Midterm Review

Question 1

Morphology – what structures are present in

what group? What do they do?

Answer 1

Structures and functions, mostly apomorphies for the particular groups.

Question 2

How can groups be differentiated?

Answer 2

Morphology, phylogenetic, group specific apomorphies.

Question 3

What are diagnostic characters of

species/groups?

Answer 3

Morphology, Genetics, Apomorphies.

Question 4

What are the main taxonomic groups within

Annelida?

Answer 4

Polychaetes and Clitellates.

Question 5

Main differences between Cnidaria and

Ctenophora?

Answer 5

Multiciliate cells, gastrulation is invagination or epiboly (not ingression), mouth and anus, muscles in mesoglea (triploblastic?), colloblasts (vs. cnidocytes), apical sense organ, cydippid larva and direct life cycle (no polyp), no asexual reproduction.

Question 6

What character(s) would you focus on if you
are trying to identify a XXX?

Answer 6

Usually should focus on the Apomorphies of the group, and how they differ within the group.

Question 7

Systems: how do organisms reproduce, breath,

excrete, move, defend, detect etc.

Answer 7

Musculature, Digestion, Internal System, Excretion, Reproduction/Development.

Question 8

Larval Types

Answer 8

Larval vs. Adult strategies (Ex; medusa and polyp phase)

Question 9

Habitats – how are organisms adapted to the
environment they live in? – marine,
freshwater, terrestrial

Answer 9

Again, apomorphies are usually important in these questions.

Question 10

What kinds of larva(e) are found among

Annelid species?

Answer 10

Trochophore larvae that live as plankton. Many species emerge as miniature adults (all Clitellates).

Question 11

How do Bryozoans reproduce?

Answer 11

Both sexual and asexual reproduction - Asexual by budding off new zooids and by using statoblasts; Sexual by shedding both sperm and eggs into water (since they’re hemaphroditic), or by producing free swimming larvae in brood chambers that eventually leave the colony and settle elsewhere.

Question 12

Describe the variety of construction strategies

observed in the sponges.

Answer 12

Asconoid - Least advanced

Synconoid -

Leuconoid - Most advanced (and biggest)

Question 13

If this phylogeny and these tips & traits – how

would you describe X & Y

Answer 13

?

Question 14

What kinds of feeding modes can be found
among Annelida? How are they different from
each other? How did they evolve from a
putative ancestral mode?

Answer 14

Pharynx and jaws for species that feed on large particulates. Ciliated tentacles or pump water through burrows for filter feeding. Everted pharynx.

Question 15

Why are some groups so much more diverse

than others?

Answer 15

Due to selection pressures, time since last ancestor, range, ect.

Question 16

Parasitism

Answer 16

Especially in protozoa and annelids.

Question 17

Direct versus indirect/Metamorphosis

Answer 17

Direct: When the juvenile phase closely resembles the adult.

Indirect: When the juvenile looks greatly different from the adult.

Question 18

Sexual/Asexual

Answer 18

Sexual: Uses gametes, usually produced by male and female, but hermaphrodites exist.

Asexual: Fission, budding, fragmentation, or parthenogenesis.

Question 19

Budding/Regeneration

Answer 19

Budding: A form of asexual reproduction (example: hydra)

Regeneration: Similar to budding, but when a limb is lost, it can be regrown.

Question 20

Explain the life cycle of XXX

Answer 20

Direct vs. indirect metamorphosis can be important for these questions, as is parasitism.

Question 21

What is the difference between the XXX and

YYY life cycles?

Answer 21

Again, one could use direct metamorphosis, and one could be indirect. Good example is within the annelids.