Final Exam

Question 1

Metazoa arose from a flagellated, colonial ancestor supports what hypothesis

Answer 1

The origin of metazoas

Question 2

How many germ layers do poriferan embryos possess

Answer 2

none

Question 3

A shared derived trait is called a

Answer 3

synapormorphy

Question 4

What is a convergent (analogous) traint

Answer 4

a shared trait in unrelated organism

Question 5

polymorphism

Answer 5

when an organism or species has several stages or forms

Question 6

What is the life cycle of Cnidaria

Answer 6

Zygote > Planula larvae > Polyp (scyphistoma) > ephyra > medusa»»

Question 7

What are maternal effect genes

Answer 7

they code for morphogens invested in an egg prior to fertilization

Question 8

What principle states that no two species can occupy the same niche at the same time

Answer 8

Competitive Exclusion

Question 9

Interspecific Competition

Answer 9

a form competition in which individuals of different species compete for the same resource.

Question 10

Succession

Answer 10

The process of changing species inhabitants over time

Question 11

the degree to which a taxon is more numerous than its competitors in an ecological community

Answer 11

Ecological dominance

Question 12

Diploblastic organisms have which germ layers

Answer 12

endoderm and ectoderm

Question 13

Triploblastic organisms have which germ layers

Answer 13

endoderm, ectoderm, and mesoderm

Question 14

True jellyfish belong to the class

Answer 14

Scyphozoa

Question 15

Cell fate

Answer 15

programmed identify of cells

Question 16

first cell divisions where zygotic contents partition into smaller cells

Answer 16

Cleavage

Question 17

the biological process of an organism that causes it to form its shape

Answer 17

morphogenesis

Question 18

morphogens

Answer 18

a gradient of gene products that guide development

Question 19

Hydrozoa medusas reproduce _____

Answer 19

sexually

Question 20

a sponge feeds by

Answer 20

generating a current with collar cells; food is absorbed by collar cells

Question 21

a unusual feature of cnidarian neurons is

Answer 21

the capability to transmit nerve impulses in both directions across a neuron

Question 22

Nematocysts are

Answer 22

stinging cells; produced only by cnidarians; cnidocytes

Question 23

Skeletal elements of poriferans (spicules) are produced by cells called

Answer 23

Sclerocytes

Question 24

Calcareous or siliceous elements produced by sclerocytes in poriferans

Answer 24

spicules

Question 25

spongin

Answer 25

modified collagen produced by spongocytes

Question 26

(T or F) Ctneophores possess a single anus, whereas cnidarians possess two anal pores?

Answer 26

(False) Cnidarians do not have complete gut; no anus

Question 27

(T or F) Cnidarians produce contractile cells from ectoderm?

Answer 27

True

Question 28

(T or F) Cnidarians posses biradial symmetry, but ctenophores have a simpler, radial symmetry?

Answer 28

(False) Cnidarians have a radial symmetry and ctenophores have a biradial symmetry

Question 29

The velum is a characteristic of the ____ subclass ____ and provides what function

Answer 29

cnidarian; hydrozoa ; improves movement

Question 30

(T or F) Comb jellies have complete guts

Answer 30

True

Question 31

(T or F) hydrozoans have complete guts

Answer 31

(False) Cnidarians have a gastrovascular cavity

Question 32

(T or F) sponges have a complete gut

Answer 32

(False) they don't contain any guts

Question 33

At which stage do we begin to see development of the mesoderm germ layer

Answer 33

gastrulation

Question 34

cleavage of a zygote produces cells called

Answer 34

blastomeres

Question 35

name four of the 7 larvae forms of Poriferans

Answer 35

Cinctoblastula, calciblastula, amphiblastula, trachimella

Question 36

What are homeotic genes?

Answer 36

they cause the development of specific structures in plants and animals.

Question 37

What are the unique characteristics to animals

Answer 37

1) Blastula 2) Cell adhesion molecules including fibronectins and cadherins 3) Cell junctions 4) Extracellular Matrix