Tommy Smith

Dr. Snyder

9th

Grade

2011-2012

1. Scientific Method

2. Microscope Lab

3. Microscope Handout

4. Animal Cell Coloring

5. Plant Cell Coloring

6. Organelle Flashcards

7. Animal and Plant Cell Modeling

8. Mitosis Simulation Lab

9. Mitosis Drawing

Animal and Plant Cell Modeling

I. Purpose: 1. Recognizing the structural differences between plant and animal cells; 2. Understand

the function of each organelle; 3. Create a 3D cell model; 4. Gain a better perspective on the size

of each cell type and its components

II Materials: Plant Cell: Cupcake, Green Jello, Rectangular Pan, Blue and Green Jolly Ranchers,

Twizzlers, Fruit by the Foot, Jelly Beans, Flat Jolly Ranchers, Jaw Breakers, Tupperware, Sweet

Tarts, Beaker

Animal Cell: Cupcake, Blue Jello, Circular Pan, Red and Purple Jolly Ranchers, Twizzlers,

Fruit by the Foot, Jelly Beans, Flat Jolly Ranchers, Sweet Tarts, Jaw Breakers, Beaker

III. Procedure

Plant Cell

Prepare the Jello as instructed on the packaging. Before the Jello solidifies, place all the candies

in. Turn the Tupperware container upside down and put it in also. Place the cupcake in the

beaker and put it in as well, making sure the cupcake stays dry. Refrigerate for the amount of

time prescribed by the box.

Animal Cell

Prepare the Jello as instructed on the packaging. Before the Jello solidifies, place all the candies

in. Place the cupcake in the beaker and put it in as well, making sure the cupcake stays dry.

Refrigerate for the amount of time prescribed by the box.

IV. Data

A. Drawing of Plant Cell

See Separate Sheet

B. Drawing of Animal Cell

See Separate Sheet

V. Conclusion

1. Was the cell you created prokaryotic or eukaryotic? How can you tell?

The cell was eukaryotic. I could tell because It had a membrane-bound nucleus and organelles.

2. List three ways in which your cell model could be more accurate.

The candies dissolved in the jello mix and so perhaps a way could be found to make them not

dissolve. There could be a way to differentiate between the cell membrane and the cell wall

besides the shape. Finally, we could use something more transparent than the jello is.

3. Create a Venn Diagram that shows some of the differences and similarities (three each)

between a plant and animal cell.

Animal Cell Both Plant Cell

No cell wall Cell membrane Cell wall

No chloroplasts Membrane-bound Nucleus Chloroplasts

No large vacuole Contain Cytosol Large Vacuole

4. One of the main differences between a plant and animal cells is that an animal cell lacks a

cell wall. Research and explain how this slight physical difference has altered the physical

characteristics and development of animal cells.

This has made animal cells more flexible than plant cells and has also made it easier to move.

Animal cells lack the structure and protection that the cell wall provides.

5. Describe the effect that another one of these differences has had on the development of plant

or animal cells.

Animal cells lack chloroplasts. Plant cells are able to produce their own food and therefore do

not have to be mobile in order to find it. Plant cells therefore have to go find food.

6. Create an analogy relating all the parts of a plant or animal cell to something of your

choosing.

An animal cell is similar to a farm. The mitochondria are the combine harvesters which harvest

the crops. The nucleus is the farm house from which the commands of the farmer are issued.

The cell membrane is the gate and fence of the farm which lets things in and out. The lysosomes

are the birds that eat the dead plants and seeds. The endoplasmic reticulum is the truck that

carries all the crops from place to place. The Golgi apparatus is the processing plant after which

the crops leave the farm. The ribosomes are the farm hands which help produce the crops.

7. Name three ways in which cells are able to control their movements.

They move by using cilia, flagella, and by pseudopodium.

8. Identify what materials were used to represent the various parts of your cell model. Where

these good representations? Why or why not?

The cupcake represented the nucleus, but it was not a good representation because it is not

multi-layered like the nucleus is. The jello is a good representation because the cytosol has a

gelatin-like texture. The pan was a good representation of the cell wall because of its rigid

structure but not of the cell membrane because is is completely inflexible. The Jolly Ranches

were a good representation of both the chloroplasts and the mitochondria. Because they were the

same relative size and shape. The Twizzlers were not a good representation of the cytoskeleton

because they are too relatively large. The Fruit by the Foot are a good representation

because they are the same relative size and shape. The jawbreakers were good lysosomes

because they are the same relative size and shape. The Flat Jolly Ranchers are not good

representations of the Golgi apparatus because it is too thick and is not the same curvy shape.

