PA2: Intro to arthropods

Question 1

Define arthropods.

Answer 1

Invertebrates w/ hard chitinous exoskeleton, segmented body & jointed limbs.

Question 2

How do arthropods grow?

Answer 2

By ecdysis (la mue ou moulting).

Question 3

What are the main divisions of arthropods?

Answer 3

Insecta & arachnida

Question 4

What are the characteristics of insecta?

Answer 4

Adults have 3 pairs of legs & 1 pair of antennae.
Undergo partial/complete metamorphosis during lifecycle.
Have a distinct head, thorax & abdomen.

Question 5

What are the characteristics of arachnida?

Answer 5

Nymphs & adults have 4 pairs of legs & NO antennae.
No obvious body segmentation.
Undergo partial metamorphosis during lifecycle.

Question 6

What are the reproductive strategies of arthropods (and other parasites in general)?

Answer 6

R strategy: adults produce many offsprings, not many survive.
K strategy: adults produce few offsprings but most make it to reproductive stage.

Question 7

What is meant by arthropods can be mechanical vectors?

Answer 7

They transmit pathogens but the pathogen does not interact with the parasite’s lifecycle.

Question 8

What is meant by arthropods can be biological vectors?

Answer 8

They transmit a pathogen that develops at least partly in the arthropod.

Question 9

What are examples of arthropods as mechanical vectors?

Answer 9

Tick pyaemia
Summer mastitis transmitted by flies

Question 10

What are examples of arthropods as biological vectors?

Answer 10

West Nile virus transmitted by mosquitoes.