Lab #7: Introduction to the Kingdom Animalia Objectives: 1 ...

Lab #7: Introduction to the Kingdom Animalia
Objectives:
1. Understand hierarchical organization of animal complexity
2. Learn the differences between acoelomate, pseudocoelomate and coelomate organisms
3. Learn the advantages of cellular specialization to form tissues and organs
4. Learn how to classify organisms by their type of body symmetry
5. Understand the major differences between protostomes and deuterostomes
6. Learn and employ the directional terms used to identify body positions on different types
of organisms
Reading Assignments:
• Phylum Porifera (pgs. 387-388)
o Grantia (pg. 388)
o Structure of Sponges (pgs. 389-390)
• Phylum Cnidaria (pgs. 391-392)
o Metridium (pgs. 397-398)
• Phylum Platyhelminthes (pg. 401)
o Dugesia (pg. 402)
• Phylum Nematoda (pgs. 407-408)
o Ascaris (pgs. 409-410)
• Phylum Annelida (pg. 420)
o Class Oligochaeta (pgs. 421-422)
• Protostomes vs. Deuterostomes (pg. 441)
• Phylum Echinodermata (pgs. 441-443)
o Class Asteroidea (pgs. 444-445)
• Phylum Chordata (pg. 449)
• Subphylum Vertebrata (pg. 451)
o Class Osteichthyes (pg. 453)
• Body Terms (pg. 523)
• Body Axes (Fig 47.1 - pg. 524)
Introduction
The multicellular organisms that make up the 32 phyla of the kingdom Animalia have
evolved from the nearly 100 phyla produced during the Cambrian explosion about 600 million
years ago. During this time, an unprecedented variety of novel body plans and architectures
arose.
In the upcoming labs, we will examine the different levels of complexity and
organization in representative phyla of the kingdom Animalia. We will consider the

environmental constraints that led to the evolution of particular body plans and the adaptations
that certain animals evolved to survive in their environment.
In general, organisms from the kingdom Animalia are eukaryotic, multicellular, motile (at
least during certain developmental stages), heterotrophic and unlike plants, lack a cell wall.
Additionally, most animals reproduce sexually and have a characteristic pattern of embryonic
development. Similar to alternation of generations observed in previous phyla, organisms in the
Animal kingdom undergo stages of development, starting from the fusion of an egg and a sperm
and ending with a multicellular adult phase. While the morphology of the adult organism is
highly species-specific, the genes that regulate organismal development are often conserved
across species. In addition, the life cycles of members of Kingdom Animalia vary considerably,
i.e., stages may look completely different from each other (metamorphorsis), they may last for
different periods of time (hours vs. years) and can occur in different habitats (e.g. dragonflies -
adults live in air while larvae are aquatic).
NOTE: Make sure that you fully understand EVERY term used to
characterize animals because these terms will appear again in the upcoming
labs.
Task 1: Understanding Hierarchical organization of animal complexity
The table below describes the major patterns of organization of animal complexity. As you
examine the organisms today, note which level of organization is present in these animals.
1. Draw 1 organism per level of organization. The organisms that you should examine are
written in the table below. Make sure to note the Phylum, Genus and Species of the
organism that you examine.
2. Answer the questions below the table.

Level of
organization
Protoplasmic Cellular Cell-tissue Tissue-organ Organ-system
Description
Representative
group
All functions
are confined
to a cell
Protista
(NOT part of
kingdom
Animalia)
We will NOT
look at them
today.
Aggregation
of cells that
are
functionally
differentiated
Cells are
aggregated
into
patters/layers
= tissues
Different
tissues are
organized into
organs. More
specialized
than tissues.
Organs work
together to
perform a
coordinated
function
Parazoa Radiata Bilateria Bilateria
Example 1
a. Phylum
b. Genus
c. common name
a. Porifera
b. Grantia
c. Sponges
a. Cnidaria
b. Metridium
c. Sea anemone
a.
Platyhelminthes
b. Dugesia
c. Planarian
a. Chordata
b. Perca
c. Perch
Drawing of
whole organism
Slides
CS Grantia

Questions:
1. Can you suggest why, during the evolution of separate animal lineages, there has been a
tendency for complexity to increase when body size increases
2. Sponges have folded walls. What advantage could this trait have for the sponge
3. Could you think of other organisms or organ systems that also have similar folded structures
a. What advantages does folding provide for these organisms

Task 2: Differences between acoelomate and coelomate organisms
A major developmental event in bilaterally symmetrical organisms (see below) was the
development of a fluid filled cavity between the outer body wall and the gut (coelom). The
coelom created a tube-within-tube arrangement allowing space for visceral organs and an
increase in overall body size (Why). The coelom also provides support and aids in movement
and burrowing in some animals. However, not all organisms are coelomates, some lack a coelom
altogether and are called acoelomate (a = without) while others have a pseudocoelom (pseudo =
false). Read page 413 (exercise 38) to learn more about these organisms.
Examine the animals listed in the table below and fill out the missing sections.
Sample Organism Acoelomate Pseudocoelomate
Coelomate
(p. 402)
(p. 409)
(p. 421)
Phylum Platyhelminthes Nematoda Annelida
Genus Dugesia Ascaris Lumbricus
Common name Flatworms, planaria Roundworms Segmented worms,
Earthworms
Drawing of
Cross section
(slide)
If specimens are
available, dissect
them
longitudinally.
Draw what you see.