The Sweet Tarts made good ribosomes because they are the same relative size and shape. The

Tupperware was a good vacuole because it was the same relative size and shape and it held out

the cytosol.

9. Explain why the following statement is true or not: All cells are bound by a solid cell

membrane.

It is not true because prokaryotic cell have only a cell wall and a cell membrane tends to act

more as a fluid than a solid.

10. In one to two paragraphs, explain what you got of the lab. Was it helpful or not? Explain.

This lab put the structure of a cell in a whole new perspective. Instead of thinking of each

component individually, I thought of the entity as a whole and not just a jumble of parts. The lab

was helpful because the candies attached a point of association with the organelles. The lab was

certainly a lot of fun and I know that everyone else enjoyed it.

1. Meiosis I and Meiosis II drawings

2. Meiosis I vs. Meiosis II Venn Diagram

3. Mitosis vs. Meiosis I Venn Diagram

4. Meiosis Simulation Lab

5. Take a Class Survey

6. Mendelian Genetics Activity

7. DNA Replication and Protein Synthesis

Take a Class Survey

I. Problem: Are certain traits controlled by dominant alleles more common than those controlled by

recessive alleles?

II. Hypothesis: I predict that the dominant traits will be more common.

III. Materials: Mirror (optional)

IV. Procedure

Observe each person in your class including the teacher and yourself for a widow's peak or

straight hairline, free or attached earlobes, a cleft or smooth chin, dimples, left or right thumb

clasping, the ability to roll the tongue, freckles, and right or left-handedness. Record your results

in a table.

V. Data

Dominant Trait Number of Students Recessive Trait Number of Students

Boys Girls Total Boys Girls Total

Widow's Peak 2 7 8 Straight Hairline 3 2 5

Free Earlobes 3 5 8 Attached Earlobes 2 4 6

Cleft Chin 1 1 2 Smooth Chin 5 7 12

Dimples 3 3 6 No Dimples 3 5 8

Left Thumb Clasping 3 4 7 Right Thumb Clasping 3 4 7

Can Roll Tongue 6 5 11 Can Not Roll Tongue 0 3 3

Freckles 3 6 9 No Freckles 2 3 5

Right-handed 4 9 13 Left-handed 1 0 1

VI. Analyze and Conclude

1. Did more students have dominant or recessive traits?

It varied by trait. Some people had more recessive than dominant such as having a smooth chin

and others had more dominant traits such as right-handedness.

2. What does this experiment suggest about the frequency of certain traits in a population?

It suggests that dominant traits occur more frequently than recessive traits in the class as a whole.

Other traits have a balance between dominant and recessive, such as the clasping of the thumb.

3. Conduct the same experiment with your family members. Are they similar to you?

See next page.

They were except for the fact that both parents had freckles but I did not.

Dominant trait Family Member Recessive trait Family Member

Mom

Dad

Tom

my

CJ

Jack

Andre

w

Mom

Dad

Tom

my

CJ

Jack

Andre

w

Widow's Peak Yes Yes Yes Yes Yes Yes Straight Hairline No No No No No Yes

Free Earlobes No Yes Yes Yes Yes Yes Attached Earlobes Yes No No No No No

Cleft Chin No No No No No No Smooth Chin Yes Yes Yes Yes Yes Yes

Dimples Yes Yes No No Yes Yes No Dimples No Yes Yes Yes No No

Left Thumb

Clasping

Yes No No No Yes No Right Thumb

Clasping

No Yes Yes Yes No Yes

Can Roll Tongue Yes Yes Yes Yes Yes No Can Not Roll

Tongue

No No No No No Yes

Freckles Yes Yes No Yes No No No Freckles No No Yes No Yes Yes

Right-handed Yes Yes Yes Yes Yes Yes Left-handed No No No No No No

1. Classification Lab

2. Animal Phylogenetic Tree

3. Animal Phyla Survey

4. Sponge Coloring

5. Cnidarian Coloring

Animal Phylum Survey

I. Purpose: To observe representative animals form various animal phyla

II. Materials: Preserved animal specimens

III. Procedure

Look at all twenty-four specimens. Record common name, phylum, whether it is a vertebrate or

invertebrate, characteristics, and observations.

