Cnidaria
Do some Cnidarians switch between polyp and medusa body plans or do they stay the same their whole lives?
Many cnidarians switch between polyp and medusa. This is called alternation of generations.
How does the sponge get nutrients?
Filter Feeding
Large opening at the top of a sponge that water and waste exit
through
Osculum
Explain how sponges obtain oxygen. (Explain- not just one word)
Sponges don't have any respiratory organs. Instead, they have oxygen diffuse from an area of higher concentration in the water across their cells to an area of lower concentration inside the sponge.
We have confirmed fossil records of cnidarians from up to…
580 Million Years ago
What is the highest level of internal organization that cnidarians have?
Tissue
Daily Double!
Are cnidarians diploblastic or triploblastic?
Are they Protosomes or deuterostomes?
What type of symmetry do they have?
They are diploblastic, neither protostomes nor deuterostomes, with asymmetry
What is the job of the excretory system of an animal?
To get rid of waste
Explain the difference between internal budding and external budding in sponges AND what type of reproduction it is.
External budding in the more standard type of asexual reproduction seen in most sponges. When it is internal it is because there are unfavorable conditions that threaten the sponges life. It will form a gemmule inside the spongocoel that lies dormant and allows it to survive until conditions become favorable again.
Medusa or polyp?
umbrella-like, free-swimming, with the mouth facing down
Medusa
Where would you not find a living cnidarian?
Land
What is the proper pathway of water through the body plan of a simple sponge?
Ostia to spongocoel to osculum
What is the purpose of a cnidocyte?
Cnidocytes are used to capture and immobilize prey by stopping its heart and nervous system
Explain sexual reproduction in sponges (hint: use the 6 steps in your own words)
The “male” sponge produces sperm and releases it out the osculum. The sperm then enters the ostia of a “female” sponge where the choanocytes trap it. The sperm is transferred to the mesohyl where it fertilizes the egg cell. The zygote will develop into a larva and be released out to the water. The larva will swim around until it finds a spot to develop into an adult sponge.
How would you describe the digestive system of cnidarians?
They have an incomplete digestive system because they have only a mouth and a
gastrovascular cavity
How many species of cnidarians have been discovered so far?
14,515
How many species of sponges have been discovered so far?
8,550
Which cell is responsible for the digestion of food in a sponge?
Choanocyte
How does the phylum name “Cnidaria” fit and describe the animals included within this phylum?
Cnidaria means stinging, every Cnidarian has a cnidocyte that acts as its "stinger"
A group of sponges living together is known as a
Colony
Are cnidarians diploblastic or triploblastic?
Are they Protosomes or deuterostomes?
What type of symmetry do they have?
They are diploblastic, neither protostomes nor deuterostomes, with radial symmetry
We have confirmed fossil records of sponges from up to…
500 million years ago
Area inside of a cnidarian that is lined by the endoderm and digests
food, circulates nutrients, and diffuses gasses
Gastrovascular Cavity
Outline the process of filter feeding in sponges. (vocab terms to use: ostia, osculum, choanocytes, amoebocytes, spongocoel, and mesohyl)
Choanocytes will create a current that pulls water and food particles into the ostia. It will also trap the food particles and digest it. The nutrients will be transferred to the amoebocytes to be delivered throughout the body through the mesohyl. After water is filtered it enters into the spongocoel and exits out of the osculum.
How would you describe the simple sponge body plan?
An outer and inner layer of cells separated by mesohyl