Download AP Biology Summer Assignment

AP Biology Summer Assignment
Welcome to AP biology. Our class is intense, with a lot of material that needs to be covered in a relatively
short amount of time. Please be aware that part of taking this class is commitment to being on time, on
task, and occasionally learning content on your own. We look forward to working with each one of you
next year!
We know the words “summer assignment” tends to send chills down any high school student’s spine, but
these assignments will be beneficial to you as we start the school year. The reason we are giving you a
summer assignment is to keep your mind sharp so you are ready to hit the ground running! It is also
important to realize that there is simply not enough time to cover the content of the course without a head
start.
Because AP Central has changed the Biology assessment we need to change the way we approach the
summer assignment. Please adhere to the following criteria when completing your assignments.
 It is important that you handwrite your work. This does not mean typing out your answers but
instead handwriting your responses in the space provided on the following worksheets.
 Work needs to be completed alone. You do not get to collaborate on the assessment so you
should not be collaborating on these assignments.
 Detail needs to be included in your answers. While we understand that you will need to use the
internet to review content, we also expect that you will properly cite your sources and give credit to
those individuals that aided in your understanding of the material.
The following worksheets and packets need to be completed no later than September 6th
1. Wallop Island Field Trip information (September 28th until October 1st): Not required and costs
the $400 to attend.
2. Graphing and Data Skills Practice Packet
3. Cell Structure and Function Packet
4. Classification Worksheet
5. Classification and Taxonomy Packet
6. Creating Phylogenetic Trees from DNA Sequences: Student Worksheet
If these assignments are lost you are able to obtain another copy be visiting our school webpage at
BWHS. Have a great summer and please contact us if you have any additional questions.
Mrs. Amber Poniatowski: [email protected]
Ms. Lauren Snow: [email protected]
Attention Parents and Guardians of Future Field Station Participants:
Each year we offer the students an opportunity to participate in the Chincoteague Bay (Wallops Island) Field
Station field trip. This year we schedule the trip for the beginning of the school year (September 28 until
October 1). Students are not required to attend the field trip. Those that choose to participate will owe
$400.00 which will be collected during the first week of school.
Below you will also find some answers to commonly asked questions. If you have other questions to email
Mrs. Poniatowski and/or Ms. Snow, or check out our website where there is more program information.
1. What is the Chincoteague Bay Field Station
We are a non-profit, educational institution. We have a board comprised of the Presidents of the
member universities. The Field Station was formed in 1968 to promote education and research in the
marine and environmental sciences and offer programs which range from elementary to university
levels, and adult learners.
2. How do I contact/get information about the Field Station?
There are several ways to contact us:
P: 757-824-5636, F: 757-824-5638, Email: [email protected] Website: www.cbfieldstation.org
3. Where is the Field Station located?
We are located on the Eastern Shore of Virginia, about 5 miles south of the Maryland/Virginia border.
We neighbor Chincoteague and Assateague Islands and the NASA Wallops Flight Facility.
4. How much money should my child bring on the trip?
All expenses during the program are covered in the student fee. We do have a Ship’s Store on campus
that has Field Station apparel and a variety of other souvenirs. Check with your group’s leader to see if
there are travel expenses or other activities planned for Free Night that may involve money.
5. How can I contact my son/daughter while they are at the Field Station?
Our office is open from 8am-4:30pm Monday thru Friday. You can call and leave a message with the
office staff and your child can return your call when they return from field trips. If it is a non-office
hours EMERGENCY, you can call our emergency cell phone which is carried by a staff member from
4:30pm thru 8am. The staff member on call can locate your child and let you speak directly to them.
The emergency number is 757-894-7708. Cell phone service can be intermittent because we are
located next to the NASA base but Verizon service seems to work the best.
Thank You,
Mrs. Poniatowski
Ms. Snow
What to Bring On Your Trip
Please be sure that all participants are adequately prepared for their trip. We have seen students unhappy in the field
because they were not wearing appropriate clothing. Please do NOT bring expensive items, snacks, or drinks other
than water.
Essential Items
 2 beach towels (for field trips)
 Bath towel, soap, personal toiletries
 Sunscreen
 Sleeping bag or sheets + blanket, pillow
 Refillable water bottle
 Rain gear (rain coat is a must, waterproof
pants are recommended if you have them)
 Pencil/pens
 Sunglasses/Hat
 Trash bags for laundry and wet clothes
 At least 2 pairs of socks for every day
Optional Items
 Binoculars
 Robe
 Camera
 Flashlight
 Alarm Clock
 Shower shoes
 Cards, books for free time
 Money for souvenirs
 Insect repellent
 Pack layers and bring an extra change of
clothing in case you get wet or dirty on one
of the field trips.
