chapter 36 section 1 Flashcards Preview

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Flashcards in chapter 36 section 1 Deck (18):
1

what is a pharynx

muscular tube where food is ingested in planarians

2

tegument

sheet of fused cells on the external surface of a fluke

3

fluke

a leaf shaped flatworm that parasitizes many kinds of animals

4

tapeworm

live in the intestines of almost all interior vertebrates

5

primary host

host where adult parasite derives nourishment

6

intermediate host

host where larvae derive their nourishment

7

flatworms are the simplest animals with

bilateral symmetry

8

the gastrovascular cavity of a flatworm

has a single opening

9

one difference between free living flatworms and parasitic flatworms is that

parasitic flatworms usually have a simpler structure

10

the eggs of the blood fluke "Shistosoma"

leave the primary host in feces or urine

11

the primary hosts of beef tapeworms are

humans

12

what is the primary host of a blood fluke

humans

13

what is the intermediate host of a blood fluke

snails

14

how does a blood fluke enter its primary host

a tailed larva bores through exposed skin of a human

15

what stage of the beef tapewrom life cycle is spent inside a cyst

the larval stage

16

how do planarians eliminate excess water from their bodies

Flame cells collect excess water, which is then transported
through excretory tubules and excreted from
numerous pores scattered over the body surface.

17

how do planarians and tapeworms differ in their ability to detect light

Planarians detect the intensity and direction of
light with two eyespots; tapeworms cannot detect
light.

18

some people mistakenly believe that all organisms are perfectly adapted to their environments. what aspect of blood fluke reproduction suggests that these flatworms are not perfectly adapted to the environment inside their human hosts

The eggs sometimes block blood vessels, causing
a disease that may kill the host. A parasite that
kills its host may not be perfectly adapted to its
environment.