Chapter 23 & 24 Flashcards
Where does the name cnidarian mean? Give three characteristics of this group.
Cnidarian means stinging nettle plant.
- radially symmetric
- two layered body
- Medusae and polyp life style
How do Cnidarians obtain their food?
Their stinging cells help to capture prey.
Jellyfish lack circulatory, excretory, and support structures. Why are these organs not necessary? What limitation does this place on their habitat?
Each cell is in contact with the water and can diffuse material directly in and out of the cell. They are restricted to a water habitat.
Most Cnidarians alternate between a Medusa and polyp stage. What is a disadvantage and an advantage of the polyp stage? How does this compare to sponge life cycle?
Polyp Disadvantage- can not disperse, can not move to find food or escape an unfavorable environment.
Advantage- does not expend energy on moving.
Both sponges and jelly fish have a sessile and mobile stage.
The polyp reproduces asexually and the Medusa reproduces sexually. What are the advantages and disadvantages sexual and asexual reproduction?
Sexual reproduction is not as efficient as asexual reproduction. Sexual reproduction adds and maintains variability in a species and increases the chance of survival of some offspring in a changing environment.
Both sponges (Porifera) and Cnidarians lack of Brian. What is the disadvantage of lacking a brain?
There will be no memory, learning, decisions, etc.
What can we say about the habitat of Cnidarians?
Cnidarians are restricted to water and are largely dependent upon water currents.
Give four adaptations that the has tapeworms for a parasite life?
Multiple hosts, sexual and asexual reproduction, a scolex with hooks, lack a gastrovascular system
Describe the life cycle of a the beef tapeworm
Cow, cyst in muscle, humans eat the muscle, human’s intestine, egg, cow eats egg
Describe the life cycle of the pig tapeworm.
Tapeworm lives in the human intestine, egg, pig eats egg, tapeworm forms a cyst in the pig muscle, humans eat the pig muscle.
How do humans acquire the pig tapeworms and what can be done to prevent infection?
Eating the pig muscle. It can be avoided by thoroughly cooking the muscle.
How do pigs acquire the tape worm and how can that be avoided?
Pig infection can be avoided by the proper treatment of human waste.
Give four functions of the mantle in a mollusk
Respiratory chamber, in bivalves it aids in feeding, in some mollusks it serves as a brood chamber, and can aid in locomotion
How does a shell extend the habitat of a snail?
Provides protection and prevents water loss
A clam shell limits the ability of a clam to find a mate and disperse. How are these problems solved? What is a trochophore larvae?
Gametes are released into the water allowing for dispersion and the trochophore larvae is free swimming.
The characteristics of echinoderms are interlocking what symmetry as an adult.
Spines, radial
What do starfish eat and how do they eat?
They eat bivalve mollusks by forcing its stick into the bivalve shell and externally digesting the clam.
Speculate what would happen if starfish were eliminated from an ecosystem.
The clams would become too numerous and reduce their food source.
Starfish are called a keystone species. What is a keystone species and why are starfish called a keystone species?
A keystone species is a species which critical for the preservation of the ecosystem. If starfish are removed the clams will over populate.
Speculate what would happen if all mosquitoes were eliminated?
Mosquitoes are a food source for many animals, and they are important pollinators. Without mosquitoes the ecosystem would probably continue; however, there would be a relative change in species composition.
Speculate on why moths are attracted to light. Do artificial lights cause a problem for moths? explain.
Moths use a light source for navigation. Artificial lights may cause a decline in moths numbers by interfering with finding a mate.
Pine bark beetle kills a species of pine trees. Is this all bad? Explain.
Pine bark beetles eliminate pine trees; however, the elimination of pine makes room for other species.
Phylum Chordates derives its name from
Notochord.
The function(s) of the notochord are (is)
All of the above
The notochord becomes part of the vertebrae in vertebrates.
True
All chordates have vertebrae.
False
All amniote eggs have a hard shell.
False
The amniote is named after the amnion sac.
True
The amniotic sac is part of the mother’s circulatory system and supplies nutrients to the embryo.
False
The advantage of the cartilage skeleton of a shark is that it is lighter than a bony skeleton and, consequently, swimming takes less energy.
True
Salamanders must live around water because of their life cycle.
True
Salamander are amphibians
True
Most amphibians can absorb oxygen through their skin, which is why the skin must remain moist.
True
Lizards are amphibians
False
Salamanders do not undergo metamorphosis.
False
Frogs must remain around water because of their life cycle.
True
A turtle is a reptile.
True
Scales and a hard egg covering allow reptiles to live in dry habitats.
True
Incubation temperature of alligator eggs determines the embryos gender.
True
A four chambered heart allows better oxygenation by preventing the mixing of oxygenated blood and non oxygenated blood.
True
All reptiles have a four chambered heart.
False
Amphibians need a four chambered heart.
False
Bird feathers help in flight, insulation, and courtship displays.
True
Birds are ectothermic.
False
The various type of teeth allow mammals a wider selection of food.
True
The characteristics of mammals include hair and mammary glands.
True
Birds have hair.
False
One advantage to a marsupial is that the mother gives birth to a smaller baby, which is less risky for the mother.
True
Marsupials only live in Australia
False
The human placenta helps to feed the embryo.
True
The placenta prevents the mixing of the embryos and mothers’ blood, thus preventing the mother from rejecting the embryo as a forge in object.
True