What you need for field trips:
Boat Trip:
 Sneakers or boots. A full shoe that laces. NO Keens or water shoes, etc.
 Wear layers. It is better to have too much clothing and not need it then to be cold with no jacket
Intertidal
 A bathing suit that will be worn under your clothing. Guys can wear just swim trunks with a t-shirt. Girls will want to
wear shorts and a t-shirt over the bathing suit. These clothes will get wet.
 Secure shoes that can get wet. Examples include Keens, Chacos, Tevas, water shoes or sneakers
 A change of dry clothing. This will be put over your wet bathing suit. A t-shirt and shorts are fine.
 A change of shoes
 A field towel and plastic bag for wet clothes and shoes
Dunes/Beach
 Wear shoes that can get wet and sandy. Your shoes from intertidal would work.
 Wear layers. The beach can be breezy.
Marsh
 A bathing suit that will be worn under your clothing
 A t-shirt that can get muddy
 LONG pants that can get muddy. NO exceptions.
 Sneakers or any shoes that tie that can get muddy. NO exceptions.
 A change of dry clothing. This will be put over your bathing suit.
 A change of shoes
 Field towel and plastic bag for wet / muddy clothes and shoes
Maritime Forest
 Comfortable walking shoes
 Wear layers to protect against weather and bugs
• For Organism Lab and your Free
Night you have the choice of what
to wear (dress for the weather).
The labs can be cold at night, so
bring a sweatshirt. You must
ALWAYS have shoes on when you
are walking around campus. Your
dorm is the only location where
you are not required to wear
shoes.
Name: _______________________________________________________ Date: _________ Block: _______
Graphing and Data skills practice Packet
Math and Statistics for AP Biology - Research the answer to the following questions
1. In designing an experiment or other scientific study, why do scientists sample from a population
rather than using an entire population?
2. Suppose you are designing an experiment to test the effects of nicotine on the heart rate of rats.
What are the disadvantages of having too small a sample size (i.e., testing on too few rats)? What
are the disadvantages of having too large a sample size (i.e., testing on too many rats)?
3. Explain the difference between discrete variables and continuous variables. Give an example of each.
4. Explain the difference between quantitative and categorical variables. Give an example of each.
5. What is a null hypothesis?
6. What are some steps that scientists can take in designing an experiment to avoid false negatives?
Graphing Practice
Graphing is an important procedure used by scientists to display the data that is collected during a
controlled experiment. Line graphs must be constructed correctly to accurately portray the data
collected.
A graph contains five major parts:
 Title
 The independent variable
 The dependent variable
 The scales for each variable
 A legend
•
The TITLE: depicts what the graph is about. By reading the title, the reader should get an idea
about the graph. It should be a concise statement placed above the graph.
•
The INDEPENDENT VARIABLE: is the variable that can be controlled by the experimenter. It
usually includes time (dates, minutes, hours, etc.), depth (feet, meters), and temperature
(Celsius). This variable is placed on the X axis (horizontal axis).
•
The DEPENDENT VARIABLE: is the variable that is directly affected by the independent
variable. Example: How many oxygen bubbles are produced by a plant located five meters below
the surface of the water? The oxygen bubbles are dependent on the depth of the water. This
variable is placed on the Y-axis or vertical axis.
•
The SCALES for each Variable: In constructing a graph one needs to know where to plot the points
representing the data. In order to do this a scale must be employed to include all the data points. The
scales should start with 0 and climb based on intervals such as: multiples of 2, 5, 10, 20, 25, 50, or 100.
The scale of numbers will be dictated by your data values.
•
The LEGEND: is a short descriptive narrative concerning the graph's data. It should be short
and concise and placed under the graph.
•
The MEAN for a group of variables: To determine the mean for a group of variables, divide the
sum of the variables by the total number of variables to get an average.
•
The MEDIAN for a group of variables: To determine median or “middle” for an even number of
values, put the values in ascending order and take the average of the two middle values.
Example: 2, 3, 4, 5, 9, 10. Add 4+5 (2 middle values) and divide by 2 to get 4.5.
•
The MODE for a group of variables: The mode for a group of values is the number that occurs
most frequently. Example: 2, 5, 8, 2, 6, 11. The number 2 is the mode because it occurred
most often (twice).
Problem A:
Using the following data to answer the questions below and then construct a line graph.
