Layman D. Biology Demystified: A Self-Teaching Guide

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5. Living organisms undergo metabolism for energy production and excrete

unuseable waste products. The word metabolism (meh-TAB-ah-lizm) means ‘‘a

state of change.’’ In living things, food that is eaten is soon changed by the

chemical processes of metabolism. Energy is produced, which then performs

body work. Excretion (eks-KREE-shun) is a ‘‘sifting out’’ of waste matter

after metabolism, thereby eliminating it from the body.

6. Living organisms reproduce themselves. A living creature has the ability

to reproduce itself, either sexually (using sex) or asexually (ay-SEK-shoe-ah-

lee) – ‘‘not’’ (a-) using sex.

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Fig. 1.2 Some patterns representing biological order.

(A)

(B)

What Did The Cavemen Know About Biology?

Apparently, the very earliest people knew a lot about biology! Ancient caves

have been discovered in various parts of the world. The walls of many of

these caves are richly decorated with pictures of plants, birds, animals, and

the humans hunting them.

Over 2000 years ago, the Early Egyptians brushed colorful paintings of

living things onto the walls of their temples and coﬃns. It must have been

very important for these people to begin The Search for Biological Order, a

search for predictability and meaning in their natural environment. By dis-

covering the underlying patterns of plant and animal structure, function, and

behavior, early humans could ensure a more consistent supply of food.

Biological Disorder: A Reality Since Ancient

Times

Earlier, we said that a state of Biological Order (particular patterns asso-

ciated with living things) was an important property of organisms. It is only

logical, therefore, for us to assume that ancient people were likewise aware of

its exact opposite – Biological Disorder:

Recall that Figure 1.2 showed some patterns representing Biological

Order: There was a giraﬀe with its intricate pattern of black spots, and an

S-shaped curve represented a normal range where something (like oral body

temperature) remained relatively constant over time. In a dramatically oppo-

site way, Figure 1.3 (A) represents Biological Disorder symbolically as a dead

giraﬀe without its spots! And Figure 1.3 (B) reveals that a disordered state of

something like oral body temperature would be represented by a curve that

rose either signiﬁcantly above its normal range, or signiﬁcantly below it.

In general, a condition of Biological Order is associated with health and

lack of injury. Conversely, a condition of Biological Disorder is often asso-

ciated with disease, injury, or death of the organism.

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1, Disorder

2, Disorder

4, Order

A healthy long bone, for example, has a high degree of Biological Order.

But a fractured long bone, in marked contrast, reﬂects a lot of Biological

Disorder. From the very earliest days of human existence, bone fractures

have been very common. Hence, surely mankind has always been aware of

Biological Disorder (broken patterns) of various kinds, even though ancient

people may not always have been consciously thinking about it.

(NOTE: As you have already seen, key facts describing some aspect of

Biological Order for an individual organism will usually be tagged by the

spotted giraﬀe icon. And key facts describing a feature of Biological Disorder

will be tagged by a dead giraﬀe that has lost its spots.)

Order beyond the Individual Organism: The

Spider and its Web

Beyond the internal environment within a particular organism, lies the exter-

nal (eks-TER-nal) environment – the surrounding area ‘‘outside of ’’ the

body. The external environment basically involves patterns in ecology

(e-KAHL-oh-jee), including various ecological (e-koh-LAHJ-ih-kal) relation-

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Fig. 1.3 Some broken patterns representing biological disorder.

(B)(A)

ships. Ecology exactly translates to mean ‘‘study of household aﬀairs’’ in

common English. Ecology is the study of the relationships between diﬀerent

organisms, and the ‘‘aﬀairs’’ between these organisms and the total ‘‘house-

hold’’ of the external environment. Ecology would not focus upon just an

individual giraﬀe, for example. Rather, it would expand its focus beyond the

single giraﬀe organism, to other nearby giraﬀes, other species, and even the

entire external environment of the African plain.

We might picture ecology (ecological relationships) as a vast, intercon-

nected spider web. Therefore, Biological Order in the external environment

beyond the organism reﬂects a healthy or successful pattern of ecological

relationships. We will represent this Order symbolically by a spider in its

web (Figure 1.4, A). Conversely, Biological Disorder beyond the organism

reﬂects a breaking of the normal pattern of ecological relationships. This

state of environmental Disorder is indicated by the icon of a dead spider

and its broken web (Figure 1.4, B).

Natural History: The Search for Order Begins in

Earnest

Although ancient peoples around the world have been informally learning

about Biological Order (and its counterpart, Biological Disorder) for thou-

sands of years, a systematic approach to the search for Order has only begun

relatively recently. Aristotle (AIR-ist-ahtl), who lived during 384–322

B.C.in

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1, Web

1, B-Web

Fig. 1.4 Symbols for order and disorder in the external environment.

(B)(A)

Greece, was one of the ﬁrst natural philosophers (Figure 1.5). Aristotle may

have been the world’s ﬁrst great biologist. He collected huge amounts of

information about the anatomy, physiology, and behavior of many plants

and animals. He was the ﬁrst person to describe the diﬀerences between

plants and animals, and between living versus non-living things. Aristotle

studied the parts of living organisms in terms of their teleology (tel-e-AHL-

oh-jee), their ‘‘complete’’ (teleo-) or ﬁnal purpose for existence. The ﬁnal

‘‘purpose’’ of numerous plants and animals, this early biologist thought,

was to provide food for mankind, thereby adding to human happiness.

Aristotle emphasized the importance of making detailed observations to

help state general principles, and he assumed that the World of Nature

had a great deal of Order within it. Aristotle may also be considered the

Father of Natural History – the collection and classiﬁcation of plants and

animals into particular groups.

