Study Guide I
.pdf
School
University of California, Berkeley**We aren't endorsed by this school
Course
ESPM 6
Subject
Biology
Date
Dec 17, 2024
Pages
3
Uploaded by HighnessElkMaster681
1. How can we use this insight to help us with the difficult problem of defining Life? Whatwords in these quoted texts can help in moving away from thinking of Life as a Noun, i.e.a Thing? Which of these (Han, Proust) might be a primary reference and why?●Insight from Han and Proust can help us redefine the concept of Life by emphasizing itsdynamic and process-oriented nature rather than treating it as a static noun. Both Hanand Proust's texts emphasize the temporal dimension and the continuous flow ofexperiences and existence. Words and concepts that can help shift away from thinkingof Life as a mere noun include "process," "experience," "continuity," and "evolution."●Han's work might serve as a primary reference because he discusses the notion of lifeas a flow and a continuous process, which aligns with the fundamental principles ofbiology. Proust's work, while valuable, may be considered more within the realm ofliterature and philosophy rather than a direct reference for biological concepts.2. Are we (humans) the phylogenetic descendants of “dead” people? In what sense isthere continuity between you and your living ancestors, and how far back in thephylogenetic dimension can you follow this continuity? Is a bacterium alive today yourliving ancestor? A chimpanzee?●Yes, humans are indeed the phylogenetic descendants of our ancestors, including thosewho are no longer alive. The continuity between living individuals and their ancestorscan be traced back through the tree of life, which encompasses all living organisms.While a bacterium today is not a direct living ancestor of humans, it represents anevolutionary branch on the tree of life from which both bacteria and humans sharecommon ancestors. Similarly, chimpanzees share a more recent common ancestor withhumans, making them closer relatives in terms of phylogenetic relationships.3. Some people think that "forever twenty-one" can be made into a biological reality.Read, for example, today's news article on the subject here (and below).Is this desirable? What would you say to proposals to extend human life to say 150 yearsold?How about 500? Where would you draw a limit to this?●The idea of extending human life significantly beyond the typical lifespan raises ethicaland practical considerations. While increasing human lifespan to 150 years or even 500years may sound appealing on the surface, it poses various challenges:●a. Resource Constraints: A significantly longer human lifespan would strain Earth'sresources, including food, water, and energy, potentially exacerbating issues related tooverpopulation and resource depletion.●b. Social and Economic Implications: Extending human life could impact retirement,workforce dynamics, and social systems. It might require rethinking societal structures,such as retirement age and healthcare.●c. Ethical Considerations: Questions about the quality of life, access to healthcare, andpotential disparities in lifespan extension would need to be addressed.●d. Environmental Impact: Extended lifespans could lead to increased consumption andenvironmental degradation, affecting biodiversity and ecosystems.
I believe that human death is a necessary part of human living because of various reasons. Ifpeople were to live forever, there would not be enough resources to sustain all the people onEarth since there would be an overpopulation. People would have to compete for food, water,living spaces and energy. Additionally, this could have a detrimental impact on the environment,since there would be more consumption overall (such as using trees for paper). On top of that,there might not be accessible healthcare for everyone if people are living for a super long time,since there would be more people that need it. Because of this, I believe that death isnecessary.4. Can I say that I can completely describe you as a life-form if I make a list of(a) all the molecules in your body, and(b) A three-dimensional map of where they are placed at this moment? Why or whynot?●No, you cannot completely describe a life-form simply by listing all the molecules in itsbody and creating a three-dimensional map of their placement. While knowing themolecular composition and spatial arrangement of molecules is important, life-forms aremuch more than just their physical components. Life is characterized by complexprocesses such as metabolism, reproduction, growth, and response to stimuli. It involvesintricate interactions between molecules, cells, tissues, and organs, as well as the abilityto adapt and evolve. Therefore, a comprehensive description of a life-form also requiresan understanding of its biological functions, behavior, and evolutionary history.5. Consider the sketch drawn by Charles Darwin in his Notebook D, found here. Thisdrawing implies phylogenetic relationships between life-forms A, B, C and D. What doesthis mean? Was Darwin thinking, in this diagram about time or only relationships? Whatis a phylogram? How is this different from a genealogical tree?●The sketch by Charles Darwin in his Notebook D implies phylogenetic relationshipsbetween life-forms A, B, C, and D. This means that Darwin was thinking about theevolutionary relationships among these organisms, indicating their common ancestryand the branching points in their evolutionary history. The diagram primarily representsrelationships rather than specific timeframes.A phylogram is a type of phylogenetic tree that includes information about the amount ofevolutionary change between species. It uses branch lengths to represent the amount of geneticor evolutionary divergence. This is different from a genealogical tree, which typically focuses onthe relationships between individuals or families without necessarily considering the amount ofevolutionary change.6. What was the Great Oxidation Event? What evidence do we have to say that ithappened? Who/what was responsible for it? Would you think it would be a good ideatoday to reverse this event, and do you think this is something we have the power to do?
●The Great Oxidation Event was a significant event in Earth's history that occurredapproximately 2.4 billion years ago. It marked a dramatic increase in the atmosphericoxygen levels, primarily due to the photosynthetic activity of early cyanobacteria(blue-green algae). This event led to the oxygenation of Earth's atmosphere and hadprofound effects on the planet's geochemistry and the evolution of life.●Evidence for the Great Oxidation Event comes from geological records, such as thepresence of iron-rich sediments known as banded iron formations and the chemicalcomposition of ancient rocks. Isotopic signatures in these rocks indicate a shift in theabundance of oxygen in the atmosphere.●Reversing the Great Oxidation Event today would be neither feasible nor desirable. Thehigh levels of oxygen in Earth's atmosphere are essential for the respiration of aerobicorganisms, including humans. Attempting to reverse this event would have catastrophicconsequences for most life forms on the planet.7. Where does the water on our planet come from originally, and why is it still here in away that allows life to thrive?●a. Primordial Water: Some of Earth's water was present during the planet's formation aspart of the solar nebula that condensed to form the Earth.b. Cometary Water: Water was delivered to Earth by comets and asteroids during theLate Heavy Bombardment period.c. Volcanic Outgassing: Water vapor released from volcanic activity contributed to theEarth's early atmosphere and surface water.d. Chemical Reactions: Chemical reactions between elements in the Earth's crust andmantle, such as the hydration of minerals, also released water.The water on Earth is still here because of the planet's unique conditions. Earth's gravity andrelatively stable climate have helped retain water in liquid form, making it available for life tothrive. The water cycle, driven by evaporation, condensation, precipitation, and runoff,continuously redistributes and replenishes the planet's water reservoirs, ensuring a sustainablesupply of water for life.Freebie: Prepare to give a very brief answer in the Quiz to the question below:What came first, the chicken or the egg?The egg came first because genetic mutations gradually led to the first chicken hatching from anegg laid by a bird that was not quite a chicken.