Lecture 1: Animal Diversity

1. What are the 4 characteristics of animals? (these are not unique to animals)

1. Multicellularity 

2. Heterotrophy

3. Internal digestion

4. Motility

 What are the 3 synapomorphies for animals.

hox like genes, junctions between cells, extracellular molecules (collagen and proteoglycan)

Sponges are mostly ___ feeders.

Sponges lack ____.

1. Mostly marine filter feeders

2. Lack distinct tissue/organs (monoblastic)

Describe ctenophores

1. Have nerve net

2. Separate mouth / anal pores

3. Lack most Hox genes

(Diploblastic (chart tells us)

No distinct organs (chart tells us)

draw phylogeny for animals

describe placozoans

1. No nervous tissue 

2. No gut or other distinct organs

3. No mouth or anal pores

Diploblastic (chart tells u this)

describe cnidaria

1. (true jellies, corals, anemones, etc.)

2. Diploblastic

3. Have nerve tissue (nervous net)

4. Single opening to the gut (unlike ctenophora. cnideria , only have one opening to eat and poop out of). 

What kind of symmetry do triploblasts have and what relation does it have to an organism’s head? Also name the two clades in them

1. Bilateral symmetry (Capable of cephalization - formation of a head)

2. Clades are protostomes and deuterostomes 

name four animals in the protosomes clade

Includes mollusks, most worms, arthropods (insects, spiders, crustaceans) 

name the 4 animals in the deuterostomes’ clade

Includes echinoderms (starfish and see urchins), hemichordates (some worms), chordates, invertebrates.  

what 3 groups lack distinct organs/tissue?

1. Sponges

2. Ctenophores

3. Placozoans

name which groups are mono, diplo, and triploblastic out of (Sponges, Ctenophores, Placozoans, Cnidaria, Protosomes, Deuterostomes)

mono: sponges, diplo: ctenophores, placozoans, cnidaria triplo: protostomes, deuterostomes

 What are the different types of symmetry? Which groups have which type? What

advantage(s) do bilaterally symmetrical organisms have over radially symmetrical ones?

1. Bilateral symmetry (like how ur face is symmetrical when split between ur eyebrows) 

   1. Triploblasts have this

   2. If u have this Cephalization,  formation of a head end (meaning they have a distinct front end), happens

2. radially symmetrical (symmetrial like how an umbrella is) 

   1. Diploblasts have this

What are the major differences between protostomes and deuterostomes?

1. Protosomes 

   1. blastopore becomes mouth, end becomes the anus

   2. nerve cord runs down belly and digestive track runs down back 

2. Deuterostomes 

   1. The blastospore becomes anus, end becomes the mouth. 

   2. nerve cord runs down back and digestive track runs down belly

diff bwtween diplo and triploblasts.

Diploblastic(have Ectoderm and Endoderm): 

Triploblastic(have Ectoderm, mesoderm, endoderm)

what is the difference between the endoderm, mesoderm, ectoderm

1.Ectoderm: skin and nervous system 

2.Mesoderm (meat) : muscle and bones

3.Endoderm: digestive tract and lungs