Aristotle’s ideas about a broad Natural History – the comprehensive study

of plants, animals, ﬁsh, birds, and all other living creatures – were widely

adopted and followed for hundreds of years. During the 1700s in Europe, a

number of brave explorers made dangerous journeys to faraway places

around the globe, collecting and classifying a great variety of plants and

animals. Gradually, the immense Biological Order of the world was becom-

ing quite apparent. The ability of naturalists to keep classifying newly dis-

covered organisms into particular groups was strong evidence of a high

degree of Order underlying the natural environment.

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Fig. 1.5 Aristotle: The world’s ﬁrst great biologist.

2, Web

The 1800s: Experimental Physiology Comes of

Age

By the 1800s, the collecting and classifying activities of Natural History were

becoming more and more replaced by the experimental method. In this

method, an hypothesis (high-PAHTH-eh-sis) or starting hunch is ‘‘placed’’

(thesis) ‘‘below’’ (hypo-) a group of facts as a tentative explanation. The

researcher then conducts an experiment to test the hypothesis or hunch

and collects some results. The results are compared to what was originally

predicted by the hypothesis. A conclusion is reached. Either the hypothesis is

accepted (being supported by the collected evidence) or it is rejected as not

being consistent with the evidence. By this more sophisticated experimental

method, no particular hypothesis is ever proven as ‘‘absolutely true.’’ There is

always the possibility that a new experiment may be conducted which will

provide contradictory evidence. Nevertheless, the experimental method

began to provide ever-closer and closer ﬁtting to the ‘‘real truth’’ as it exists

in our natural environment.

One of the key investigators using the experimental method in the mid-

1800s was a Frenchman named Claude Bernard (ber-NAR). Claude Bernard

was one of the ﬁrst experimental physiologists (ﬁz-e-AH-loh-jists). As ‘‘one

who studies’’ (-ologist) about body ‘‘Nature or function’’ (physi), Bernard

performed lots of experiments on dogs. Bernard did much of the early work

on homeostasis (hoh-mee-oh-STAY-sis). Homeostasis literally means a

‘‘control of sameness,’’ that is, a relative constancy, of the body’s internal

environment.

You may recall the S-shaped pattern from Figure 1.2 (A):

Remember that this pattern indicates the maintenance of a relative con-

stancy of oral body temperature within its normal range. This S-shaped

pattern therefore also generally indicates the existence of homeostasis of

any measured aspect of body structure or function. Claude Bernard, for

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5, Order

instance, measured blood glucose (GLOO-kohs) concentration in dogs.

Glucose is the most important sugar or ‘‘sweet’’ (gluc) substance within the

bloodstream. It is the major fuel for our body cells.

Using the experimental method, Bernard found that blood glucose con-

centration (like oral body temperature) remains relatively constant within its

normal range. Thus it, too, shows the characteristics of homeostasis.

Modern biology (especially physiology) owes much to Claude Bernard for

demonstrating the importance of the experimental method in detecting

homeostasis and other ‘‘truths’’ about living organisms.

Quiz

Refer to the text in this chapter if necessary. A good score is at least 8 correct

answers out of these 10 questions. The answers are listed in the back of this

book.

1. An organism is best described as:

(a) A collection of body structures

(b) A group of related body functions

(d) A living thing with a high degree of order

2. The structure of an organism is:

(a) The entire program of function it carries out

(b) The arrangement or pattern built up from its component parts

(d) The body parts which do not seem to ﬁt together very well

3. Anatomy is:

(a) Body structure and the study of body structures

(b) Body function and the study of body functions

(d) Seldom considered whenever body structures are being studied

4. Anatomy diﬀers from physiology in that:

(a) Only physiology occurs in living things

(b) Anatomy occurs in both living and dead organisms (not rotted

away)

(d) Anatomy only occurs in dead things

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5. Biological Order:

(a) Explains the occurrence of disease and injury

(b) Represents a particular pattern associated with living things

blood sugar

(d) Often prevents the body from responding to changes in the

environment

6. An S-shaped curve followed over time generally indicates:

(a) Lack of homeostasis

(b) Biological Disorder in the external environment

(d) The maintenance of some body structure or function within its

normal range

7. Biological Disorder is usually tied to:

(a) The creation of a particular pattern associated with living things

(b) A healthy and disease-free state

(d) Normal body structure and function

8. Ecology is best deﬁned as:

(a) The removal of diseased and damaged plants and animals from the

environment

(b) Study of the relationships between diﬀerent organisms and their

environment

(d) A complete lack of association between diﬀerent organisms and

their environment

9. Natural History essentially approaches Biological Order by:

(a) Naming and classifying newly discovered organisms

(b) Testing a formal hypothesis

(d) Conducting experiments on living organisms and reaching

conclusions from the results

10. Homeostasis:

(a) Does not usually exist in healthy individuals

(b) Represents a ‘‘control of sameness’’ or relative constancy of the

body’s internal environment

(d) Was extensively studied and deﬁned by Aristotle

The Giraﬀe ORDER TABLE for Chapter 1

(Key Text Facts About Biological Order Within An Organism)

1. ____________________________________________________________

2. ____________________________________________________________

3. ____________________________________________________________

4. ____________________________________________________________

5. ____________________________________________________________

The Dead Giraﬀe DISORDER TABLE for Chapter 1

(Key Text Facts About Biological Disorder Within An Organism)

1. ____________________________________________________________

2. ____________________________________________________________

The Spider Web ORDER TABLE for Chapter 1

(Key Text Facts About Biological Order Beyond the Individual Organism)

1. ____________________________________________________________

2. ____________________________________________________________

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The Broken Spider Web DISORDER TABLE for Chapter 1

(Key Text Facts About Biological Disorder Beyond the Individual

Organism)

1. ____________________________________________________________

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