Number of bubble per minute
Plant A
Plant B
29
21
36
27
45
40
32
50
20
34
10
20
Depth in meters
2
5
10
16
25
30
1. What is the dependent variable and why?
2. What is the independent variable and why?
3. What are the mean, median, and mode of all three columns of data?
•
Depth :
•
Bubble Plant A.:
Mean_______ Median _______Mode____
•
Bubbles Plant B:
Mean_______ Median _______Mode____
Mean_______ Median _______Mode____
4. Title: ______________________________________________________________________________
__________________________________________________________________________________
Problem B:
Diabetes is a disease affecting the insulin producing glands of the pancreas. If there is not enough
insulin being produced by these cells, the amount of glucose in the blood will remain high. A blood
glucose level above 140 for an extended period of time is not considered normal. This disease, if not
brought under control, can lead to severe complications and even death.
Answer the following questions concerning the data below and then graph it.
Time After Eating (Hours)
0.5
1
1.5
2
2.5
3
4
Glucose mL per Liter of Blood
Person A
Person B
170
180
155
195
140
230
135
245
140
235
135
225
130
200
1. What is the dependent variable and why?
2. What is the independent variable and why?
3. What title would you give the table above?
4. Which, if any, of the above individuals (A or B) has diabetes?
5. What data do you have to support this conclusion?
6. If the time period were extended to 6 hours, what would the expected blood glucose level for Person B?
Explain why.
Title:
__________________________________
_______________________________________________________________________________________
Problem C:
Temperatures were obtained in November in a fairly arid area of Nevada. At two different sites,
temperature readings were taken at a number of heights above and below the soil surface. One site
was shaded by a juniper (a plant) whereas the other was not.
Condition
Air
Air
Air
Air
Soil Surface
Humus
Mineral
Mineral
Temperature (OC)
Height in cm from soil surface
150
90
60
30
0
-6
-15
-30
Beneath Forest cover
Unshaded Field
18
18
18
18
16
12
9
7
20
21
20
21
33
19
15
12
Construct a line graph, plot the data, and give an appropriate title in the space below.
Problem D:
A researcher interested in the disappearance of fallen leaves in a deciduous forest carried out a field
experiment that lasted nearly a year. She collected all the leaves from 100 plots scattered throughout the forest.
She measured the amount of leaves present in November, May and August. The percentages reflect the
number of leaves found, using the November values as 100 percent. Complete the table by calculating the
missing percentages.
Collection Date
Ash
Beech
Elm
Hazel
Oak
Willow
November
4271g
3220g
3481g
1723g
5317g
3430g
100%
100%
100%
100%
100%
100%
2431g
3190g
1739g
501g
4401g
1201g
57%
91%
______%
_______%
83%
35%
1376g
2285g
35g
62g
1759g
4g
32%
71%
______%
_______%
33%
0.1%
May
August
Construct an appropriate line graph for the ash and elm leaves on the graph below.
Problem E:
A species of insect has been accidentally introduced from Asia into the US. The success of this
organism depends on its ability to find a suitable habitat. The larval stage is very sensitive to
changes in temperature, humidity and light intensity. Expose to situations outside the tolerance
limits results in a high mortality (death) rate. Study the data table below.
Temperature (oC)
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Relative
Light
Mortality (%) Humidity (%) Mortality (%) Intensity (fc) Mortality (%)
100
100
80
300
0
16
80
90
10
400
0
17
30
80
0
600
10
18
10
70
0
800
15
19
0
60
0
1000
20
20
0
50
50
1200
20
21
0
40
70
1400
90
22
0
30
90
1600
95
23
20
20
100
1800
100
24
80
10
100
2000
100
25
100
0
100
2200
100
Plot line graphs for the effects of temperature and humidity on mortality rates.
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Name: ______________________________________________________________________ Date: _________________ Block: _____________
Cell Structure and Function
Research the following structures and/or organelles found below using a variety of online resources, this does not include your friends or fellow
students. In your own words describe the function of each structure. Structures underline should also include a diagram. These functions should go
above and beyond the definitions that were given during first year biology. You will need to commit these structures to memory. Every Wednesday
you will be assessed on this material by taking a quiz (1st Quarter: Matching, 2nd Quarter: Multiple Choice Questions, and 3rd Quarter: Free
Response).
Structure
Nucleoid
Nuclear envelope
Cytoplasm
Organelle
Cytosol
Plasma membrane
Endomembrane system
Function
Vesicles
Central vacuole
Cytoskeleton
Nucleus
Nucleolus
Ribosomes
Rough endoplasmic reticulum
Smooth endoplasmic reticulum
Golgi apparatus
Lysosomes
Peroxisome
Contractile vacuole
Mitochondria
Chloroplast
Flagella
Cilia
Cell wall
The Evolution of Cells
Click on the following link: http://learn.genetics.utah.edu/content/cells/organelles/ and answer the questions that follow.
