Transcript Phylum Nematoda BIO 2215 Oklahoma City Community College Dennis Anderson Phylum Nematoda • 12,000 species – 500,000 possible • Cylindrical body • Only longitudinal muscles • Noncellular cuticle with several.

Phylum Nematoda
BIO 2215
Oklahoma City Community College
Dennis Anderson
1
Phylum Nematoda
• 12,000 species
– 500,000 possible
• Cylindrical body
• Only longitudinal
muscles
• Noncellular cuticle
with several layers
• Pseudocoelomate
• Mouth and anus
2
Nematodes
• Found everywhere
–
–
–
–
Soil
Oceans
Polar ice
Hot springs
• Parasites of nearly all
plant and animal
species!
3
Uniramia
Echinodermata
Chelicerata
Chordata
Lophophores
Crustacea
Other Chordata
Arthropoda
Annelida
Hemichordata
Other
pseudocoelomates
Nematoda
Mesozoa
Sarcomastigophora
Ciliophora
Apicomplexa
Microspora
Mollusca
Nemertea
Platyhelminthes
Ctenophora
Cnidaria
Placozoa
Porifera
Myxozoa
4
Embryonic Development
• Protostome
– Blastopore becomes mouth
• Deuterostome
– Blastopore becomes anus
5
6
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Nematode Reproductive Systems
7
Dioecious
8
Dorsal and Ventral Nerve Cords
9
Caenorhabditis elegans
• Free living nematode
• Eutely
– Constant number of
cells
• 959 cells
– Development of every
cell is known
• Genome sequenced
• Compare genomes
10
Nobel Prize for Worms
• Sydney Brenner
– C. elegans since 1963
• Brenner, Sulston and
Horwite awarded
Nobel Prize in 2002
11
Ascaris lumbricoides
• Roundworm of man
• 1.2 billion people
– Many in southeast US
• Females lay 200,000
eggs a day
• Unsanitary habits
contaminate ground
• Night soil
12
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Life Cycle of Ascaris Lumbricoides
Source: Redrawn From Centers for Disease Control, Atlanta, GA.
13
Enterobius vermicularis
• Pin worm
• 50% of children in US
• Spread
– Fecal oral route
– airborne
14
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Life Cycle of Enterobius Vermicularis
Source: Redrawn From Centers for Disease Control, Atlanta, GA.
15
Hookworms
• Anterior end hooks
• Necator americanus
• Ancylostoma
duodenale
• Feed on blood
• Cause anemia
16
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Life Cycle of Necator Americanus
Source: Redrawn From Centers for Disease Control, Atlanta, GA.
17
Ancylostoma caninum
18
Cutaneous Larval Migrans
• Hookworms from
dogs and cats
19
Trichinella spiralis
• Trichina worm
• Pigs, bear, dogs, cats,
rats and man
• Trichinosis
– Encysts in muscles
20
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Life Cycle of Trichinella Spiralis
Source: (a) Redrawn From Centers for Disease Control, Atlanta, GA. (b) Photo © Steve Miller
21
Wuchereria bancrofti
• Lives in lymphatic
system
• Obstruct lymph to
cause swelling
– Elephantiasis
22
Elephantiasis
23
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Life Cycle of Wucheria spp.
Fig. 11.15
11-13
Source: Redrawn From Centers for Disease Control, Atlanta, GA.
24
Loa loa
• Eye worm
25
26
Dracunculus medinesis
• Fiery serpent
27
28
Dirofilaria immitis
• Dog heart worm
29
30
The End
31