.com/watch?v=tkxWmh-tFGs&spfreload=10 (viewed 07/08/15) 6. The History of Earth: https://www.youtube.com/watch?v=RQm6N60bneo (viewed 07/08/15)
FURTHER
FURTHER: Advance learners can explore these sites beyond class.
1. Deep Time: A History of the Earth – Interactive Infographic: http://deeptime.info (viewed 07/09/15)
2. National Museum of Natural History – Geologic Time: http://www.nmnh.si.edu/paleo/geotime/index.htm(viewed 07/09/15) 3. Abiogenesis: https://www.youtube.com/watch?v=W3ceg--uQKM (viewed 07/08/15)
4. http://mitep.mtu.edu/include/documents/2013/presentations/What_is_the_Geologic_Time_Scale_DWagner.pdf 5. http://ed.ted.com/lessons/the-earth-s-age-in-measurements-you-can-understand-joshua-m-sneideman#review 6. http://www.stratigraphy.org/index.php/ics-chart-timescale
7. http://deeptime.info
8. http://www.nmnh.si.edu/paleo/geotime/index.htm
9. http://www.enchantedlearning.com/subjects/dinosaurs/dinofossils/Fossiltypes.html Other possible sources of quiz items on fossils: (Downloaded 04/16/16)
1. https://mrssmiths4thportfolio.wikispaces.com/file/view/fossil+quiz.pdf 2. http://www.marcom.com.au/SGuides/ZZVECS/6VCSQS06.pdf 3. https://www.nps.gov/blca/learn/education/upload/fossils-2.pdf 4. http://www.biorules.org/Biology/articles/hist_life/Chap12PracTest.pdf 5. http://scioly.org/wiki/images/4/44/2015CT_FOSS1_TESTKEY.pdf