Biology Exam 2

Question 1

Define polyphyletic

Answer 1

could have multiple different answers, ex. aschelminthes

Question 2

define pseudocoelome

Answer 2

false body cavity, lacks peritoneal linings and membranes, often fluid-filled

Question 3

define hydrostatic skeleton

Answer 3

fluid, mostly water, exerts pressure, which gives support and shape

Question 4

What are some characteristics of Aschelminthes?

Answer 4

phylum of pseudocoelmates with hydrostatic skeletons, cuticle, pharynx, complete digestion, mostly dioecious, microscopic, protoniphridia, no circulatory system, primitive brain, no real eyes, and eutely

Question 5

What is a cuticle?

Answer 5

a thin, protective layer that covers the body

Question 6

dioecious definition

Answer 6

separate sexes

Question 7

define eutely

Answer 7

number of cells constant for each organ and the entire animal in all individuals of a given species

Question 8

Summarize Rotifera

Answer 8

2000 species, Phylum Rotifera, freshwater, corona for feeding, master to grind food, foot with 2 toes, parthenogenetic

Question 9

define parthogenesis

Answer 9

all female reproduction

Question 10

Summarize Spiny-headed worms

Answer 10

Phylum Acanthocephala, 1000 species, endoparasites, retractable proboscis, no digestive system, arthropod host then fish

Question 11

Name the 5 ecdysozoans

Answer 11

Nematoda, Nematomorpha, Anthropoda, Onychophora, Tardigrada

Question 12

Summarize Roundworms

Answer 12

Phylum Nematoda, 1600 species, parasitic or free-living, cuticle is molted 4 times, chemoreceptors, complete digestive, osmoregulate, dioecious

Question 13

define osmoregulation for nematodes

Answer 13

free-living nematodes have ventral glands, renettes, that absorb wastes from pseudocoelom, whereas parasitic ones have a tubular system with long canals and an excretory pore.

Question 14

Giant Intestinal Roundworm

Answer 14

Nematodes, single host, lives in small intestine

Question 15

Pinworm

Answer 15

Nematoda, single host, large intestine, eggs hatch and molt in small intestine

Question 16

Horsehair Worms

Answer 16

Nematomorpha, 250 species, very long, skinny worm, in running or standing water, free-living adults, larvae parasitize arthropods

Question 17

Summarize Phylum Mollusca

Answer 17

100,000 species, protostomes, lophotrochozoans, coelom,, 3-part body, head-foot, visceral mass, and mantle, noticeable head, radula, digestive system, open circulatory system, mantle cavity, dioecious

Question 18

What are the functions of the coelem

Answer 18

room for organ development, diffusion surface for gases, nutrients, and wastes, storage, elimination of reproductive product, hydrostatic support

Question 19

What is contained in the visceral mass of mollusks?

Answer 19

digestive, circulatory, reproductive, and excretory organs

Question 20

Mantle cavity functions

Answer 20

excretion, gas exchange, elimination of wastes, release of reproductive product

Question 21

define radula`

Answer 21

tongue-like rasping structure

Question 22

Summarize Snails and Slugs`

Answer 22

Phylum Mollusca, Class Gastropoda, gastro meaning stomach soda meaning foot, 350,000 species, largest class, some venomous, torsion, breathe through single gill in mantle cavity, hydraulic skeleton, open circulatory system, mucous gland, real eyes, dioecious

Question 23

Define torsion

Answer 23

180 degree twist of visceral mass, mantle, and mantle cavity that positions gills, anus, reproduction, and excretory openings behind the head

Question 24

Summarize Clams, ysters, Mussels, Scallops

Answer 24

Phylum Mollusca, Class Bivalvia, bi meaning 2, valve meaning valves, 2nd largest class, 300,000 species, laterally compressed, no head or radula, wedge-shaped foot, gills, filter feeding, open circulatory, dioecious, marine and freshwater

Question 25

Summarize Octopi, Squid, and Nautilus

Answer 25

Phylum Mollusca, Class Cephalopoda, may have shell, 550 species, marine, largest invertebrates, complex eyes, anterior foot, mantle cavity with jet propulsion, release ink, beak-like jaws and a radula, some venomous, closed circulation, complex nervous system, dioecious, special tentacle for reproduction

Question 26

List classes under Annelida

Answer 26

Polychaeta, Clitellata, Hirudinea

Question 27

Define Metamerism

Answer 27

diversion of body into serially repeated sections along anterior/posterior axis

Question 28

Describe the digestive system of annelida

Answer 28

complete digestive system forming straight tube through the body

Question 29

Define tagmatization

Answer 29

modification of body regions for specialized functions

Question 30

Summarize Class Polychaeta

Answer 30

Tubeworms, Clamworms, and Fanworms, 5300 species, marine, live in shells, rocks, or burrows, move with setae and parapodia, undulating, or swimming, greater cephalization, have prostomium, eyes can be simple receptors or complex eyes, range from predators to herbivores, typically dioecious with external fertilization

Question 31

Summarize Class Clitellata

Answer 31

Earthworms and Leeches, monoecious, few or no setae, 3000 species, burrowing, no parapodia, low cephalization, move with antagonistic contraction or circular and longitudinal muscles, small protstomium, monoecious

Question 32

Define protstomium

Answer 32

lobe dorsal and anterior to the mouth that contains numerous sensory organs, including antennae, and eyes, like a head

Question 33

Summarize Subclass Hirudinea

Answer 33

Leeches, most freshwater, 500 species, no parapodia or setae, low cephalization, suckers anterior and posterior, coeliac sinuses, anticoagulant and anesthetic in saliva, don’t molt