Module 2: Living Systems in the Biological Perspective INTRODUCTION Whatever course you are taking, you encounter the word “system” in almost all of your subjects. In fact, everything that you come into contact with your day-to-day life is essentially either a system or a component of a system but you are perhaps not just conscious about it. Computer Science majors are maybe more familiar with an automated, computerized information system. Social Science students delve into political systems, and communication systems for those coming from Art Sciences. Though many “types of systems” appear to be quite different, there are common principles, philosophies and theories that apply remarkably well to virtually all kinds of systems, that is consisting of three kinds of things: elements or structures, interconnections or interactions that hold the elements together, and a function or purpose that produce their own pattern or behavior over time (Meadows, 2008). Apparently, biological principles play an important role in understanding the living systems that encompass all the microorganisms, plants, and animals including our own human race. The figure below shows the elements, interactions and function of a living system Figure 1. A diagram of a Living Systems (https://www.livingsystemsinst.org/embedded-nature) In addition, there is the “law of specialization”, one of the important systems principles explaining that the more highly adapted an organism is to a specific environment, the more difficult it is for the organism to adapt to a different environment. This probably explains why we often find our comfort zone and we get this nostalgic feeling of “There is no place like home”. Needless to say, it is important to understand the UPLB INSTITUTE OF BIOLOGICAL SCIENCES fundamentals of systems thinking to help us build and sustain stable, reliable systems that will function well in the complex society where we belong. This module further leads you into the realm of biology to appreciate the systems of living things. More importantly, you must also have a hint on what keeps a human society stable and what leads to its collapse. LEARNING OBJECTIVES At the end of this module, you are expected to: 1. 2. 3. 4. differentiate living from nonliving system distinguish the basic characteristics of living systems critique how living systems are organized and sustained value the importance of living systems ACTIVITY PLANNER Online Offline Live Activity Let’s begin ✔ Learning activity Dig Deeper On demand Points 120 ✔ ✔ ✔ Test Your Comprehension TOTAL ✔ Time (mins) 10 120 ✔ 30 120 360 Let’s begin with a READING ACTIVITY Read pages 1-34 of the book “Thinking in Systems: A Primer by Donella H. Meadows (2008) which can be retrieved from: https://research.fit.edu/media/site-specific/researchfitedu/coast-climate-adaptationlibrary/climate-communications/psychology-amp-behavior/Meadows-2008.-Thinking-inSystems.pdf UPLB INSTITUTE OF BIOLOGICAL SCIENCES Guide questions: 1. What is a system? 2. What differentiates living from nonliving systems? 3. How are living systems sustained? Dig Deeper: You might be interested to watch Donella H. Meadows’ lecture at Dartmouth College entitled “A Philosophical Look at System Dynamics.” Retrieved from: https://www.youtube.com/watch?v=XL_lOoomRTA LESSON 1 HIERARCHIES OF LIVING SYSTEMS Living systems are organized into hierarchies with progressive specialization of functions and complexity emerging from lower level to higher levels of organization also known as emergent properties. Oftentimes, the biological level of organization (See Reece et al., 2016; Starr et al., 2016) starts with atoms being the fundamental units of all substances, living or not. Atoms join other atoms to form molecules. In today’s natural world, only living things make the “molecules of life”, which are lipids, proteins, nucleic acids, and complex carbohydrates organized into organelles, which are membrane enclosed structures that perform specific functions to form the cells. The cell is the “basic unit of life”. Some cells live and reproduce independently while other specific types are organized as tissues. The organized array of tissues carrying out specific tasks is known as an organ. The set of interacting organs (organ system) make up the organism. An organism is an individual that consists of one (unicellular) or more cells (multicellular). Groups of interbreeding individuals of the same type or species living in a given area constitute the population. All populations occupying a given area form a community. The community and the non-living environment function together as an ecological system or ecosystem, the first unit that is complete because it has all the components necessary for survival (Odum and Barrett, 