IV. Data

Common Name Phylum Vertebrate or

Invertebrate

Characteristics Observations

Dragonfly Arthropoda Invertebrate Bilateral Symmetry

Exoskeleton

Made of Repeating

Segments

Large Eyes

Scaly Wings

Garden Spider Arthropoda Invertebrate Bilateral Symmetry

Exoskeleton

Open Circulatory

System

Eight Legs

Many Eyes

Portuguese Man O'

War

Cnidaria Invertebrate Bilateral Symmetry

Nerve Net

Stinging Tentacles

Pouch of Air

Balloon-Shaped

Head

Transparent

Jellyfish Cnidaria Invertebrate Radial Symmetry

No Skeleton

Nerve Net

Edges Have

Tentacles

Folds Visible

Transparent

Chicken Chordata Vertebrate Bilateral Symmetry

Cephalized

Backbone

Undeveloped

Feathers

Two Legs

Wings

Waterbug Arthropoda Invertebrate Bilateral Symmetry

Venomous

Made of Repeating

Segments

Forelegs Made For

Grasping

Brown Color

Leech Annalida Invertebrate Bilateral Symmetry

Tube-like Body

Segmented Body

Rusty Color

Visible Mouth

Sanguivorous

Lancelet Chordata Invertebrate Bilateral Symmetry

No Backbone

Repeating Segments

Gold Color

Transparent Fins

Crayfish Arthropoda Invertebrate Bilateral Symmetry

Fused Segments

Feelers

Fan-Shaped Tail

Gills

Mottled Brown

Color

Frog Chordata Vertebrate Bilateral Symmetry

Backbone

Closed Circulatory

System

Leopard Pattern

Muscular Legs

Webbed Feet

Starfish Echinodermata Invertebrate Radial Symmetry

Rough Skin

Central Mouth

Small Feet on

Bottom

Gray Color

Five Appendages

Sponge Porifera Invertebrate No Symmetry

Porous

No Tissues

Fuzzy

Brown Color

Pig Chordata Vertebrate Bilateral Symmetry

Heart

Closed Circulatory

System

Pink

Long Snout

Short Tail

Snail Mollusca Invertebrate Bilateral Symmetry

Shell

Eyes on Stalks

Wrinkled Skin

Spiral Shell

Turtle Chordata Vertebrate Bilateral Symmetry

Shell

Scales

Webbed Feet

Pattern on Shell

Tail

Honeybee Worker Arthropoda Invertebrate Bilateral Symmetry

Wings

Stinger

Fuzzy

Large Eyes

Antennae

Sand Dollar Echinodermata Invertebrate Radial Symmetry

Circular

Central Mouth

Slits

Fuzz on Body

Horsefly Arthropoda Invertebrate Bilateral Symmetry

Sanguivorous

Open Circulatory

System

Transparent Wings

Long Mouth

Six legs

Sea Anemone Cnidaria Invertebrate Radial Symmetry

Stinging Tentacles

Central Mouth

Black Bottom

Pink Color

Vase-Shaped, Long

Body

Roundworm Nematoda Invertebrate Bilateral Symmetry

Breathes Through its

Skin

Segmented

Long Body

Black Color

Painted Lady Arthropoda Invertebrate Bilateral Symmetry

Scaly Wings

Segmented Body

Colorful Wings

Slender Body

Mouse Chordata Vertebrate Bilateral Symmetry

Tail

Closed Circulatory

System

White Color

Furry

Whiskers

Earthworm Annelida Invertebrate Bilateral Symmetry

Segmented Body

Breathes through its

Skin

Long Body

Pinkish Color

Lubber

Grasshopper

Arthropoda Invertebrate Bilateral Symmetry

Exoskeleton

Open Circulatory

System

Long Legs

Antennae

Black and Orange

Color

V. Analyze and Conclude

1. Compare and contrast any two invertebrates.

See Separate Sheet.

2. Compare and contrast any two vertebrates.

See Separate Sheet.

3. Compare and contrast an invertebrate and a vertebrate.

See Separate Sheet.

