worms, cnidarians, and sponges review sheet answers
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Worms, Cnidarians,and SpongesReview Sheet Answers
Sponges #1
What is an invertebrate?Invertebrates are animals that do not have backbones.
Sponges #2
What does asymmetrical mean?
It has no symmetry.
Sponges #3
Define sessile.An organism spends its life attached to one spot and does not move from place to place.
Sponges #4
What are pores? How do they help sponges?
Small openings that surround the entire body of a sponge. They allow water and oxygen to enter the sponge’s body.
Sponges #5
How do sponges obtain food and oxygen?
Water travels through the pores and it carries food and contains oxygen molecules. The specialized cells filter them out.
Sponges #6
Do sponges have tissues, cells, or organs?
CELLS!!
Sponges #7
What are spikes? How do they help sponges?
They form a rigid frame that helps support the sponge’s body. They also are a defense mechanism.
Sponges #8
Describe the two types of reproduction.
Asexually: Budding. Buds form on the parent sponge and eventually break off and float away.Sexually: Fertilization. Sperm are released by a male sponge and then fertilize a female’s eggs.
Sponges #9
What is a larva?A fertilized egg becomes a larva. It is the immature form of the adult and looks very different.
Cnidarians #10
What is radial symmetry?
Many lines of symmetry, all through a center point.
Cnidarians #11
How are cnidarians’ tentacles unique?
They have stinging cells.
Cnidarians #12
What is a nematocyst?A capsule in the stinging cell that holds a barbed filament.
Cnidarians #13
Cnidarians are more advanced than sponges because they have….
TISSUES!
Cnidarians # 14
Describe the two types of reproduction of cnidarians.
Asexual – Budding (buds form on the adult, break off, float away, and then attach to the ocean floor).Sexual – Sperm are carried to the egg where fertilization occurs.
Cnidarians # 15
What is a polyp?Vase-like shape.
Mouth is on the top.
Sessile
What is a medusa?Free swimming animal.
Mouth is on the bottom.
Looks like an upside down bowl.
Worms #1
What are the 3 types of worms?
Flatworms: they are FLATRoundworms: they are ROUNDSegmented worms: they have SEGMENTS
Worms #2
What is bilateral symmetry?
Only one line of symmetry in the animal.
Worms #3
What is regeneration?The ability to regrow body parts.
Worms #4
What is a parasite?Organism that lives on or in another organism.
Worms #5
What is an eyespot?Allow the organism to see light versus dark. Planaria have them.
Worms #6
What are odor cells?Allows the organism to smell food. Planaria have them.
Worms #7
How do planaria eat?They insert feeding tubes into the food.Next, digestive juices start to digest the food outside the worm.Finally, the feeding tubes bring the prey into the worm.
Worms #8
Where do most roundworms live?
Moist environments
Worms #9
What type of digestive tract do roundworms have?
Open at both ends or one way.
Worms #10
• What are segments?– Tiny linked sections that
cover the worm’s body.
Worms #11
• Describe the digestive tract of segmented worms.– Open @ both ends –
One Way.
Worms #12• Describe a closed circulatory
system. What is it and why do some animals have it?
•Blood moves through a connected network of blood vessels.
• It is important because it allows animals to grow larger.
Worms #13
• What does it mean that earthworms are scavengers?– They eat decayed plant
and animal remains in soil.
Worms #14
• Why do earthworms need moisture?– They get oxygen from the
water that’s on their skin. – No moisture = no oxygen.
Worms #15
• How do earthworms help gardeners and farmers?– Tunnels loosen soil and
provide room for air, water, and roots, which promote plant growth.