1. Describe how the Earth’s atmosphere has changed over time. How has this impacted the type of organisms that evolved?
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
2. Describe how the endosymbiotic theory got its name. __________________________________________________________________________
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
3. “Mitochondria and chloroplast have striking similarities to bacteria cells.” Explain what evidence is used to support this statement.
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
4. Describe the pattern of inheritance for mitochondrial DNA (mtDNA). _______________________________________________________________
________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________
Name: ______________________________________________________ Date: _________ Block: ________
Classification Worksheet
Use online resource to answer the following questions. This packet will serve as your notes on these terms.
1. Draw a gastrula and label the blastopore and tissue layers. Define the terms diploblastic and triplobastic.
What significance do these terms play in the level of complexity in an organism?
2. Contrast protostomes and deuterostomes. List two examples of each. ____________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
3. Define what the following types of symmetry and list two examples of each.
•
Asymmetry
•
Radial Symmetry
•
Bilateral Symmetry
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________ 17
________________________________________________________________________________________
4. Describe cephalization? _________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
5. There are three main types of body cavities found in animals. Define the following and list two examples of
each.
• Acoelomate
• Psuedocoelomate
• Coelomate
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
Animal Development: We're Just Tubes - Crash Course Biology
Watch the following video and take notes on information not covered in the questions above:
https://www.youtube.com/watch?v=k_9MTZgAhv0
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Name: ____________________________________________________ Block: _______ Date: ____________
Creating Phylogenetic Trees from DNA Sequences: Student Worksheet
Click on the following link: http://media.hhmi.org/biointeractive/click/Phylogenetic_Trees/01.html
Answer the following questions as you proceed through the activity slides.
1. Briefly explain how scientists draw relationships between organisms based on shared anatomical features.
_____________________________________________________________________________________
_____________________________________________________________________________________
2. How are DNA sequences used to deduce evolutionary relationships? ______________________________
_____________________________________________________________________________________
3. What is one advantage of building phylogenetic trees using DNA comparisons rather than anatomical
features? _____________________________________________________________________________
_____________________________________________________________________________________
4. Watch the video clip on slide 3 and then draw a simple tree illustrating the evolutionary relationships
between gorillas, chimpanzees, humans, and orangutans.
5. Watch the short video on slide 4. How has biotechnology affected the process of building phylogenetic
trees from DNA sequences? ______________________________________________________________
_____________________________________________________________________________________
6. What do evolutionarily related organisms share? ______________________________________________
7. What are two common types of mutations? __________________________________________________
8. Watch the short animation on slide 6 and describe a SNP. ______________________________________
_____________________________________________________________________________________
9. Watch the short animation on slide 7 and described an indel. ____________________________________
_____________________________________________________________________________________
10. Explain the difference between distantly related and closely related organisms in terms of their DNA
sequences. ___________________________________________________________________________
_____________________________________________________________________________________
11. What does it mean to compare “apples to apples” when referring to DNA sequences from different
organisms? ___________________________________________________________________________
_____________________________________________________________________________________
12. Watch the short animations on slide 10 and explain what is meant by “aligning” DNA sequences.
_____________________________________________________________________________________ 19
_____________________________________________________________________________________
13. How is a SNP identified in an alignment? ____________________________________________________
_____________________________________________________________________________________
14. How is an indel identified in an alignment? ___________________________________________________
_____________________________________________________________________________________
15. Look at the information on slide 15. From left to right, identify the base in each box as an indel or a SNP.
Write your answers in the spaces below.
Box 1 (left) _________
Box 2 (center) _________
Box 3 (right) _________
Now click on each box and check your answers to question 15 above.
16. Watch the video clip on slide 17. How can you identify the two sequences that are most similar?
_____________________________________________________________________________________
17. Watch the video clip on slide 18 and describe the link between the length of the line and time.
_____________________________________________________________________________________
18. What is surprising about the placement of hippos on the phylogenetic tree?
_____________________________________________________________________________________
19. Define a branch point (also called a node) on a phylogenetic tree and describe what it represents.
_____________________________________________________________________________________
_____________________________________________________________________________________
20. What is the root? _______________________________________________________________________
_____________________________________________________________________________________
21. What does the node closest to the root represent? ____________________________________________
22. Describe what an unrooted phylogenetic tree represents. _______________________________________
_____________________________________________________________________________________
23. On slides 22 and 23, notice how phylogenetic trees can rotate around nodes and have different shapes.
Notice the relationships between the organisms do not change.
