invertebrates 3 for each major group, think...

4/18/19

1

Invertebrates 3 •  More Protostomes

•  A little more about earthworms – Ecdysozoa

•  Nematodes (briefly)

• Arthropods –  Crustaceans –  Chelicerates –  Insects

•  Deuterostomes •  Echinoderms •  Chordates (all of next week)

April 19, 2019

For each major group, think about:

• A familiar example • What is the basic body plan?

–  i.e. Does it have a Head? Muscles? Bilateral symmetry?

• How does it eat? • How does it move? • How does it reproduce?

Figure 33.UN03

Porifera Cnidaria Lophotrochozoa Ecdysozoa Deuterostomia

Bilateria

Mollusca Annelida

Annelida

Epidermis

Intestine

Clitellum

Anus

Thin cuticle

Ventral nerve cords Circulatory system vessels

Mouth

Cerebral ganglia

Giant Australian earthworm

earthworm

Earthworm reproduction

Link to video

Figure 33.UN04


4/18/19

2

The Ecdysozoa

Why do ecdysozoans molt?

Phylum Nematoda

C. elegans in the lab

https://www.youtube.com/watch?v=zjqLwPgLnV0

Phylum Arthropoda

CRUSTACEANS

Jointed appendages can have many shapes and functions

Figure 23.30 Two Segmented Body Plans (Part 1)

Crustacea

4/18/19

3

Chelicera Figure 33.33

Heart Brain

Eyes

Poison gland

Pedipalp Chelicera

Book lung

Sperm receptacle

Gonopore (exit for eggs)

Silk gland

Spinnerets

Anus

Ovary

The Insects

By far the most species-rich group of animals!

Figure 33.35

Abdomen Thorax Head

Heart Cerebral ganglion

Mouthparts Ventral Nerve cords

Ovary

Vagina

Anus

Archaeognatha (bristletails; 350 species)

Zygentoma (silverfish; 450 species)

Winged insects (many orders; six are shown below)

Complete metamorphosis Incomplete metamorphosis Hemiptera (85,000 species)

Coleoptera (beetles; 350,000 species)

Diptera (151,000 species) Orthoptera

(13,000 species)

Hymenoptera (125,000 species)

Lepidoptera (120,000 species)

Proboscis

Insect life cycles

4/18/19

4

Insect mouthparts

Chewing Piercing

Insects are the only invertebates that fly

Figure 33.UN05


Echinoderm Diversity

Echinoderm larvae are bilaterally symmetrical

Echinoderms Short digestive tract

Stomach Anus

Spine Gills

Radial nerve

Gonads

Tube feet Water Skeleton

Ring canal

Digestive glands

invertebrates 3 for each major group, think...

Documents