Flashcards in Arthropods II: Metamorphosis Hormones Deck (64)
What the 4 major groups of Arthropods?
How many body regions do myriapods have?
What are the two regions of myriapods?
head and runk
chelicerates have ___ body regions
what are the two body regions of chelicerates
- chepalothorax: appendages
- abdomen: no appendages
How many pairs of appendages do chelicerates have?
what are the 6 pairs of appendages chelicerates have?
2: copulatory organs, pinchers
3, 4, 5, 6: walking legs
what are the three body regions of custaceans
what makes up the group of hexapods?
insects and other groups
what are the three body regions of a hexapod
1. head: antennae, mouthparts
2. thorax: 3 pairs of walking legs (possibly wings)
3. Abdomen: no appendages
are springtails insects?
no but they are considered hexapods
when did wings evolve?
around 320 mya
the wing of a ____ and the gill of a ___ ____ are homogolous
insect ; cray fish
how do most insects and myriapods breathe?
through holes (spiracles) open into tubular tracheae which branch to finer tubes
- carry O2 to body cells
What kind of circulatory system do arthropods have?
what drives hemolymph into hemocoel
dorsal tubular heart with pores
what kind of valves do arthropods have?
one way valves
most species of arthropods are
most species of arthropods...
Arthropods can reproduce on ___ and in ____
land ; water
How do Arthropods reproduce on land?
- internal fertilization
- some use spermatophores (= packets of sperm_
How do Arthropods reproduce in water?
internally (crabs) or externally (barnacles)
How do males prevent females from eating their sperm?
by giving it this extra layer that takes a long time to eat
Why do females compete for males?
because they get nutrients from the males
What does moulting enable?
changes in morphology aka metamorphosis
when do insects stop moulting?
when they are adults
what kind of Arthropod continues moulting as adults?
Indirect of holometabolous development