24. Using the information on slide 24, explain how DNA evidence supports the known biology of the seven
cone snails. ___________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
25. Write three conclusions drawn from the information provided in this Click and Learn:
a. __________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
b. __________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
c. __________________________________________________________________________________
__________________________________________________________________________________
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Name: _______________________________ Date: _____________ Block:
_________
Classification & Taxonomy Activity
The diversity of life on Earth is astounding. Each organism has a unique body plan
which allows it to survive and adapt to its surroundings. With such an abundance of
species, classifying organisms into different categories is necessary in order to
assign each a scientific name and to understand its evolutionary history. The
diversity of living organisms is overwhelming, but after further research and
observation, many likenesses appear. These similarities become the basis for
taxonomists to organize organisms into their appropriate hierarchal categories.
Animals are classified into categories called taxa according to their body plan,
phylogeny, and other similar characteristics. There are seven principle levels that
organisms can be placed into: Kingdom, Phylum, Class, Order, Family, Genus, and
Species. All animals are in the Kingdom Animalia. As you move from kingdom to
species, the animals that are grouped together become more closely related at each
succeeding level.
The next level after Kingdom is Phylum, which is the main focus of this activity. Even
though there are approximately thirty-five phyla within the animal kingdom, 98
percent of all animals are classified into eight of them. To get even more specific,
seven of the eight phyla are invertebrates. Invertebrates comprise most of the animal
kingdom, with almost 75 percent of all animals on earth being insects. They out
number humans by a million to one!
From Phylum, animals are then broken down into more specific categories. For
example, a shark, a bird, and a human are all in the Phylum Chordata. What
similarities do these animals have? Taxonomists agree that all these animals have a
similar internal skeleton. However, these animals would not be grouped in the same
Class. This process would continue until the animal is classified down to Species.
Note that Sub-phyla do exist, and, there are visible differences not only amongst the
different animal phyla, but also within each phyla.
Procedure:
1. Review the phyla descriptions provided, highlight and take annotated notes on the
characteristics from each phylum. http://faculty.bucks.edu/specpop/annotate-ex.htm
2. The table on page ten provides a reference list of main characteristics for the eight
phylum below. Using the information in this grid, list the characteristics applicable to
each phylum in the chart provided on page eleven of this activity. The end product
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will be a comparison of the main characteristics of each phylum. Note that some of
the characteristics are used multiple times.
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Porifera
Sponges
The Phylum Porifera consists only of sponges. These animals are entirely aquatic;
98% are found only in marine environments and a small percentage are found in
freshwater lakes and streams. Sponges are considered the oldest and of the animal
phyla. Translated from Latin, Porifera means “pore bearer.” Sponges play an
important role in aquatic ecosystems, filtering particles, including bacteria, out of the
water. The surface of a sponge is covered with a skin that is one cell thick. This skin
is penetrated by numerous small pores and a few larger openings. These larger
openings are the entrances and exits for a complex system of canals and chambers
through which the sponge pumps a current of water. The body of a sponge, between
this system of canals, is a loose assemblage of cells that secretes a supporting
skeleton of collagen fibers and mineral spicules made of glass or calcium carbonate.
This body carries out the process of growth, repair, nourishment, and reproduction.
Sponges can filter water at a rate equal to their entire volume in less than a minute.
As the sponge pumps in water at this rate, it captures tiny food particles as small as
a single micron in diameter. Choanocytes are specialized flagellated cells, also
called collar cells that enable sponges to pump the water. Since sponges are filter
feeders they often have to filter over a ton of water to secure just a single ounce of
food.
Sponges reproduce asexually by fragmentation or budding, sexually using eggs and
sperm, or they are hermaphroditic—a single species with both male and female
gametes. Their commercial importance includes use as bath sponges as well as
being tested for possible anti-cancer drugs or antibiotics. Sponges provide a microhabitat for other organisms and they aid in cleaning their aquatic environments.
Since sponges are considered the simplest of the all animal phyla, they are
important subjects for analyzing the evolution of animals. Studies indicate that the
Phylum Porifera is at the base of the animal phylogenetic tree.
Features:
* Asymmetrical
* Organized as an assemblage of different kinds of specialized cells, e.g. collar cells
* No tissues
* Skeleton lacking or made of spicules
* Depends on system of water currents for food and oxygen
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Cnidaria
Jellyfish, Corals, Anemones, Hydras
The phylum Cnidaria includes jellyfish, corals, sea pens, sea anemones, and hydras.
