Suggestions to do well in this class • Attend every lab session. • Give your undivided attention. • Ask the TA to repeat himself. • Review the power-point presentations before • the quiz. • Hand your assignment in due time. • Do your best with the lab. reports
How to • Access your web-page…run youhanna sawires on Yahoo • search engine then book-mark the URL • View your PowerPoint presentations…first you have • to have PowerPoint program installed on your computer. • If you do not, you may install it from MS-office suite. • If you do not have office,you may download and install • Open Office suite. If you done with that, just double click • the link • Prepare to the up-coming lab…. read the lab manual • (or review the PowerPoint presentation on my • web-page). • Make up a missed lab…it is preferred not to miss any • lab. session. However, if it happens, attend my second • session or contact Kaye Jay in the same day.
Announcement You have to get your student ID number by next week. There is a link through the student link. There is a quiz next week The home assignment is accessible through my web page and it is due in class next week. Next week lab. is “Macromolecules” Preceptor program..3 units class. Needs commitment Chance to develop teaching skills
Today lab. • Scientific thinking • Biology and scientific thinking • How to use scientific thinking to solve these • problems (games)
Science is basically common sense • It is not separate from everyday experience • - Isaac Newtin and the apple • - the light bulb issues • Biology is the science of living things Sir Isaac Newton
Scientific thinking • Observe • Question • Hypothesize • Predict • Experiment • Refine • Replicate
Let us get acquainted with some lab. techniques • -detecting the process of photosynthesis by the elaborated oxygen • . All land or water plants perform the process of photosynthesis. • . It is by which the plant get synthesize its nutrients. • . The plant utilize water and atmospheric co2 to synthesize • carbohydrates. In addition it releases oxygen as by product. • . Released oxygen get trapped in the plant tissue and cause it to • float when it is put in water. • . We will verify the occurrence of the process in spinach leaves and • develop some skills in doing the protocol.
.You need 5 discs per beaker. A few may not be good to use…… so cut 8 per beaker. .Cut out discs using the punch provided (Do not keep the spinach leaves outside…they wilt and then cannot be cut) .Put the discs immediately into a Petri dish with bicarb. .When all the discs have been cut…..then transfer them all into a syringe with bicarb in it. Do not damage the discs. Use a spatula provided to transfer the discs. .Now insert the plunger and point the syringe skyward and push out all the air. .Put your finger over the syringe tip and pull back on the plunger to create a vacuum within the syringe. Pull back a little at a time (approx. 1 ml ) so as not to damage the discs. .While still under vacuum remove your finger from the syringe tip. As the vacuum is released, the leaf discs fill with the bicarb buffer. .Repeat until all the discs sink in the buffer. .Pour the discs into a Petri dish
.Now transfer a fixed amount of discs in each beaker (5 or 6). You may need to tap the discs for them to sink (surface tension of the water) .Turn on the light on the table .Immediately now put all the beakers under the light. .Note the time
Exercise 1 • work in groups of 4 • Apply scientific thinking method to this evolving • string of numbers and predict what the next line • would be. • 1 5 • 1 1 1 5 • 3 1 1 5 • 1 3 2 1 1 5
Exercise 2 • work in groups of 4 • try to answer the question , how can you recognize • living from non living ? • -follow the steps of scientific thinking and come up • with a set of features (criteria) that help to to judge • the creatures that I will show you on the projector.
Exercise 3 • Where the mass of the tree come from • Work in groups of 4 • Hypothesize a theory or explanation and try • to prove or disprove it. • -we will supply soil, seeds, planting pots, etc.. • -The plant should be followed up to two to • three weeks