1. Clam Dissection Lab

2. Earthworm Coloring

3. Earthworm Dissection Lab

4. Crayfish Coloring

5. Crayfish Dissection Lab

6. Starfish Coloring

7. Vertebrate Phylogenetic Tree

8. Reflection Essay

Tommy

Smith

Biology

Dr. Snyder

2/21/12

The Clam

Kingdom: Animalia

Phylum: Mollusca

Class: Bivalvia

Genus: Mya

Species: arenaria

II. Purpose: to examine the clam internally and externally by dissection

III. Materials

1. Dissection Tray

2. Clam

3. Scalpel

4. Ruler

5. Dissecting Needle

IV. Methods

A. External

The dissector first observed the incurrent and excurrent siphons at the posterior end of the clam.

They were black as though they had been burnt. The dissector measured the siphons and found

them to be 4 mm long and 5 mm wide. The dissector then observed the shell. There were two

shells held together by a thin gray ligament called the hinge ligament. The dissector then observed

the umbo of the shells on the dorsal side of the clam. The growth rings were then observed and felt

by the dissector before moving to the interior of the clam.

B. Internal

The dissector first slid the scalpel between the shells of the clam and cut the adductor muscles. He

then opened the shell and took the internal organs out of the shell. The dissector then used the

dissecting needle to cut through the remaining mantle. The dissector observed the large, peach-

colored gills. The gills are used to filter food out of the water and for gas exchange. The

dissector then located the visceral mass. The muscular foot was observed on the exterior of the

visceral mass. The muscular foot is used for locomotion. The dissector then turned the visceral

mass vertically and cut it using the scalpel. The dissector then observed the transparent intestines

and the green digestive glands. The dissector then observed the small, greenish heart and the

gonads. The gonads are reproductive organs. The dissector then broke the shell and observed

the three layers, the outer horny layer, the inner pearly layer, and the middle prismatic layer. The

dissector lastly cut the siphons vertically and observed the passages inside them. The dissector

failed to observe the palps and the stomach.

V. Observations

A. External

B. Internal

VI. Conclusion

1. Why are clams called bivalves?

The word “valve” refers to a shell and “bi” means two. Clams have two shells, so they are called

bivalves.

2. What is the function of the mantle?

The mantle covers all the organs in the mantle cavity. The mantle also secretes the

shell.

3. Describe the path of water through a clam.

The water first goes in through the incurrent siphon. Water then goes through the ostia or the

openings in the gills. Then the folds in the gills, the lamellae, lead the water into the cloacal

chamber and finally out through the excurrent siphon.

4. Describe the filter-feeding process of clams.

The food first goes in the through the excurrent siphon. Next it enters the gills where the food

becomes trapped in the mucus which coats the gills. The mucus is then taken to the palps which

separate the inedible inorganic particles are separated and the food is carried to the mouth. The

inedible particles are expelled out of the mantle edge. The food then goes to the stomach and is

digested by the digestive glands.

5. Identify and describe the role of digestive organs in a clam.

The digestive organs are responsible for breaking down food. The stomach, intestines, and the

digestive gland are digestive organs.

6. Describe how clams reproduce.

Eggs are held in the gills and sperm are held by the mucus lining the gills. The sperm then fertilize

the egg. Although some clams are hermaphroditic, meaning that they have both male and female

reproductive organs.

7. Describe the nervous system of a clam.

The clam have three pairs of connected ganglia. Ganglia are strands of nerve fibers that relay

impulses to the various organs. There is a pair of sense organs called statocysts which detect

changes in equilibrium. They are located behind the pedal ganglia.

8. Describe how clams use their foot to move.

The foot first extends from the shells. The end of the foot expands on the ground. The foot then

contracts, pulling the clam forward.

9. Describe the development of a freshwater clam.

The fertilized eggs first develop into a larva called a glochidium within the gills of the female. The

glochidium has two shells held together at the hinge by a ligament and a single adductor muscle.

The glochidium then latches onto a fish and is enveloped as the fish tissue grows. The glochidium

forms adult organs and exits the fish after ten to thirty days. The glochidium attaches itself to the

ground as a juvenile clam. This juvenile phase lasts until the clam in sexually mature in one to

eight years.

10. In one or two paragraphs, write about your dissection experience.

I thoroughly enjoyed the dissection experience. Slitting open the clam and having the juices run

down and out of the clam was like opening a cooked crab. It is messy, but you get a treasure on the

inside. It is also good to know about what you eat. Searching for the various organs was like

looking for things in a Search-And-Find book.