This phylum contains the most venomous marine creature; the Australian box
jellyfish. It is known to kill more people than sharks, crocodiles, and stonefish
combined. It can cause shock and heart failure within minutes. Sea turtles are able
to prey upon the box jellyfish because they are not affected by the venom. Most
cnidaria alternate between two different body forms throughout their life: a freeswimming form, called the medusa, and a stationary form, called the polyp. Both
body types follow the same basic plan. They are radially symmetrical with three
layers of tissue. Each species has a single opening that serves as both the mouth
and the anus. That shared opening is usually surrounded by a ring of tentacles,
allowing the animal to capture prey from all directions.
Cnidarians have a defined top and bottom and two distinct layers of tissue: an
epidermis outer layer and an internal gastrodermis. Between these tissue layers is a
layer called the mesoglea. In the form of a medusa, the mesoglea is an elastic, clear
jelly with fibers made of protein called collagen. The mesoglea aids in locomotion by
elastically recoiling in response to muscle contractions. Cnidarians’ muscles and
nerves are located at the base of the tissue layers. The internal space, surrounded
by the layers of tissue and mesoglea, is the gut or gastrovascular cavity.
In order to capture prey, cnidarians have stinging cells. Located in their tentacles,
these stinging cells, called cnidocytes, contain tiny, often toxic harpoons, called
nematocysts. Triggered by touch or certain chemicals, nematocysts fire out of the
cnidocyte housing at lightning speed. Some hydra can fire these harpoons with an
accelerated force equal to 40,000 times the acceleration of gravity. That’s 10,000
times the acceleration force of a space shuttle. Once the nematocyst hits it mark,
usually lethal poisons are injected into the prey. The combination of defined tissues,
muscles, nerves and a gut allowed ancestral cnidarians to be the first animals on the
planet to show animated behavior. The name Cnidaria comes from the Latin word
meaning “nettle.”
Features:
* Two tissue layers with nerve and muscle tissues
* Nematocysts - structures contained in special cells called cnidocytes or cnidoblasts
that can act in both offense and defense
* Two main life forms - free-swimming medusa (e.g. jellyfish) or stationary polyp (e.g.
anemone)
* Radial symmetry
* Extracellular digestion in gastrovascular cavity
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Platyhelminthes
Flatworms
This particular phylum is one of the lesser-known groups and includes such animals
as freshwater planaria, colorful marine polycads, and parasitic tapeworms and
flukes. The name Platyhelminthes in Latin means “flat worm.”
Fossilized worm tracks in the early Cambrian period hint at the origin of this body
plan. While the classification of Platyhelminthes remains controversial because of
the diversity within each class included in this phylum, flatworms share distinctive
features. They are bilaterally symmetrical with a defined head and tail region and a
centralized nervous system containing a brain and nerve cords. Clusters of lightsensitive cells make up what are called eyespots. The head region of the flatworm
also contains other sense organs which are connected to the flatworm’s simple
brain. Like most animals, with the exception of sponges and cnidarians, flatworms
possess three tissue layers making them triploblastic. The middle tissue layer, called
the mesoderm, helps form true organs including reproductive organs such as
ovaries, testes, and a penis.
Flatworms are hermaphroditic and capable of sexual and asexual reproduction. They
have no circulatory system or body cavity (coelom), but they do have an excretory
and digestive system. Passive diffusion through the skin supplies oxygen to their
body parts. The highly branched gastrovascular cavity distributes nutrients to their
cells.
Most species of flatworms are parasitic—they have evolved protective skin coverings
and elaborate attachment mechanisms to allow them to live inside their hosts.
Features:
* Bilaterally symmetrical with a head and tail
* Centralized nervous system
* Three tissue layers
* Acoelomate
* No circulatory system
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Annelida
Polychaetes, Earthworms, Leeches
The Cambrian period began approximately 543 million years ago. Of the eight major
phyla, two were known from fossils at this time - Porifera and Cnidaria. Shortly
thereafter, a profuse radiation of fossils representing the other animal body plans
occurred over a relatively brief span of about 10 million years. The rest of the animal
phyla evolved during, or shortly after, this evolutionary explosion of new life forms in
the Cambrian period.
The Annelid body plan is equal in complexity to that of chordates. Annelids are
bilaterally symmetrical; they contain three tissue layers and are coelomates. The
coelom surrounds a one-way muscular digestive tract that runs from the mouth to
the anus and includes a pharynx, intestine, and other structures. Annelids have a
closed-circulatory system and a segmented central nervous system that includes a
simple brain located in the head region.
