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2 MODULE Living Systems in the Biological Perspective

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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
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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
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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.
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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
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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
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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.
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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.
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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
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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
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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.
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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.
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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)
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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
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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
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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
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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.
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