I saw the heart of the clam which I never would have thought would be green. I expected the

siphons to be more like tentacles. The intestines surprised me by being transparent in color. As a

start, this is one of the best you can have, and I hope that all the other dissections will be this

enjoyable.

Tommy

Smith

Biology

Dr. Snyder

3/16/12

The Earthworm

Kingdom: Animalia

Phylum: Annelida

Class: Oligochaeta

Genus: Lumbricus

Species: terrestris

II. Purpose: to examine the earthworm internally and externally by dissection

III. Materials

1. Dissection Tray

2. Earthworm

3. Scalpel

4. Dissecting Pins

5. Dissection Needle

6. Scissors

7. Forceps

IV. Methods

A. External

The dissector first felt the setae on the ventral side of the earthworm. The setae created a rough

texture although they were not visible to the naked eye. Next the dissector noted the gray dorsal

side and the lighter white ventral side. The dissector then counted the number of segments and

found them to be one hundred and forty-nine. The dissector next measured the length of the

earthworm which was 22 cm. The dissector noted the prostomium which is the upper lip of the

worm. He inserted a dissecting needle into the mouth so that it may be observed more easily. The

dissector pinned the earthworm down with a dissection pin at both the anterior and posterior ends.

He noted the clitellum, a small smooth area on the earthworm's body, and scraped the cuticle off the

body of the worm with the dissecting needle. The cuticle was transparent and had the appearance

of wax. The dissector lastly observed the sperm ducts located on the fifteenth segment. It was a

small gray line on the ventral side.

B. Internal

The dissector first grasped the skin below the clitellum on the dorsal side with the forceps and

stretched it upward. The dissector then made a small incision with a scalpel. Next the dissector

inserted the scissors into the incision and began to cut toward the anterior end. The dissector had to

cut the septa holding the skin the body with the dissecting needle and the scalpel. The dissector

pinned the skin to the dissecting tray with ten dissecting needles placed at an angle so as not to

obstruct the view of the interior. The dissector noted the intestine which was notched on the sides.

The dissector then observed the brain at the very anterior end of the worm. It was very small and

yellow. The dissector then noted the pharynx and the esophagus. The dissector next observed the

five aortic arches wrapped around the esophagus. They were small, thick, gray bands. The

dissector went down the worm to the crop. The crop was small, gray, and round; it was soft to the

touch. The dissector then observed the gizzard. It, like the crop was small and round, but it was

white and rigid to the touch. The dissector located the seminal receptacles which were small round

balls. The seminal vesicles, located at the side of the esophagus were more elongated versions of

seminal receptacles. The dissector observed the dorsal blood vessel on the dorsal side of the

intestine. The dissector lastly cut a cross-section of the worm and observed the typhlosol. The

dissector finally observed the smooth yellow muscle surrounding the intestine. The dissector failed

notice the ventral nerve chord and the nephridia.

V. Observations

A. External

B. Internal

VI. Conclusion

1. List the characteristics shared by all annelids.

All of the annelids are bilaterally symmetric, segmented, and coelomates.

2. What is the function of the setae?

Setae are used for locomotion.

3. What is another name for the segments of an earthworm?

The segments are also called metameres.

4. What is the function of the clitellum?

The clitellum secretes mucus for copulation, makes the cocoon in which the eggs are hatched.

5. How many hearts does an earthworm have? Describe them.

An earthworm has five aortic arches. They are like small gray bands wrapped around the

esophagus.

6. Describe the digestive process of an earthworm.

Food enters the body through the mouth. The food then goes through the pharynx to the esophagus.

The food then passes to the crop where it is stored temporarily. Next the food passes to the gizzard

where it ground by the sand within the gizzard. The food passes through the intestine where it is

stripped of all nutrients. The indigestible material exits the body through the anus.

7. What is the function of the typhosole?

The typhosole adds surface area to the intestine which makes digestion more efficient.

8. What is the term given for the slowing down of an earthworm's body?

The slowing down of an earthworm's body is called the diapause.

9. Distinguish between the different families of class Oligochaeta.

Family Aeolosomatidae are microscopic freshwater worms which reproduce asexually and feed on

algae. Family Tubificidae are red, freshwater worms which wave their anterior end in the water to

collect and then eat the floating material. Family Enchytraeidae are terrestrial and aquatic worms

which can be up to 25 mm long and are white in appearance.