One of the distinctive traits of an annelid is that it has segmentation—Annelida
means “little ring” in Latin. Each segment has a number of bristles, called setae,
which help the worm move. The evolution of segmentation is an important
development for the annelids because it enabled the specialization of different body
regions. Fluid-filled coelomic compartments were another important adaptation for
annelids because it insulated the gut from locomotor muscles and provided a
hydrostatic skeleton enabled these worms to swim and burrow.
Features:
* Elongate, bilateral body with segmentation
* Triploblastic
* Well-developed coelom
* Closed circulatory system
* Bristle-like structures called setae projecting from body (except in leeches)
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Arthropoda
Crustaceans, Spiders, Millipedes, Centipedes, Insects
Of all the phyla in the animal kingdom, Arthropoda is by far the largest and most
diverse. All arthropods have segmented bodies and are covered in a hard, yet
flexible exoskeleton. Their muscles attach to the inside of the exoskeleton.
The name Arthropoda means “jointed foot” and refers to their jointed appendages. In
order to grow, arthropods must shed their chitonous exoskeleton periodically in
process called molting. When an arthropod goes through specific developmental
stages it is called metamorphosis. Metamorphosis can bring on radical changes in
body design; for example, a dragonfly begins its life in a pond as a swimming larva
and then changes into a completely different-looking winged adult.
Arthropods, like all animals, originated in the sea, but became the first animal group
to live on land and take to the skies. This is likely because arthropods demonstrate a
genetic predisposition to adapt to changing conditions. The diversity and success of
the arthropods can be attributed to their versatile body plans. Key features of which
lie in the development of myriad types of appendages: antennae, claws, wings,
shields, and mouthparts. These characteristics enabled arthropods to exploit nearly
every niche on Earth.
Features:
* Hard exoskeleton made of chitin and protein
* Jointed appendages
* Segmented body
* Grows through metamorphosis
* Triploblastic
* Open circulatory system
* Reduced coelom
* Bilaterally symmetrical
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Mollusca
Clams, Snails, Slugs, Nautilus, Octopus
Animals in this phylum—chitons, snails, slugs, clams, squid, and octopi—show an
amazing degree of diversity. All molluscs have soft bodies. In fact, the name Mollusc
means “soft” in Latin. Most molluscs are covered by a hard shell, which is secreted
by a layer of tissue called the mantle; the mantle overlays the internal organs of the
mollusc. Molluscs also have a strong muscular foot, which is used for movement or
grasping. They have gills, a mouth and an anus. One feature unique to molluscs is a
file-like, rasping tool called a radula. This structure enables them to scrape algae off
rocks, to drill through the hard shells of their prey, or catch fish.
The diversity of molluscs demonstrates how a basic body plan can evolve into a
variety of different forms that enable survival in specific environments. For example,
the hard shell in a land-dwelling snail is relatively large and serves to protect the
animal. However, in the fast-swimming squid the shell has been reduced to a small
pen-shaped structure.
Features:
* Rasping organ called a radula—present in all groups except bivalves and
Aplacophora
* Muscular foot—used for locomotion and other tasks
* A sheath of tissue called the mantle that covers the molluscs’ body and can secrete
the shell (if there is one)
* A mantle cavity that houses the gills or lungs
* A calcium shell is present in most molluscs. Some molluscs have greatly reduced
shells: squid. Others have completely lost the shell feature: slugs, nudibranchs,
and octopi.
* Coelomate
* Triploblastic
* Most show bilateral symmetry
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Echinodermata
Sea stars, Sea Lilies, Sea Urchins, Sea Cucumbers, Brittle Stars
There are about 6000 living species belonging to the phylum Echinodermata. The
bodies of echinoderms are made of tough, calcium-based plates that are often spiny
and covered by a thin skin. This tough body is how they get their name—
Echinoderms (echino-spiny, derm-skin).
Echinoderms are exclusively marine animals. This phylum includes sea stars, sea
lilies, urchins, sea cucumbers, sand dollars and brittle stars. Echinoderms do not
have a distinct head and tail. Instead, many Echinoderms begin life as bilaterally
symmetrical larvae and later develop into organisms with pentaradial symmetry.
The mouths of most Echinoderms are located on the underside of their bodies.
Echinoderms move, feed, and respire with a unique water-vascular system ending in
tube feet. Sea stars use their tube feet to slowly pry open clams, mussels, and other
prey. Some sea stars can even extrude their stomachs from their bodies and insert
them into the tiny openings between the two shells of bivalves and digest the soft
bodies inside.
An interesting ability of both sea stars and sea urchins is regeneration. If body parts
such as legs, tube feet, or spines are lost they can grow back. Most echinoderms are
either stationary or slow-moving but nevertheless prominent members of the marine
environment.
