WORM DISSECTION

VIDEOS https://www.youtube.com/watch?v=5ppBoPeSpxA Planaria regeneration https://www.youtube.com/watch?v=WaYc7ezX2gI 10 Facts about Earthworms https://www.youtube.com/watch?v=9Q9gh1k99rY Annelid Worms

KIDSPIRATION by Riedell

NAMING Kingdom: Phylum: Class: ANIMALIA Annelida “little rings” OLIGOCHAETA “few bristles”

SETA (plural: setae) BRISTLES on VENTRAL surface http://www.pgjr.alpine.k12.ut.us/science/whitaker/Animal_Kingdom/Earthworm/Earthworm.html

Segmentation Compartments allow individual parts to move independently Damage insurance If one section is damaged, others can still function http://sps.k12.ar.us/massengale/earthworm_dissection.htm BIODIDAC

SEGMENTED WORMS Earthworms play an important role in soil fertility “intestines of the earth” -Aristotle Return nutrients to soil by decomposing dead leaves and organic matter Burrowing allows air and water to penetrate to roots Tunnels loosen soil so roots can grow more easily http://www.semioticon.com/seo/N/images/niche_3.png

Terms to Know Dorsal: TOP of organism Ventral: BOTTOM of organism Anterior: near the HEAD (front) Posterior: near the BACKSIDE

WHICH END IS WHICH? CLITELLUM = ring Doesn’t go all the way around Image by Riedell/VanderWal©2005 CLITELLUM = ring Doesn’t go all the way around Closest to anterior end Makes mucous for reproduction

2 opening digestive system Image by Riedell/VanderWal©2005 Image by Riedell/VanderWal©2005 MOUTH ANUS Prostomium covers/protects mouth opening senses light/dark, chemicals (food), vibration

EXTERNAL STRUCTURES DORSAL BLOOD VESSEL CAMOUFLAGE

CUTICLE (non-cellular protective layer) http://www.flushing.k12.mi.us/srhigh/tippettl/biology/lum/cuticle.html http://www.flushing.k12.mi.us/srhigh/tippettl/biology/lum/cuticle.html

INTERNAL STRUCTURES

COELOM = space around organs Image by Riedell/Vanderwal ©2005

SEPTUM (pl. SEPTA) Dividing walls separate coelom into compartments Fluid in coelom provides support = HYDROSTATIC SKELETON (water skeleton) Image by Riedell/Vanderwal ©2005 Image from: BIODIDAC

CLOSED circulatory system DORSAL BLOOD VESSEL VENTRAL BLOOD VESSEL

DORSAL BLOOD VESSEL Image by Riedell/Vanderwal ©2005 Images by Riedell/VanderWal©2005 Image by Riedell/Vanderwal ©2005

5 AORTIC ARCHES act as “heart” to pump blood Image by Riedell/Vanderwal Image by Riedell/Vanderwal ©2005

Image by Riedell/Vanderwal ©2005 PHARYNX PHARYNX

INTERNAL STRUCTURES CROP-stores food waiting to be digested Image by Riedell/Vanderwal ©2005   CROP-stores food waiting to be digested GIZZARD- grind and mash food

INTESTINE- absorbs nutrients Images by Riedell/Vanderwal ©2005 WORMS HAVE ADAPTATIONS for eating “SOIL” 1. REALLY LONG INTESTINE- so food spends long time passing through 2. TYPHLOSOLE- ridge inside increases surface area for more absorption

EXCRETORY SYSTEM http://www.pleasanton.k12.ca.us/avhsweb/thiel/apbio/review/excretory.html Osmoregulation: Collect & excrete NITROGEN WASTE to maintain HOMEOSTASIS Use the NEPHRIDIUM (act like a kidney)

SEXUAL REPRODUCTION Earthworms are hermaphrodites HAVE BOTH MALE & FEMALE REPRODUCTIVE ORGANS in same worm

EXTERNAL STRUCTURES MALE GENITAL PORE- releases sperm to give away http://sps.k12.ar.us/massengale/earthworm_dissection.htm EXTERNAL STRUCTURES MALE GENITAL PORE- releases sperm to give away FEMALE GENITAL PORE- releases eggs OPENINGS to SEMINAL RECEPTACLES- receive sperm from other worms when trade

SEXUAL REPRODUCTION EXTERNAL FERTILIZATION Produce a COCOON made of MUCOUS and CHITIN (tough carbohydrate) Baby worms hatch after a few weeks

REPRODUCTIVE SYSTEM SEMINAL RECEPTACLES Image by Riedell/Vanderwal©2005 SEMINAL RECEPTACLES Store sperm received from other worms

REPRODUCTIVE SYSTEM SEMINAL VESICLES STORE WORM’S OWN SPERM Image by Riedell/Vanderwal©2005 STORE WORM’S OWN SPERM TO “GIVE AWAY”

  UNDERNEATH DIGESTIVE SYSTEM VENTRAL NERVE CORD Image by: Riedell/Vanderwal © 2005   UNDERNEATH DIGESTIVE SYSTEM VENTRAL NERVE CORD (nerves usually white) VENTRAL BLOOD VESSEL (usually dark)

BODY PLANS are also flipped! Most INVERTEBRATES have a DORSAL HEART and a VENTRAL NERVE CORD ALL VERTEBRATES have a DORSAL NERVE CORD and a VENTRAL HEART.