Earthworms Posterior Tail End Anus Anterior Head End

Earthworms

Posterior / Tail End Anus Anterior / Head End Clitellum Mouth Setae Seminal Receptacles

Ganglia Pharynx Hearts Seminal Receptacles Testes Seminal Vesicles Esophagus Crop Ovaries Gizzard Sperm Duct Intestine Dorsal Blood Vessel Central Nerve Cord Ventral Blood Vessel

Setae • Appearance: Tiny bristles (feel them) • Location: Entire length of worm. • Function: Tiny hairs to help with movement + sex.

Clitellum • Appearance: Knob • Location: Near center of length. • Function: Secretes fluid to enclose fertilized eggs.

Mouth • Appearance: Hole • Location: Front / Shorter End • Function: Food intake/eating

Ganglia/Brain • Appearance: Small flesh-colored tissue blob • Location: Directly behind mouth. • Function: Control organs + responses.

Pharynx • Appearance: Round Lump • Location: Directly behind mouth + ganglia. • Function: Start food break down.

Hearts/Aortic Arches • Appearance: Black finger nail clippings • Location: Behind Pharynx. • Function: Circulate blood.

Esophagus • Appearance: Skinny tube • Location: Behind Pharynx (center). • Function: Carry food to crop + gizzard.

Crop • Appearance: Round Lump (feels like a bag) • Location: Behind hearts + reproductive organs. • Function: Food storage before digestion.

Gizzard • Appearance: Round lump (feels muscular) • Location: Behind crop. • Function: Grind up food.

Intestine • Appearance: Long Tube • Location: Along back length (leaving gizzard). • Function: Absorb nutrients + excrete waste.

Dorsal Blood Vessel • Appearance: Thin dark line • Location: Along back length (on top). • Function: Carry blood.

Ventral Blood Vessel • Appearance: Thin dark line • Location: Along back length (on bottom). • Function: Carry blood.

Seminal Receptacles • Appearance: Fleshy colored lumps/bits • Location: Behind hearts. • Function: Receive sperm for egg fertilization.

Seminal Vesicles • Appearance: Small fleshy lumps/bits • Location: Behind hearts. • Function: Release + store sperm.

Ovaries and Testes • Appearance: Small fleshy lumps/bits. • Location: Behind hearts. • Function: Produce eggs and sperm.

---Dissection Notes--1. Lie worm on its belly (rounded/darker side pointed up). 2. Identify clitellum. 3. Carefully cut from MOUTH CLITELLUM 4. Carefully peel back skin. 5. Identify organs.

External Dorsal: Mouth Clitellum Dorsal Blood Vessel (Dark Line) Anus

External Ventral: Mouth Clitellum Genital Setae Sperm Ducts Female Genital Pores

Internal: Pharynx Esophagus Crop Intestine Gizzard Seminal Vessicles Aortic Arches Seminal Recepticles Ganglia (Brain)

Internal w/o Digestive… Nerve Cord (Like our Spinal Cord) Seminal Receptacles

Let’s watch a demo… • https: //www. youtube. com/watch? v=u 9 HHS 1 u. PFSo