Week Two: Nematodes an Intruduction (Chapter Three) Flashcards Preview

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Flashcards in Week Two: Nematodes an Intruduction (Chapter Three) Deck (17):
1

What are nematodes and what are the three basic types?

Roundworms
-Free living
-Nematodes that parasitize plants
-Nematodes that parasitize domesticated animals, wild animals, and humans

2

What are the most numerous and diverse group of parasites on earth?

Nematodes

3

Where are nematodes found in the body?

-GI tract
-Circulatory system
-Respiratory tract
-Urogenital system
-Eye

4

What are plant nematodes responsible for?

10% loss of cultivated crops

5

What are some key morphologic features of nematodes?

-Multicellular
-Unsegmented
-Elongate
-Rounded on both ends
-Circular in cross section
-Bilaterally symmetric

6

What are some external morphologic features of nematodes?

-Covered by a thin cuticle which extends into all body openings (secreted by hypodermis)
-Lateral flattened expansions at anterior end
-Lateral flattened expansion at posterior end

7

What is the lateral flattened expansions at the anterior end of a nematode called?

Cervical alae

8

What is the lateral flattened expansion at the posterior end of a nematode called?

Copulatory bursa

9

What enables nematodes to move?

The somatic muscular layer beneath the hypodermis

10

What is the pseudocoelom?

Specialized muscles that line the body cavity to aid in feeding and reproduction

11

Describe the digestive system in a nematode
(Explain the difference between male and female as well)

Long, straight tube extending from mouth to anus
Females have a rectum
Males have a cloaca

12

What does dioecious mean?

Separate sexes

13

Explain the first stage of the life cycle of a nematode

1.Female produces egg (single cell stage within egg shell)
2. Original cell divides into 2, 4, 8, ect..
3.Morula stage
4.Tadpole stage
5.Developed into a fully formed first stage larava within egg shell

14

Explain the second stage of the life cycle of a nematode

1.Larva emerges from egg shell and molts
2.Develops into second stage larva

15

What happens between second and third stage of a nematodes (larva) life cycle?

Molts

16

What does the third stage of a larva (nematodes) lifecycle mean?

It is infective for the definitive host

17

Where can the first three stages of a larva (nematode) develop?

In external environment or within intermediate host