2005). The most inclusive level encompassing all regions of Earth’s crust, waters, and atmosphere in which organisms live is designated as the biosphere or ecosphere. The eleven ecological levels-of-organization of living systems (also called biosystems) from cell to ecosphere is shown in Figure 2. UPLB INSTITUTE OF BIOLOGICAL SCIENCES Figure 2. Eleven ecological levels-of-organization hierarchy with the seven transcending processes or functions as depicted by Barrett and colleagues in 1997 (cited in Odum and Barrett, 2005). While each level in the hierarchy exists in physical space and time, it is expected to have unique emergent and collective properties with increasing complexity brought about by internal dynamic interactions and exchanges with their environments. Yet there are seven basic functions (also known as transcending factors depicted as vertical components in Fig. 2) that operate at all levels including energetics, behavior, development, evolution, diversity, integration, and regulation. The salient characteristics that each level of organization shares has also been described by James Miller in his Living System Theory. These five major elements UPLB INSTITUTE OF BIOLOGICAL SCIENCES include: 1) structure or the arrangement of the components; 2) process or any change over time of matter and energy; 3) subsystem which is the totality of structures and their functions; 4) structural and process relationships and 5) systems process that requires the concerted action of many or all parts of the system (Duncan, 1972). The totality of the structures in a system that functions for a specific task is classified into 19 subsystems. These subsystems are further categorized into the following 1) that will produce matter/ energy; 2) that will process matter/energy (Figure 3); and 3) involved in information processing Figure 4). Table 1 . Subsystems involve processing only of matter and energy. (Duncan, 1972) Ingestor Brings matter-energy across the system boundary from its environment Distributor Carries inputs from outside the system or outputs from its subsystems around the system to each component. Converter Changes certain inputs to the system into forms more useful for the special processes of that particular system Producer Forms stable associations that endure for significant periods among matter energy inputs to the system or outputs from its converter, the materials synthesized being for growth, damage repair, or replacement of components of the system, or for providing energy for moving or constituting the system’s outputs of products or information markets to its suprasystem Matter-energy storage Retains in the system, for different periods of time, deposits of various sorts subsystem of matter-energy Extruder Transmits matter-energy out of the system in the form of products or wastes. Motor Moves the system or parts of it in relation to part or all of its environment or moves components of its environment in relation to each other Supporter Maintains the proper spatial relationships among components of the system, so that they can interact without weighing each other down or crowding each other UPLB INSTITUTE OF BIOLOGICAL SCIENCES Table 2. Group consisting of information processing subsystems. (James G Miller’s Living System Theory in Duncan, 1972) Input transducer Brings markers bearing information into the system, changing them to other matter-energy forms suitable for transmission within it Internal transducer Receives, from other subsystems or components within the system, markers bearing information about significant alterations in those subsystems or components, changing them to other matter-energy forms of a sort that can be transmitted within it Channel and net Composed of a single route in physical space, or multiple interconnected routes, by which markers bearing information are transmitted to all parts of the system Decoder Alters the code of information input to it through the input transducer or internal transducer into a private code that can be used internally by the system Associator Carries out the first stage of the learning process, forming enduring associations among items of information in the system Memory Carries out the second stage of the learning process, storing various sorts of information in the system for different periods of time Decider Receives information inputs from all other subsystems and transmits to them information outputs that control the entire system Encoder Alters the code of information input to it from other information processing subsystems, from a private code used internally by the system into a public code that can be interpreted by other systems in its environment Output transducer Puts out markers bearing information from the