Date: September 20, 2022
Lab: 01
Title: Ecology-Dichotomous Keys
Aim: To construct a spider key and a numerical key from drawings of four (4) plants and
four (4) animals.
Material(s)/Apparatus: four (4) plants, four (4) animals, ruler, pen, pencil, binder and
pages
Diagram: Drawing of four (4) plants and four (4) animals.
Method: 1. The scientists will walk around the school compound and observe four (4) plants
and four (4) animals.
2. Make drawings, to construct a spider key of plants and animals.
3. Make drawings of each animal and plant.
4. Use the drawings, to construct a numerical key of plants and animals along
with a spider key for the same.
Observation:
(Cassia Fistula, Razor Grass, Dandelion and Sleep and Wake)
The future aspiring scientist had observed the “characteristics of the plants”- (leave
arrangements) and deduced that the foliole are made up of a compound which is in fact not
leaves but leaflets. Additionally, that the leaves were arranged on stem possessing nonmutagenic phyllotactic pattern of each plant.
STEM
FLOWERING/NON-FLOWERING
ROOT
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Arthropods (Butterfly, Dragonfly, Spider and Ant)
This hypothesis suggests that the insect's wings developed from paranotal lobes. Futhermore,
supporting this hypothesis is the tendency of most insects, when there startled while climbing
on branches in which their theory of escape is by dropping to the ground or in other words
fake a dramatic death.
BODY PARTS-SEGMENTED/……
REACTION WHEN ENCOUNTERING HUMANS AND OTHER ANIMALS
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Discussion:
A dichotomous key is a tool created by scientists to help scientists and laypeople identify
objects and organisms. (Biology Dictionary, Biologydictionary.net, 20 Mar. 2017)
A dichotomous key is usually used for:

Identifying and categorizing organisms

Helping students easily understand harder scientific concepts

Organizing large amounts of information to make identification of an organism much
easier
Reflection: The future aspiring scientist was able to acquire a clear understanding of the
“known organisms”- (plants and animals) which were collected and understudied with
regards to their feathers, unique scientific names and linkages to other kinds of groups.
Notwithstanding, the people who would be exposed to this document that maybe new to the
study of ecology can acquire a fair understanding of organisms, their scientific names, parts
and classification.
Thus, the future aspiring scientist was able to garnered information of the species of
plants and animals; and their “classifications”- (whether there are related to single or closely
related-group organisms).
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This hypotenuse had made the aspiring scientist really understand the declaration of both
plants and animals and obtain knowledge on their physical features and their well-being
Conclusion: The aim of this experiment was to construct a spider key and a numerical key
from drawings of four (4) plants and four (4) animals for the purpose of observing the
characteristics of each living organisms that were collected from the “natural
environment”-(school). This task helped the future aspiring scientist to identify and category
organisms; make connections between known organisms with that of unknown organisms
which were evolved overtime. While, understanding scientific concepts of the understudied
organisms.
Numerical Key for plants
1. leaf dicotyledonous leaves …. go to 2
Has monocotyledon …. go to 4
2. Has flowers…. Cassia Fistula
Does not have flowers …. go to 3
3. Has Razors…. Razor Grass
Does not have razors…. cassia fistula, sleep and wake, Dandelion
4. Has a soft, light texture… Dandelion
Does not have a soft light texture…go to 5
5. Has Tap Root…. Razor Grass, sleep and wake
Does not have Tap Root…. Cassia Fistula
Numerical Key for Animals
1. Wings…Butterfly, Dragonfly
No Wings…go to 2
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2. Hard plates on their back…Spider
No hard plates on their plants…go to 3
3. As Antennae…. Butterfly, Dragon Fly, Ant
No Antennae… Spider
5. Walks on 4 Legs…Butterfly, Dragonfly
Walks on 8 legs…Spider, Ants
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