10. In one to two paragraphs, describe your dissection experience.

I enjoyed my dissection experience. The worm had many more parts to it than the clam. I never

thought that hearts would look that and be gray. The dissection showed the complexity of even an

earthworm. The miniscule brain fascinated me to see something so small and so powerful. The

difficulty of opening up the skin without cutting something vital added to the excitement. This

dissection was a memorable experience and I look forward to the next dissection.

Tommy

Smith

Biology

Dr. Snyder

3/30/12

The Crayfish

Kingdom: Animalia

Phylum: Arthropoda

Subphylum: Crustacea

Order: Decapoda

Genus: Cambarus

Species: sp.

I. Purpose: To examine the crayfish internally and externally by dissection.

II. Materials

1. Dissecting tray

2. Crayfish

3. Scalpel

4. Scissors

5. Dissecting Probe

6. Forceps

IV. Methods

A. External

The dissector first observed the first swimmerets which indicated that the specimen was a

female. The dissector then measured the antennae which were ten centimeters long. He next

measured the body which was ten centimeters long. The antennules were eight tenths of a

centimeter long. The dissector next measured the claws which were 4 centimeters long. The

dissector next observed the bumpy carapace and the rostrum. The protuberant, compound eyes

attracted the attention of the dissector next. The dissector next observed the cephalothorax

which includes the head and the thorax, and the abdomen, which consists of seven segments and

the telson; both are a crimson color. The dissector observed four pairs of walking legs and five

pairs of swimmerets. The dissector noticed a small protuberance at the joints of the second

walking legs. Then, going down the body, the dissector observed the small fan at the end of the

tail which is composed of the uropods and the telson. On the ventral side, the ventral blood

vessel was observed. The dissector observed the anus before moving to the mouth. The

dissector first removed the third maxillipeds which were large and bristled. The dissector the

removed the second maxillipeds, underneath the first, which were similar to the third

maxillipeds but smaller. The dissector then removed the first maxillipeds which were small and

similar to tentacles. The dissector removed the thin maxillae which covered the mandibles. The

dissector lastly pulled out the tooth-like mandibles before finding the mouth and moving on into

the internal anatomy.

B. Internal

The dissector first made two parallel cuts with the scissors on the dorsal side of the crayfish from

the telson to the head. The dissector carefully removed the exoskeleton and observed first the

intestine which had been dyed pink and the tail muscles. The dissector next removed the head

and observed the bladder and green glands within the head. After removing the latex inserted

into the crayfish, the dissector observed the pink dorsal heart and the pastel yellow stomach on

the dorsal side of the crayfish. The dissector noticed the transparent miniscule circumesophageal

nerve. The dissector lastly observed the feather-like gills. The dissector did not observe the

gonads or the brain.

V. Observations

A. External

B. Internal

VI. Conclusion

1. Identify at least four animals that belong to subphylum Crustacea.

Crabs, shrimp, lobsters and crayfish belong to subphylum Crustacea.

2. Identify at least three distinguishing characteristics of subphylum Crustacea.

They have a chitinous exoskeleton, gills, two pairs of antennae, a pair of maxillae and

mandibles.

3. What characteristics do annelids share with arthropods?

They both are segmented. They have an anterior, dorsal brain

4. What distinguishing characteristics do crustaceans have from annelids?

Crustaceans have an exoskeleton, an open circulatory system, a complex muscular structure, a

distinct heart.

5. Identify and describe the function of all mouthparts found in a crayfish.

The mandibles chew food. The maxillipeds handle food and function as touch receptors. The

maxillae also handle food and draw water over the gills.

6. Identify the main arteries found in a crayfish. What organs are supplied by these arteries?

The opthalmic artery supplies the head and the esophagus. The antennary arteries supply the

stomach, the green glands, the antennae and the lateral portions of the head. The dorsal

abdominal artery supplies the intestine and the tail muscles. The hepatic artery supplies the

heptopancreas. The sternal artery branches into the ventral thoracic and the ventral

abdominal muscle. The ventral thoracic supplies the leg muscles. The ventral abdominal artery

supplies the tail muscles.

7. Identify the habits of a crayfish.

Crayfish are crepuscular. They are active at sunrise and sunset when they come ashore looking

for food.

8. Identify the four genera of crayfish.

The four genera are Cambarus, Procambus, Oroconectes, and Astacus.

