Intro- Year 3

Question 1

What are helminths?
What are the different types of helminths?

What are protozoa?

What are arthropods?

Answer 1

Helminth- worm
nematode (round worm), platyhelminth (cestodes and flukes)

Protozoa- single-celled organisms

Arthropods- arachnids, insects

Question 2

What are the general features of nematodes?

What are the male repro organs?
What are the female repro organs?

Answer 2

• Round worms
• Cylindrical
• Radial symmetry
• Both free-living and parasitic stages

Male- testis, vas deferens, cloaca

Female- ovary, uterus, vulva

Question 3

What are the organs of the nematode digestive system?

How can female and male nematodes be separated generally?

Answer 3

Digestive system- buccal cavity, oesophagus, intestine, anus

Females are generally larger- females have eggs in the uterus, males have decorated tails

Question 4

Can you name parasites 1-6?

Answer 4

Question 5

What are the two platyhelminths of importance?

Answer 5

Trematodes- flukes

Cestodes- tapeworms

Question 6

What are the general characteristics of trematodes and cestodes?

Answer 6

Trematodes

• Indirect life-cycle
• Dorso-ventrally flattened
• Hermaphrodite
• No body-cavity- gut embedded within the parenchyma
• Outer layer- tegument

Cestodes

• Segmented
• No gut
• Always parasitic
• Indirect life cycles
• Stage in intermediate host- metacestode
• Hermaphrodite- male and female repro organs
• Outer layer- tegument

Question 7

How can protozoa reproduce?

How can protozoa locomote?

Answer 7

Sexually- syngamy
gametes fuse to form a zygote (oocysts)

Asexual
binary fission, schizogony

Locomotion-
Gliding- tachyzoites
Flagella- trypanosomes

Question 8

What is the feeding stage of protozoa?

How are protozoa transmitted?

Answer 8

Trophozoite- feeding stage

Transmission

• Direct- resistant cysts, active protoza
• Indirect- resistant cysts
• Vector-borne- mosquitoes, ticks
• Mechanical

Question 9

What does the term ‘dioecious’ mean?

Answer 9

Dioecious- separate males and females