system, changing markers within the system into other matter-energy forms that can be transmitted over channels in the system’s environment. UPLB INSTITUTE OF BIOLOGICAL SCIENCES Living system continues indefinitely within the natural cycles to attain sustainability (Figure 3). Figure 3. Model system depicting the sustainability theory (http://www.naturalstep.org/en/the-science-behind-our-approach) The sun-driven process of photosynthesis acted upon by the plants generates the net increases in material quality on Earth almost entirely. This makes a living system an “open” system because during photosynthesis, plants convert energy from sunlight (input) to chemical energy (stored in food molecules such as sugars), which is used by plants to do work. This energy is then transferred to the higher trophic levels (consumers) and is eventually lost from the ecosystem as heat (output). The cycling of matter from plant to animals through consumption and the breakdown of these matter back to its elemental form through decomposition mostly driven by mircoorganisms to become utilized again by the plants somehow make the living system a relatively closed system. Unutilized decomposed materials become slowly deposited through sedimentation and mineralization and become available again through slow geological cycles such as volcanic eruptions and weathering. This natural cycle is also known as biogeochemical cycles. UPLB INSTITUTE OF BIOLOGICAL SCIENCES The natural system with its self-organizing capacity will persist without humans, but humans cannot live without it. After all, we only have one Earth to live in, why don’t we save it? LEARNING ACTIVITY 1. Go and get a Tilapia fish: either one from the kitchen, buy from the market or view the picture of one (Figure 4). 2. Examine the form, the shape and the rest of the external structures. If you can hold one, the better it is so you can actually do the “dissecting”. Using a knife or kitchen scissors, open up the belly, that is, the ventral side (bottom side) of the fish (Figure 5). 3. List down the parts and organs (e.g. skin and stomach) you can see and identify tissues (e.g. muscles and bones). 4. From this information, make a diagram of the level of organization. You will start with the fish as an organism (so this will be near the middle of your diagram). What are the structures that you were able to see? What makes up these structures? How would this tilapia be a part of the ecosphere? (Clue: watch the video https://youtu.be/lj_VyaV91Og) 5. Discuss the hierarchy of this living system. Prepare a written and a video report. Figure 4. Sample specimen of a Tilapia https://commons.wikimedia.org/wiki/File:Tilapia_oreochromis_niloticus_fish.jpg UPLB INSTITUTE OF BIOLOGICAL SCIENCES Figure 5. Demonstration of dissecting fish by cutting through the belly or ventral side. https://upload.wikimedia.org/wikipedia/commons/9/9c/Devin_Chappell_Dissecting_Fish_%285544521748 %29.jpg SCORING RUBRIC FOR LEARNING ACTIVITY (10pts) Categories Comprehension Discussion reflects a good perception of key ideas from the module and resources. Discussion connects the topic to related ideas and concepts Presentation of Diagrams Diagrams are clearly and concisely represented: Diagrams are neat and properly labeled Communication Skills Presentation and discussion are presented in correct academic language Sub total UPLB INSTITUTE OF BIOLOGICAL SCIENCES Yes Partly No (2 pts) (1 pt) (0 pt) Remarks LESSON 2 PROPERTIES OF LIVING SYSTEMS When a living creature dies, it loses its “system-ness” according to Meadow (2008). She added that, “the multiple interrelations that held it together no longer function, and it dissipates, although its material remains part of a larger food-web system”. Any other system for that matter will collapse or lose its system-ness when all the parts are gone or are no longer functioning. To differentiate whether a system is living or not, there are certain attributes or properties that can be observed. This section specifically tackles the characteristics of living systems from a biological perspective. But wait...let us do a simple activity… Look outside your window and stare at the scene in front of you. Notice the colors, the sizes, the shapes and the movement, if any, of the many objects. List down ten (10) objects that you see. Encircle the name of each of the living things and put a “check” mark for the non living things. Now answer the following questions: 1. How were you able to distinguish the living from the non-living thing? 