9. What do crayfish eat?

Crayfish eat snails, tadpoles, insects, terrestrial plants, and aquatic plants.

10. In one to two paragraphs describe your dissection experience.

I enjoyed dissecting an animal as complex as the crayfish. The mere number of all the parts on

the exterior made it a great puzzle. I never would have believed that a crayfish had so many

mouthparts. My only dislike was the latex on the interior which made me accidentally tear out

some of the heart. Other than that I enjoyed every minute of the dissection of the crayfish.

Tommy Smith

Biology

Dr. Snyder

4/23/12

The Starfish

Kingdom: Animalia

Phylum: Echinodermata

Class: Asteriodea

Genus: Asterias

Species: sp.

I. Purpose: To examine the starfish internally and externally by dissection.

II. Materials

1. Dissection tray

2. Starfish

3. Scissors

4. Microscope

5. Dissecting Needle

IV. Methods

A. External

The dissector first observed the five arms radiating from a central disc. The dissector next

measured the arm length and found it to be five centimeters long. The dissector then felt the spines

which cover the starfish's body. Despite the name, they were not sharp and created the texture of

sandpaper. The dissector then observed the madreporite on the aboral surface. The madreporite

was like a small, round pebble set in the skin of the starfish. The starfish had a large, almost

gaping

mouth in the center of the oral surface. At the tip of each arm was a small, hard, white eye-spot.

The dissector then observed the ambulacral groove and the two lines of tube-feet on each side. The

tube-feet were small, fleshy, tan-colored protuberances. At the base of each tube foot was a

swollen sac called an ampulla. The dissector lastly noticed a tiny hole in the center of the aboral

surface of the starfish which was the anus.

B. Internal

The dissector first cut off the tip of the arm which was furthest from the madreporite. The

dissector then made a shallow cut around the edge of the arm and around the central disc. The

dissector removed the skin and observed the endoskeleton on the underside. The endoskeleton was

fascinating; it was like a net or a spiderweb on the skin. The dissector next observed a wrinkled,

yellow-green sheet of tissue called the digestive glands. After removing the digestive glands, the

dissector observed the radial canal. The radial canal was white and segmented; its appearance was

not unlike that of a backbone. On the sides of the radial canal were transparent jelly-like structures

called the gonads. The dissector scraped some of the gonads from the starfish and placed it under a

microscope to determine its gender. The dissector was unable to conclude its gender with absolute

certainty, but the dissector believes it was a female. The dissector next observed a thin

slip of tissue which was the pyloric stomach. The dissector next observed the cardiac stomach,

which consists of small green pouches around the mouth. The dissector next observed the stone

canal, a small white vein of tissue going from the madreporite. The dissector lastly observed the

ring canal, which was similar to the radial canal in appearance; it just formed a circle around the

mouth.

V. Observations

A. External

B. Internal

VI. Conclusion

1. In what ways are starfish unique to the other invertebrates you have studied so far?

They are deuterosomes, they have an endoskeleton, and they have a water-vascular system.

2. What are the main differences between deuterosomes and protosomes?

Protosomes are determinate, the archenteron forms the mouth, and have complete segmentation.

Deuterosomes are indeterminate, the archenteron forms the mouth and have incomplete

segmentation.

3. Where do echinoderms live?

All echinoderms live in aquatic enviroments.

4. Identify five classes of echinoderms. Give an example of each.

The class crinoidea includes feather stars. The class ophiuroidea includes both basket stars and

brittle stars. Class asteroidea includes sea stars. Class echinoidea includes sea urchins and sand

dollars. Class holothuriodea includes sea cucumbers.

5. How many species of starfish are there?

There are 1700 species of starfish.

6. Identify at least four external features of a starfish. What is their function?

They have pedicellariae, which are tiny pincers which remove sediment and keep other organism

from growing on them, a madreporite, which allows water to enter the water-vascular system, and

skin gills, which allow the starfish to breathe.

7. Describe the process of water movement through the water-vascular system.

Water enters the madreporite. Then it goes to the stone canal and the ring canal. The water then

goes to the radial canal. From the radial canal it goes to the ampullae and tube feet.