Questions:
1. Looking at the three representative specimens, what is the main difference between
coelomate, pseudocoelomate and acoelomate organisms
2. How are the organs and tissues organized differently in coelomates and acoelomates
Task 3: Body plans and symmetry
While the diversity of animal forms is great, the basic body plans can be categorized by the
presence and type of body symmetry. Make sure you understand the basic differences between
spherical, radial and bilateral symmetry (Examine figure 36.7 on pg 391)
Fill out the table below:

Symmetry type Description Example Phyla / Species
Spherical
This symmetry is found in
protozoa. Any plane passing through
the center divides the body into
equivalent/mirrored halves. Best suited
for floating and rolling.
Radiolaria (amoeboid protozoa)
WE WILL NOT EXAMINE THIS
TYPE OF SYMMETRY IN THIS
LAB
Asymmetrical
Sponge
Radial
Sea anemone
Bilateral
Perch

Questions:
1. Consider the environments where each type of body symmetry would be most efficient.
2. What is the advantage of having bilateral symmetry Can any particular task be achieved
more efficiently
a. Why would this type of symmetry lead to cephalization

3. Out of all the organisms you examined, is there a particular pattern between the
organisms that have bilateral symmetry Radial symmetry Make sure to consider
morphology.
Task 4: Developmental patterns in bilateral animals: Protostomes and Deuterostomes
Bilateral animals follow two major patterns of embryonic development. Based on these patterns
they are classified as either deuterostomes or protostomes. In deuterostomes, the blastopore (first
embryological opening) becomes the anus, while in protostomes the blastopore becomes the
mouth. Also, cleavage, the initial process of cell development after a zygote is formed is
different in the two lineages: In protostomes, cleavage is spiral, while it is radial in
deuterostomes.
The separation of the metazoans (multicellular animals) into two separate lineages, suggests an
evolutionary divergence of the bilateral body plan. This suggests that deuterostomes and
protostomes are separate, monophyletic lineages. For further information, please look at table
40.1 (pg. 441) in your lab manual.
Examine the animals noted under the “Example species” below and answer the questions below
the table.

Protostomes
(mouth first)
Deuterostomes
(mouth second)
Cleavage type Spiral Radial
Blastopore
Mouth
Anus
becomes
Representative
Phyla
Platyhelminthes, Arthropoda,
Annelida, Mollusca, Nematoda, and
smaller phyla
Chordata, Echinodermata, and
smaller phyla
Example species Nematoda - Ascaris Sea star – Asterias
Drawing
Task 5: Describing positions in bilaterally symmetrical animals
For a large portion of this course we will be examining bilaterally symmetrical animals from
various phyla. To be able to locate and refer to specific regions of animal bodies, we will use
terminology in your lab manual (pg. 523).
Practice with your group using directional terms to refer to a particular part/portion of the body.
You may use available specimens to practice. Make sure to use both radially and bilaterally
symmetrical animals.
The table below compares the terms used to describe animals with bilateral and radial
symmetries.

Radially-Symmetrical and Bilaterally-Symmetrical Animals
Bilateral
Radial
Direction Synonyms Direction Synonyms
Anterior
Rostral, Cranial,
Cephalic
Oral
Apical
Posterior Caudal Aboral Basal
Dorsal — Peripheral —
Ventral — Peripheral —
Left (lateral) Sinister Peripheral —
Right (lateral) Dexter Peripheral —
Medial — Same —
Proximal — Same —
Distal — Same —
Adapted from Wikipedia.
Task 6: Body axes charades – Run by the TA
To practice using the proper terminology to refer to different locations on the body, we
will play a game of charades. Your TA will divide the whole class into two groups. Each group
will be given a list of organs/ body parts. These lists will be different. Make sure not to share
your list with members from the other group.
Your group will choose a student from another group to describe one of the words on
your list to his/her group. The student will have 2 minutes to describe the word, using only the
words from the bilateral body axes (see table above). You cannot use words that describe the
function of the organs. For example, if the organ to be described is the heart, then you cannot say
that it pumps blood, but you can say that this organ is posterior to the head. If his/her group can
guess the right organ /body part, his/her team gets a point but if they don’t guess correctly, then
your team gets the point. Make sure to alternate the order of the teams guessing.