2. What are the common features of the living things in your list? of the non-living things? As for me, I have this view from my window: a collection of plants, an occasional butterfly, a roaming cat and the neighbor’s house. Essentially what I see are systems, one of which is a system of living things. What then is a living system in a biological perspective? It has to have properties. These properties or characteristics include the following: order; energy processing; regulation and homeostasis; sensitivity to stimuli; growth and development; reproduction (heredity and variation) and adaptation . Order Now focus on the plant and examine its form. The form of a living thing shows a highly organized and coordinated set of structures or units that is in harmony to produce a specific function. There is order in living things i.e., from a single celled organism to multicellular advanced organisms. The plant that you observed or the cat that you saw are examples of living things that is part of the hierarchy of living systems. UPLB INSTITUTE OF BIOLOGICAL SCIENCES Energy processing All organisms use a source of energy for their metabolic activities. Some organisms like the plant outside my window, capture energy from the sun and convert it into chemical energy in food. On the other hand, other organisms like the cat walking in our yard take in food as a source of chemical energy. Response to Stimuli Organisms respond to diverse stimuli. For example, plants can bend toward a source of light, climb on fences and walls, or respond to touch (Figure 6). Even tiny bacteria can move toward or away from chemicals (a process called chemotaxis) or light (phototaxis). Movement toward a stimulus is a positive response, while movement away from a stimulus is a negative response. Figure 6. The leaves of this sensitive plant (Mimosa pudica) will instantly droop and fold when touched. After a few minutes, the plant returns to normal. https://commons.wikimedia.org/wiki/File:Mimosa_pudica_a.jpg Regulation/Homeostasis Even the smallest organisms are complex and require multiple regulatory mechanisms to coordinate internal functions, respond to stimuli, and cope with environmental stresses. Two examples of internal functions regulated in an organism are nutrient transport and blood flow. Organs (groups of tissues working together) perform specific functions, such as carrying oxygen throughout the body, removing wastes, delivering nutrients to every cell, and cooling the body. UPLB INSTITUTE OF BIOLOGICAL SCIENCES In order to function properly, cells require appropriate conditions such as proper temperature, pH, and appropriate concentration of diverse chemicals. These conditions may, however, change from one moment to the next. Organisms are able to maintain internal conditions within a narrow range almost constantly, despite environmental changes, through homeostasis (literally, “steady state”). For example, an organism needs to regulate body temperature through the thermoregulation process. Organisms that live in cold climates, such as the polar bear (Figure 7), have body structures that help them withstand low temperatures and conserve body heat. Structures that aid in this type of insulation include fur, feathers, blubber, and fat. In hot climates, organisms have methods (such as perspiration in humans or panting in dogs) that help them to shed excess body heat. Figure 7. Polar bears (Ursus maritimus) and other mammals living in ice-covered regions maintain their body temperature by generating heat and reducing heat loss through thick fur and a dense layer of fat under their skin. (https://commons.wikimedia.org/wiki/File:Polar_Bear_AdF.jpg) Growth and Development Organisms grow and develop as a result of genes providing specific instructions that will direct cellular growth and development. This ensures that a species’ young (FIgure 8) will grow up to exhibit many of the same characteristics as its parents. Figure 8. Although no two look alike, these kittens have inherited genes from both parents and share many of the same characteristics. (credit: Rocky Mountain Feline Rescue) UPLB INSTITUTE OF BIOLOGICAL SCIENCES Reproduction Reproduction is essential to organisms as it ensures the continuity of the species. The From unicellular to multicellular organisms, duplicating their DNA, and then dividing it equally as the cell prepares to divide to form two new cells. Multicellular organisms often produce specialized reproductive germline, gamete, oocyte, and sperm cells. After fertilization (the fusion of an oocyte and a sperm cell), a new individual develops. When reproduction occurs, DNA containing genes are passed along to an organism’s offspring. These genes ensure that the offspring will belong to the same species and will have similar characteristics, such as size and shape. Adaptation All living organisms exhibit a “fit” to their environment. Biologists refer to this fit as adaptation, and it is a consequence of evolution by natural