Transcript Earthworms and the Environment

Animals
Sponges
Cnidarians
Worms
What is an Animal?
Characteristics
 Made of Cells
 Heterotrophs (cannot make own food)
 Organized Structure
a. Cells – Basic Unit of Life
b. Tissues – Organized Cells
c. Organs – Organized Tissues
d. Organ Systems -Organ Teams
Animal Information
Functions
1) Obtain Food
2) Obtain Oxygen
3) Movement
4) Reproduction
a. Asexual (1 parent)
b. Sexual (2 parents)
Classification
1) Evolution – based on
science information
2) 2 Levels
a. Vertebrates (backbone)
b. Invertebrates
3) System based on:
a. Relationship to others
b. Body Structure
c. Development
d. DNA
Animal Classification - Hypothesis
Vertebrates
 Backbones
 Birds
 Reptiles
 Mammals
 Amphibians
 Fish
Invertebrates
 No Backbones
 97% of Animal Population
 Sponges
 Cnidarians
 Echinoderms
 Flatworms
 Roundworms
Worms
Characteristics
 Invertebrates
 Long, narrow body
 No legs
 Bilateral symmetry
(Head/Tail/organs)
 Nervous system
 Reproduction
Sexual
Asexual
Classification
 Flatworms
Free living - planarians
Parasite – tapeworms, flukes
Scavengers - planarians
 Roundworms
Moist environments
Tiny and abundant
 Segmented worms
Linked sections
closed circulatory system
Earthworms and the Environment
7th Grade
Earthworms – Phylum Annelida
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Segmented worms (earthworm and leeches)
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Scientific Name: Lumbricus terrestris
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Earthworms – Important to Farmers
 Earthworms improve the soil in the following ways:
 They eat their way through the soil
 They mix the ingested material helping to improve
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soil
Depositing soil in different places and mixing
horizons.
Improve drainage of heavy clay soils
Introduces more air into the soil.
When they die they further increase the amount of
organic matter
Earthworm Anatomy
Earthworm - Vocabulary
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Muscular-Skeletal
Setae - bristles on segments that help with movement
Muscles – two sets, one (long/ thin) one (for width)
Digestive System
Nervous - Simple brain, Nerve cord
Circulation - Blood , Blood vessels , Aortic arches – 5 simple hearts
Respiration - No lungs , Oxygen exchange through its skin, Gives off carbon dioxide
Skin must stay moist for survival
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Reproduction – Sexual,
Hermaphroditic – Both Male and Female Parts
Eggs fertilized by the sperm of another worm
Batch of eggs laid at one time
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Excretion - Nephridin - lead to pores in skin for waste removal
Symmetry - Bilateral symmetry
Coloration - Brown, tan, etc.
Earthworm - Vocabulary
 Digestive System
1) Mouth – Gathers dirt with plant/animal matter
2) Esophagus – Moves food from mouth to crop
3) Crop - Stores the food
4) Gizzard - Grinds the food
5) Intestines - Move nutrients to the body
6) Anus - Food removal
Earthworm Anatomy
Earthworm Anatomy –
Mouth Section
Earthworm – Internal Anatomy
Level 2 Earthworm Anatomy
Earthworm - Reproduction
 Hermaphroditic –
Both Male and Female Parts
 Need two worms for fertilization
Earthworm – Circulatory System
1 – Aortic arches (heart)
2 /3 – Blood Vessels
Earthworm – Digestive System
1 Anus
2 Intestine
3 Cerebral ganglion
4 Prostomium
5 Mouth
6 Nerve collar
7 Segmental ganglion
8 Pharynx
9 Esophagus
10 Segmental nerve
11 Crop
12 Gizzard
13 Nerve
Earthworm - Dissected