8. Identify the parts of and describe the digestive process of the starfish.

The digestive system is composed of the pyloric stomach, the cardiac stomach, the mouth and the

digestive glands. It starts when a starfish uses its tube feet to pry open a bivalve. The starfish

then extends its cardiac stomach and partially digests the bivalve. The cardiac stomach then

retracts and the food enters the mouth where the cardiac stomach transfers it to the pyloric

stomach.

9. Describe the skeleton of a starfish.

A starfish has an endoskeleton made of calcium carbonate plates called ossicles.

10. In one to two paragraphs, describe your dissection experience.

This dissection was the easiest that we have done. There was more to see than in the clam, but

that was better. I enjoyed looking in the microscope at the gonads. Because it was such an easy

dissection, I had the opportunity to look around more. I saw all of the parts in greater detail and

was able to get more out of the dissection.

Class Characteristics

Agnatha: Fish with elongated bodies, lack of paired fins, bone and jaws. Includes hagfish and

lampreys.

Chondrichthyes: Cartilaginous fish with jaws and paired fins. Covered in a unique type of scale called

a placoid scale.

Osteichthyes: skeleton made of bone; two main groups, bony-finned fishes and lobed-finned fishes;

more than 23,000

Amphibia: skin thin and permeable to gases; lay eggs in water and pass through aquatic larval stage

Reptilia: dry, scaly skin; eggs protect embryo from drying out; eggs can be laid on land; about 6,000

species

Aves: characterized by characteristics which enable flight, these includes feather, hollow bones and a

unique respiratory system; over 10,000 species

Mammalia: all have hair and nurse their young with milk; about 4,400 species

1. What characteristics are common to all vertebrates?

All vertebrates have a vertebral column, a cranium, and an endoskeleton made of bone or cartilage.

2. What key characteristic separates the classes Chondrichtyes and Osteichyes?

Members of class Chondrichthys have a cartilaginous skeleton. Members of class Osteichthyes have a

skeleton made of bone.

3. What adaptations lead to the divergence of mammals?

Mammals have fur or hair and nurse their young with milk.

4. What two groups of vertebrates carry the most recent common ancestor?

Classes Reptilia and Aves have the most recent common ancestor.

Reflection Essay

This year in science was centered on the study of life, biology. The course of the year started

from smallest to largest. In biological terms this would mean from microscopic cells to the actual

organisms.

In the first quarter, we began with ways to observe life which included the scientific method and

microscope. These of course led to the cell. Even more basic than the cell is the organisms within

them. Organelles are tiny “organs” within the cell that resemble the human body. When you start with

one cell, you will probably end up with two. Thus the process of mitosis came into our studies and we

ended the quarter with that.

When you start with two organisms, you will probably end up with three. When we began the

study of mitosis, we learned about how we came into being. Mitosis I, II and mitosis were a cause for

ambiguity which was quickly cleared out. Then I had a fun time observing my classmates for dominant

and recessive traits. Dominant traits are genetic patterns of DNA which trump the recessive traits. As a

final bonus, we studied the process of DNA replication and protein synthesis, which is how proteins are

made.

After studying the components, the organisms were next in Quarter Three. First Linnaeus and

his famous system of classification was studied. Then after a brief look at evolution, we headed off to

the individual phyla. First was Phylum Porifera, which consisted of sponges. They are not the most

interesting creatures, but they are indeed the simplest. Then came the Cnidarians, which consisted of

jellyfish, sea anemones, and coral. They are much more complex than a sponge. The first nervous

system and symmetry show themselves here. The deadly cnidocytes are what gives a jellyfish its toxic

interest.

This quarter began the dissections. First came the clam. The hardest part of the dissection was

to get the clam open, but it was still rather simple. Here, though, the circulatory system shows itself.

Then the earthworm was taken apart. Here is the first complex muscle structure and centralized

nervous system, which includes a brain. Next was the ever-so complex crayfish. Here is a higher

degree of cephalization and an exoskeleton. Muscles designed for complex coordinated movements

were developed by arthropods. They did however make the regression of an open circulatory system.

Last before portfolio was due is the starfish. There was very little to to look at. It was fun to look at

the gonads under the microscope. Starfish made the progression of deuterosome development and an

endoskeleton. They made the regression of no cephalization and no circulatory system. The

dissections were my favorite part of the year.

This year was spent in my favorite area of science, biology. The insides of various creatures

was fun to look at. I felt it is good to know what makes up me. I look forward to chemistry next year

and to working in your class again.