How many layers of cells are found in sponges?
2 layers!
What is the name of the stinging cells found in all Cnidarians?
Cnidocytes
(Nematocyts are a structure within the Cnidocyte)
Which class of echinoderm is the largest? (Has the greatest numberof species)
Name an animal in this class.
Ophiuroidea- Brittle Stars and Basket Stars
The eggs of creatures in class Chondrichthyes are called this.
Mermaid Purses
Coelacanths are examples of...
Lobed Finned Fish or Sarcopterygii
What is the name of the jelly substance found between layers of sponge cells?
Mesohyl
In the Phylum Ctenophra, comb jellies do not have cnidocytes. Instead they have... which function by...
...Coloblasts which function by secreting a sticky substances that binds prey to the ctenophore.
Aristotle's Lantern is a structure found in sea urchins, what does it do?
Allows the sea urchin to bite/scrape and consume its prey.
In reproduction, skates are _ while rays are _.
Skate are oviparous
Rays are ovoviviparous
Name the different classes of fish. (Hint: there are 5)
Myxini
Cephalaspidomorphi
Chondrichthyes
Sarcopterygii
Actinopterygii
Why are sponges important to earth's ecosystems?
Sea sponges provide habitat structures that attract/protect other species. They also filter naturally occurring and pollutant chemicals out of ocean water which keeps water quality suitable for life.
Name the classes of Cnidarians. Provide an example of an animal in each.
Scyphoza- Jellyfish
Cuboza- Box Jellies
Hydroza- Hydra, Portuguese Man-o-War
Anthozoa- Sea Anemone, Coral
Name the 3 classes of Echinoderms and an animal that belongs to each class.
Asteroidea: Sea stars
Ophiuroidea: Brittle stars and Basket Stars
Crinoidea: Sea lilies and feather stars
Echinoidea: Sea urchins and sand dollars
Holothuroidea: Sea cucumbers
What is the function of swim bladder?
Use gas to increase or decrease a fish's buoyancy in water. This helps the fish as it does not need to work as hard to maintain its position in the water (working against sinking or floating forces).
If a cell is surrounded by a solution that is less salty than the inside of the cell what direction does water flow across the cell membrane? What happens to the cell?
If a cell is surrounded by a solution that is more salty than the inside of the cell what direction does water flow across the cell membrane? What happens to the cell?
If a cell is surrounded by a solution that is less salty than the inside of the cell water flows INTO the cell. The cell becomes larger, plumper, and could burst.
If a cell is surrounded by a solution that is more salty than the inside of the cell water flows OUT of the cell. The cell becomes smaller and may begin to shrivel up.
What is a gemmule? Why are they important?
Gemmules are balls of sponge cells that can survive harsh conditions and later reproduce the original sponge asexually. They are important to sponge survival through harsh conditions.
What phylum and class do Hydra belong to? Draw a diagram of a hydra with a bud including a “zoomed in” view of a cnidocyte (with arrow of where to find on hydra).
Your answer must include the words: Tentacle, mouth, gastrovascular cavity, basal disk, bud, cnidocyte, pneumatocyst.
Hydra belong to phylum Cnidara, class Hydrozoa.
+ Accurate drawing (See lecture slides for Hydra and Cnidocyte figures)
Describe how starfish consume their prey.
Use the words Cardiac Stomach, tube feet, Pyloric stomach, and Digestive glands in your answer.
Starfish begin to consume their prey by moving their prey towards their mouths using their tube feet. The starfish then extends its Cardiac Stomach out of its mouth and wraps it around its prey. The consumed prey then travels to the Pyloric stomach and is then dispersed to the digestive glands in each arm where nutrients are digested for use by the starfish.
Discuss 2 adaptations found in Chondrichthyes that are not found in Cephalaspidomorphi or Myxini. What advantages do these adaptations provide?
Moveable Jaws- improved predation/hunting
Paired Fins- greater control of movement, less work to move
Placoid Scales- decreased turbulence of water flow over skin, more fluid dynamic.
What is buccal pumping and how does it help fish?
Buccal pumping is when fish "swallow" water or take water in through their mouths and run it over their gills. This action increases the amount of water and oxygen the gills are exposed without requiring the fish to swim and create a current of water over the gills.
Explain how Porifera feed and take in nutrients.
Your answer must include the words: Ostia, Osculum, Choanocytes, Amebocytes, and Mesohyl.
Choanocytes line the inner layer of the sponge and move their flagella to create a current that draws water into the sponge through ostia which are pores for water flow located on the outside layer. As water flows through the sponge, so do small bits of food. Choanocytes engulf these bits of food when they come in contact with them. The choanocyte then passes the food to an Amebocyte which then travels through the mesohyl, a jelly-like layer of the sponge, and carries the food to an area of the sponge in need of nutrients. Water exits the sponge through the osculum (opening at the top of the sponge).
Explain the lifecycle of a Jellyfish from fertilized egg to adult medusa. In your explanation, be sure to include a description of what strobilation is and if it is a process of sexual or asexual reproduction.
Jellyfish begin their lives as a fertilized egg. This egg then develops into a free swimming larva which later attaches itself to a substrate as it matures. Once attached to a substrate, the larva develops into a polyp. The polyp then undergoes the process of strobilation where it creates genetic clones (asexual reproduction) of itself that nest together until developing large enough to detach and live as a juvenile jellyfish in medusa form. As the juvenile medusa grows it will eventually become an adult medusa when it can reproduce sexually by producing eggs and sperm.
Describe the flow of water and name the parts of the water vascular system in starfish, then describe what does the water vascular system allows the starfish to do.
Water enters the starfish’s water vascular system through the Madreporite. The madreporite helps filter out any particles that may be in the water. After the madreporite, the water travels through the stone canal for more filtration before entering the ring canal. Once in the ring canal, water travels to the radial canal and then finally to the tube feet.
Starfish use the water vascular system to create water pressure that, along with muscles in the tube feet, allow the starfish to move the tube feet and create suction. This movement and suction allow the starfish to move and hold on to surfaces, and carry food to their mouths.
Name and explain the 3 different ways that shark females can reproduce/have their young. What are advantages and disadvantages to each?
Draw and explain the flow of blood through a fish heart and body.
Your answer should include the words Sinus Venosus, Bulbus Artiosus, Atrium and Ventricle. Your answer should also include where blood is oxygenated vs. deoxygenated.
Deoxygenated blood enters the fish heart and is pumped from the Sinus Venosus to the Atrium, then from the Atrium to the Ventricle, then from the Ventricle to the Bulbus Arteriosus. Blood leaves the heart deoxygenated and the travels to the capillaries that cover the gills. While in the gill capillaries the blood becomes oxygenated. The blood then travels to where oxygen and nutrients are needed in the fish’s body and once again becomes deoxygenated. The deoxygenated blood then flows back to the heart where it is pumped to the gills once again.