selection, which operates in every lineage of reproducing organisms. Examples of adaptations are diverse and unique, from heat-resistant Archaea that live in boiling hotsprings to the tongue length of a nectarfeeding bird that has beaks adapted to the flower from which it feeds (Figure 9). All adaptations enhance the reproductive potential of the individuals exhibiting them, including their ability to survive to reproduce. Adaptations are not constant. As an environment changes, natural selection causes the characteristics of the individuals in a population to track those changes. Figure 9. The nectivore bird with its long pointed beak as it feeds on the nectar of flowers. https://commons.wikimedia.org/wiki/File:Bananaquit_(4451414324).jpg UPLB INSTITUTE OF BIOLOGICAL SCIENCES LEARNING ACTIVITY In the first few meetings, you were asked to watch the series of lectures of Donella Meadows on Youtube. Having in mind the key concepts on Systems Thinking by Meadows, you will be watching the video, “In a World of Systems” illustrated and narrated by David Macaulay. (Retrieved from https://www.youtube.com/watch?v=A_BtS008J0k) Activity: Testing your comprehension Length of video: 9:22 Estimated Time to Finish Task: 30 minutes Discussion: 40 minutes After watching the video, come up with answers to the following: 1. What types of systems were mentioned in the video? 2. Which of these systems are living? non-living? 3. Develop a model that will depict any type of system that was mentioned in the video. Make sure that you are able to show the elements or structures and the interconnections. Guided by your models, you should be able to explain how the system is organized to achieve its purpose. Other videos: ● Systems-thinking: A Little Film About a Big Idea (11:55 mins) Retrieved from: https://www.youtube.com/watch?v=-sfiReUu3o0 ● A Systems Story (Systems Thinking) (4:45mins) Retrieved from: https://www.youtube.com/watch?v=rDxOyJxgJeA UPLB INSTITUTE OF BIOLOGICAL SCIENCES SCORING RUBRIC FOR THE Activity: Testing your comprehension (10PTS) Categories Yes Partly No (2 pts) (1 pt) (0 pt) Remarks Comprehension Discussion reflects a good perception of key ideas from the module and resources Discussion connects the topic to related ideas and concepts Presentation of Models Models are clearly and concisely represented Models are neat and properly labeled Communication Skills Presentation and discussion is presented in correct, academic language Sub-total SELF-ASSESSMENT After studying the module resources and accomplishing the learning task for this module, check whether you are able to do the following: o o o o differentiate living from nonliving system distinguish the basic characteristics of living systems understand how living systems are organized and sustained appreciate the importance of living systems REFERENCES Duncan, D.M. (1972). James G. Miller’s Living Systems Theory: Issues for Management Thought and Practice. The Academy of Management Journal. 15(4):513-523. Meadows, D. H. (2008). Thinking in Systems: A Primer. UK: Sustainability Institute. Retrieved from https://research.fit.edu/media/site-specific/researchfitedu/coast-climateadaptation-library/climate-communications/psychology-amp-behavior/Meadows-2008.Thinking-in-Systems.pdf UPLB INSTITUTE OF BIOLOGICAL SCIENCES Odum, E.P and G.W. Barrett. 2005. Fundamentals of Ecology. 5th ed. Singapore: Brooks/Cole, Thomson Learning Asia. 598p. Reece, J. B., Taylor, M. R., Simon, E. J., Dickey, J. L., Hogan, K., & Campbell, N. A. (2015). Campbell Biology: Concepts & Connections (8th ed.). Harlow, England: Pearson Education. Starr, C., Evers, C. A., & Starr, L. (2016). Biology: Today and Tomorrow (5th ed.). United States of America: Cengage Learning.Starr, C., Taggart, R., Evers, C., & Starr, L. (2016). Biology: The Unity and Diversity of Life (14th ed.). Canada, United States of America: Cengage Learning. Brooker, R. J., Widmaier, E. P., Graham, L. E., & Stiling, P. D. (2014). Biology (3rd ed.). New York: McGraw-Hill Education. Reece, J. B., Taylor, M. R., Simon, E. J., Dickey, J. L., Hogan , K., & Campbell, N. A. (2015). Campbell Biology: Concepts & Connections (8th ed.). Harlow, England: Pearson Education. Mader, S. S., & Windelspecht, M. (2016). Biology (12th ed.). New York: McGraw-Hill Education. Starr, C., Evers, C. A., & Starr, L. (2016). Biology: Today and Tomorrow (5th ed.). United States of America: Cengage Learning. Russell, P. J., Hertz, P. E., & McMillan, B. (2015). Biology: The Dynamic Science (4th ed.). Canada, United States of America: Cengage Learning. Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V., & Reece, J. B. (2016). Campbell: Biology in Focus (2nd ed.). United States of America: Pearson Education. UPLB INSTITUTE OF BIOLOGICAL SCIENCES