Download Restor (B2B78) - Exercise 1

Exercise No. 1
CONSTRUCTION OF A DICHOTOMOUS KEY
Name: Jonathan Jr. R. Restor
Section: B2B78
Branch Chart
J
Geometric Figures
Yes
Group 1A:
{A, F, L, J,
K}
Yes
No
Presence of circles
inside
No
Figure has
Group 2A: one circle Group 2B:
inside {A, F, J, K}
{L}
Pseudonym:
Yes
No
Lima sp.
All sides
are
Group 3A:
Group 3B:
congruent
{F, K}
{A, J}
Yes
No
The circles
are
Group 4B:
{K}
closer
together Pseudonym:
Kilo sp.
Foxtrot sp.
Group 4A:
{F}
Pseudonym:
No
Figure has
Group 6A: sides and Group 6B:
corners
{C, D, E, G, H,
{B}
Pseudonym:
I}
Bravo sp.
Yes
No
Figure has
Group 7A: strictly Group 7B:
three sides
{C, D, E, H, I}
{G}
Pseudonym:
Golf sp.
Yes
No
Figure has
strictly
Group 8A:
Group 8B:
{C, E, H, I}four sides
{D}
Pseudonym:
Delta sp.
Yes
Circles are
No
Group 5A: oriented
Group 5B:
horizontally
{A}
{J}
Pseudonym:
Pseudonym:
Alpha sp.
Yes
Yes
Group 9A:
{E, H}
Jaguar sp.
Yes
Group 10A:
{E}
Pseudonym:
Echo sp.
Group 1B:
{B, C, D, E, G,
H, I}
No
Two pairs of
opposite
Group 9B:
{C, I}
sides are
parallel
No
Yes
No
One pair of
sides
have
Group 11B:
Group 10B:Group 11A:
equal length
{C}
{I}
{H}
Corners form
right angles
Pseudonym:Pseudonym:
Pseudonym:
Hotel sp.India sp.
Charlie sp.
Bracketed Key
1a. Presence of circles inside the figure ............................. 2
1b. Absence of circles inside the figure .............................. 6
2a. Figure has one circle inside ........................... Lima sp. (L)
2b. Figure has two circles inside ..................................... 3
BIO102 (Systematics) Laboratory: Exercise 1
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3a. All sides are congruent ........................................... 4
3b. Only opposite sides are congruent ................................. 5
4a. The two circles are close together ................. Foxtrot sp. (F)
4b. The two circles are apart .............................. Kilo sp. (K)
5a. Circles are oriented horizontally ..................... Alpha sp. (A)
5b. Circles are oriented diagonally ...................... Jaguar sp. (J)
6a. Figure has sides and corners ..................................... 7
6b. Figure has no sides and corners ....................... Bravo sp. (B)
7a. Figure has three sides ................................. Golf sp. (G)
7b. Figure has more than three sides ................................. 8
8a. Figure has four sides ............................................. 9
8b. Figure has five sides ................................. Delta sp. (D)
9a. Two pairs of opposite sides are parallel ......................... 10
9b. Strictly one pair of opposite sides are parallel ................. 11
10a. Corners form right angles ............................. Echo sp. (E)
10b. Corners do not form right angles ..................... Hotel sp. (H)
11a. One pair of opposite sides have equal length ......... India sp. (I)
11b. No pairs of opposite sides have equal length ....... Charlie sp. (C)
Questions:
1. Is it possible to use different criteria for classifying objects?
Explain.
Yes. In the given example, classification of the twelve geometric
figures was executed by scrutinizing the observable characteristics,
starting from the most obvious (or the most shared) down to the most
technical. In doing so, the entire group was divided into subsets until
a certain characteristic will be able to separate a single element or
object from the group of objects.
2. What features could a person use to build a dichotomous key for
plants?
An aspiring botanist can start on the presence or absence of a
major organ, for example seeds, the first division. If it has seeds you
BIO102 (Systematics) Laboratory: Exercise 1
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could go on a second division by the presence of flowers, followed by
the type of cotyledon (monocot/dicot). This category, as well as the
other categories, could then be refined by first describing the basic
features of major organs, like the outline of leaves, habit growth of
stems, phyllotaxies, maximum height, overall texture, and other basic
descriptions of the stem, leaf, flowers, fruits, and seeds (if it has
one). The furthest subdivisions would scrutinize the finest details of
an organ, like the contrasting features of similar leaves in abaxial or
adaxial point of view.
3. How does a dichotomous key allow one to sort out an object more
accurately than if someone just describes the object?
By using dichotomous key, you are able to use a sequence of
statements sorted in a convenient and systematic method to describe any
object or organism. The key allows a reader to coherently merge
individual descriptions into a complete, unique statement as he or she
crosses one subdivision to another. Also, by limiting each division to
strictly two contrasting characters rather than multiple choices, you
would be able to understand the relationships and interrelatedness
between objects through their similarities and differences. Moreover,
you could easily transition each form of key to another, whether it may
be bracketed, indented, charted, or aided by technology such as using
big data to convert the descriptions into binary data.
4. What was the most difficult part of developing your dichotomous
key?
Personally, two parts were equally difficult: first, determining
related characteristics that contrast or differ from each other; and,
developing the flow of navigation in converting my branched chart to a
bracketed key. On the first few divisions, it was quite manageable to
group because the characters were too obvious. The crux occurred when I
was left with three or four objects to group, which are extremely related
like in Group 8A. Meanwhile, I had difficulty in navigation maybe because
I went for the bracketed key first before the branch chart. I thought I
could visualize the relationship better and work faster if I went for
the bracketed key first.
BIO102 (Systematics) Laboratory: Exercise 1
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