Features:
* Triploblastic
* Coelomate
* Internal skeleton made of small calcium plates
* Five-part radial symmetry
* Water-vascular system that operates the tube feet
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Chordata
Tunicates, Lancelets, Vertebrates including Amphibians, Reptiles, Mammals
The Phylum Chordata includes a wide range of animals from tunicates that look like
sponges, to vertebrates including fishes, frogs, snakes, birds, and humans. Despite
this diversity most all chordates share certain characteristics at some point in their
development. One of these features is a stiffening rod called a notochord that, in the
vertebrates, is later replaced by a bony vertebral column. In most adult vertebrates
the notochord remains as a disk between the vertebrae. Another chordate feature is
the dorsal nerve cord that becomes the spinal cord and brain. Also included in the
chordate body plan are structures called pharyngeal gill slits; these skeletal elements
function as jaws and jaw supports, and can take on a variety of other functions.
The most conspicuous group of Chordates is the subphylum Vertebrata. Chordates
have internal skeletons that enable chordates to grow continuously with no need for
molting and can support a large mass. This feature has allowed some vertebrates to
grow to large sizes; consider the African elephant or the giraffe. This internal
skeleton is also credited with enabling the powerful movements of swimming fish.
A major embryonic development in the evolution of vertebrates is the appearance of
the neural crest. The neural crest is a specialized population of undifferentiated,
migratory cells that are correlated with the emergence of vertebrate jaws, skull, and
a number of other structures that lead to more complex organisms. Another feature
that likely added to the complexity of vertebrates was the duplication of HOX genes.
Scientists speculate that additional copies of these genes that control organism body
plans provided additional genetic material available to evolve a more complex
organism. Both of these aforementioned features likely offered new opportunities for
adaptation.
Vertebrates fall into two main categories: fishes and tetrapods. Tetrapods developed
from a distinct lineage of fishes that possessed internal fin bones. These structures
eventually aided in supporting the weight of animals on land and laid the foundation
for arms and legs and the first amphibians. The development of a shelled amniotic
egg enabled tetrapods to remain on land and develop into reptiles, birds, and
mammals. From an ancient reptilian ancestor, two groups of animals, mammals and
birds, independently developed the capacity to maintain a constant body
temperature.
Features:
* Notochord
* Single, dorsal, tubular nerve cord
* Phalangeal pouches
* Segmentation
* Post-anal tail
* Bilateral symmetry
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Characteristic Table:
Bilateral phylum
that added
segmentation
Most have a
calciumcarbonate shell
Five-part radial
symmetry
Specialized cells,
but not organized
into organs or
tissues
Mantle of tissue
covering the body
Hollow body
cavity for food
Three tissue
layers, but no
body cavity
Fluid-filled
compartments
used for
locomotion
Jaws and skulls
important in their
evolution
Complete
digestive tract
with two ends
Most members
are parasitic
Water flows
through its body,
full of canals
Pioneered jointed
legs
First phylum to
venture into the
air
Some have
stinging
structures
(nematocysts)
Increased
complexity
made possible
by much more
DNA
Body design
basically a tube
within a tube
Tube feet used
for locomotion
First muscle and
nerves
Most have inside
skeleton of bones
All members
live in the ocean
Some of the
simplest animals
with bilateral
symmetry
Digestive tract
with the entrance
being the exit
All have
notochord; most
have backbone
Champions of
variations in
appendages
More species
than any other
phylum
Some spines are
little pinchers
(pedicellaria)
Some nonswimming polyps
Some free-drifting
medusae
Some propel,
using their siphon
as a water jet
Muscular “foot”
used to slide,
dig or jump
No locomotion;
stationary animal
Tubular mouth
(pharynx) at midbody
Phylum to which
humans belong
Hard but flexible
bodies with
interlocking plates
under their skin
Spicules act as
a skeleton to
give it structure
Feeding device
like a toothed,
rasping tongue
(radula)
No symmetry or
consistent body
shape
Exoskeleton
made of chitin
and protein
Their active
burrowing has
affected global
climate
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Name _________________________________________________________________Date_____________________ Block: ________
Classification & Taxonomy Activity — Answer Sheet
Characteristics from the chart above need to be WRITTEN in the space provided below
Porifera (5 characteristics)
Cnidaria (6 characteristics)
Platyhelminthes (5 characteristics)
Annelida (5 characteristics)
Arthropoda (7 characteristics)
Mollusca (6 characteristics)
Echinodermata (6 characteristics)
Chordata (7 characteristics)