Quiz 7- arthropoda, echinodermata Flashcards
List the organisms known to have chelicerae
Subphylum Chelicerata
Define chelicerae
either of a pair of appendages in front of the mouth in arachnids and some other arthropods, usually modified as pincer-like claws
general characteristics of arthropoda
3 tissue layers
coelom
complete gut
bilateral symmetry
external cuticle made of chitin
segmentation + jointed appendages
rigid skeleton- molting necessary
sometimes have antennae that can taste + smell
compound + simple eyes
Orders of subphylum Chelicerata
Xiphosura and Pycnogonida
Chelicerata general characteristics
body divided into TWO major sections
1st section has 6 pairs of appendages
Subphylum Chelicerata, Class Pycnogonida
most common in shallow water, but some larger ones found in deep water
Usually consume soft-bodied invertebrates with proboscis
Usually have EIGHT walking legs
legs are thin enough that they can efficiently absorb oxygen thru diffusion
Subphylum crustacea general characteristics
Head with 2 pairs of antennae & specialized mouthpart appendages
Feeding and/or walking appendages on thorax (mid-section)
Posterior abdomen may have appendages used for respiration or swimming
Great range of feeding adaptations: crabs are largely carnivores, barnacles are suspension feeders, amphipods are detritus feeders
Describe Horseshoe Crab reproduction.
Breeding - Spring and Summer in NE US
Migrate to shallow coastal waters (notable in Delaware bay area!)
Male latches on back of female and fertilizes eggs while they are laid in the sand
Females can lay between 60,000 and 120,000 eggs
Eggs take about 2 weeks to hatch
Differentiate between the Xiphosura and Pycnogonida.
horseshoe crabs vs sea spiders
List the major classes of (subphylum) Crustacea.
Malacostraca
Thecostraca
List the major orders of class Malacostraca.
Decapoda
Stomatopoda
Decapoda
Crabs + lobsters
DECA –> 10 legs
lobsters- live in crevices/burrows on the seafloor
3/5 of the pairs of legs have claws
Stomatopoda
mantis shrimp
Thecostraca
barnacles
Understand how the water vascular system works, and what major phylum of invertebrates it is associated with.
ECHINODERMATA
water exchanged thru a madreporite (dorsal sieve plate: eg: starfish mouth)
Relief valves (pipettes) and water movement together cause pressure + suction
Tube feet used for suction + mucus secretion, (+ locomotion in sea urchins)
