Lecture 30 - Invertebrates I

Question 1

What is evo-devo?

Answer 1

study of evolutionary developmental biology

Question 2

What are the 2 aspects of the Genetic Theory of Morphological Evolution?

Answer 2

1. Morphological diversity evolves through alterations in functionally conserved proteins
2. Changes occur through mutations in promoter sequences of regulatory genes + their target genes that participate in developmental pathways

Question 3

What is a transcription factor?

Answer 3

protein that binds to specific sequences in the promoter of a gene

Question 4

What does a transcription factor do?

Answer 4

o Controls transcription of genetic info from DNA to RNA

Question 5

3 Classes of Phylum Porifera

Answer 5

(sponges)

1. Glass
2. Demosponges
3. Calcareous

Question 6

How do Phylum Porifera eat?

Answer 6

• Suspension feeders

- Choanocytes line spongocoel to trap food in collars

Question 7

What kind of reproductive system do Phylum Porifera have?

Answer 7

-Sequential hermaphrodites

Individuals produce both sperm + eggs

Question 8

(Phylum Porifera) Where do gametes arise?

Answer 8

-choanocytes or amoebocytes

Question 9

(Phylum Porifera) 3 steps of reproduction

Answer 9

1. Eggs are typically retained, sperm carried out osculum by water current
2. Sperm drawn into neighboring individuals
3. fertilize eggs in mesophyll

Question 10

Sponges are capable of extensive ________

Answer 10

regeneration (replacement of lost parts)

Question 11

(Phylum Porifera) Defense

Answer 11

Sponges produce variety of bioactive metabolites (antibiotics)

Question 12

(Phylum Porifera) What cells could be rudimentary sensory organs?

Answer 12

• Globular cells may represent rudimentary sensory organs

- Metazoans were already in possession of proto-neural cells

Question 13

4 classes of Phylum Cnidaria

Answer 13

1. Hydrozoa
2. skypozoa
3. cubizoa
4. anthozoa

Question 14

(Phylum Cnidaria) basic body plan

Answer 14

• sac with central digestive compartment (gastrovascular cavity)
• single opening to cavity functions as both mouth and anus

Question 15

(Phylum Cnidaria) What are the two variations in body plans?

Answer 15

1. Polyp (sessile)

2. Medusa (floating jellies)

Question 16

What are 3 characteristics of Polyp?

Answer 16

1. Cylindrical, adhere to substratum by aboral end
2. Extend tentacles
3. Wait for prey

Question 17

What are 2 characteristics of Medusa?

Answer 17

1. Flattened, inverted versions of polyps

2. Drift passively by contracting bell-shaped body

Question 18

Must Phylum Cnidaria exist as either polyp or medusa?

Answer 18

• some exist as polyps
• some exist as medusas
• others pass sequentially through both stages in life cycle

Question 19

How do phylum cnidaria eat?

Answer 19

• Cnidocytes on tentacles for defense/prey-capture

- carnivores

Question 20

What are nomatocystes?

Answer 20

inject poison into pretty after chemo-mechano stimulation

Question 21

How does symbiosis work between phylum cnidaria and anemone work?

Answer 21

• mutual symbiosis
• Fish defends host, uneaten food/feces feed anemone
• Avoids being stung via sugar-based mucous coating

Question 22

Epidermal + gastrodermal cells have ______________

Answer 22

contractile fibers of bundled microfilaments

Question 23

Where did true muscles appear first?

Answer 23

triploblastic animals

Question 24

(Phylum Cnidaria) How are movements controlled?

Answer 24

• non-centralized nerve net

- Associated with simple, radially distributed sensory receptors