Arthropods and Echinoderms Flashcards
What is a major challenge for terrestrial arthropods?
loss of water
Do Arthropods have an excretory system?
yes
What is the unique excretory system of Arthropods called?
Malpighian tubules
What do Malpighian tubules do?
eliminate nitrogenous wastes as concentrated uric acid or guanine; a way to remove ammonia without having to dilute it in water
What are Malpighian tubules associated with?
digestive system
What do arthropods undergo?
ecdysis
What is ecdysis?
molting
Why do arthropods undergo ecydysis?
for growth or replacement of exoskeleton
Where do arthropods live?
aquatic and terrestrial environments
What do aquatic arthropods have to breathe with?
gills
What do gills act as?
both respiratory and excretory organ
What other animals excrete uric acid like arthropods?
lizards and birds
How do arthropods fertilize?
internally
What is the significance of internal fertilization?
there is a higher chance of reproductive success
What are the sub phylum of Arthropods?
Chelicerata, Myriapoda, Crustacea, Hexapoda
What animals are chelicerata? (give examples)
Arachnids (spider, ticks, scorpions, mites, and horseshow crabs)
What are the anterior most appendages on Chelicerates called?
Chelicerae
What is the function of chelicerae?
function as fangs or pinchers
How are the bodies of Chelicerates divided?
2 main tagmata`
What are the 2 tagmata of Chelicerates?
Prosoma and Opisthosoma
What makes up the prosoma?
bears all appendages
What makes up the opisthosoma?
contains the reproductive organs
Where is the prosoma located?
anterior (front)
Where is the opisthosoma located?
posterior (back)
What are tagmata?
functional segments of the body
What is the prosoma a merger of?
head and thorax
What is the diet of most arachnids? What is the exception?
carnivorous; mites
What is the diet of mites?
herbivorous
Are there parasitic arachnids?
yes, ticks
How do spiders catch prey?
either in silk webs or hunt their prey
How do spiders make webs?
silk protein forced out of spinnerets on the posterior of abdomen
What do all spiders have?
poison glands leading through their chelicerae
Are spiders important?
yes, they are necessary for the ecosystem
What are two venomous spiders in the US?
black widow and brown recluse
What order of Chelicerates is the most diverse?
mites and ticks
What size are most mites?
small
What is the body of a mite like?
Cephalothorax and abdomen fused into an unsegmented ovoid body
What size are most mites?
larger than ticks
What is the diet of ticks?
ticks are blood-eating parasites
Do ticks carry diseases?
yes
What diseases can ticks carry?
spotted fevers, lyme disease
What is the body of Myriapoda like?
a head followed by numerous segments
What animals make up Myriapods?
centipedes and millipedes
What do centipedes eat?
carnivorous (eat insects)
What do millipedes eat?
largely herbivores (or consume organic material)
Do centipedes have a stinger/pincher?
yes
Do millipedes have a stinger/pincher?
no
Do millipedes or centipedes have more legs?
millipedes have more legs
How many legs per segment do millipedes have?
two on some or all segments
How many legs per segment do centipedes have?
one leg pair on each segment
Are Crustaceans primarily aquatic or terrestrial?
aquatic
What animals are Crustaceans?
crabs, shrimps, lobsters, barnacles
How many tagmata do Crustaceans have?
three
How do the two most anterior tagmata fuse?
fuse to form a cephalothorax
What are mandibles?
biting jaws
What are the jaws of Crustaceans called?
mandibles
Are most Crustaceans hermaphroditic or dioecious?
dioecious
What Crustacean is not dioecious?
barnacles (hermaphroditic)
What distinguishes Arthropods?
jointed appendages
How do barnacles move?
sessile as adults, free-swimming as larvae
How do barnacles eat?
filter feeders
What is the largest group of animals?
insects
What animals are Hexapods?
Insects
Are insects primarily aquatic or terrestrial?
terrestrial
How many legs do insects have?
6
How many body regions do insects have?
3
What are the 3 regions of insects?
head, thorax, and abdomen
What makes up the head of an insect?
pair of antennae and modified mouthparts
What makes up the thorax of an insect?
has 3 segments, each with a pair of legs; may have 1 or 2 pairs of wings
What makes up the abdomen of an insect?
reproductive organs and majority of digestive and respiratiory system
What do many insects undergo?
metamorphosis
What are the two types of metamorphosis?
simple and complete
What is simple metamorphosis?
immature stages similar to adults, have to molt to grow still
What insects undergo simple metamorphosis?
grasshopers
What is complete metamorphosis?
immature larvae are wormlike and require a resting stage to precede into adult form
What is the resting stage of complete metamorphosis called?
pupa or chrysalis
What insects undergo complete metamorphosis?
butterflies
What is the lifecycle of butterflies?
eggs, larva, pupa, adult
What are young grasshoppers called?
nymphs
How many stages of molting do nymphs go through until they are an adult grasshopper?
5
What is incomplete metamorphosis?
same as simple?
What are Echinodermata?
a phylum, an ancient group of marine animals
What are Echinoderms characterized by?
deuterostome development
Do Echinoderms have an exoskeleton or an endoskeleton?
endoskeleton
What is the enoskeleton composed of in echinoderms?
calcium-containing plates (ossicles)
Do Echinoderms have eye spots?
some do
Do Echinoderms have a brain?
no
Do Echinoderms have neurosensory cells?
yes
Do Echinoderms have a nerve net?
yes
What happens to Echinoderms during development?
They undergo a fundamental shift
What symmetry do the larvae stage of Echinoderms have?
bilateral
What symmetry do the adult stage of Echinoderms have?
pentaradial (5 rays)
How is the body structure of Echinoderms orientated?
in reference to their mouth
What is the epidermis of Echinoderms composed of?
movable or fixed calcium-rich (calcite) plates called ossicles
What is in the epidermis of Echinoderms?
perforated by pores
Why are there pores on the epidermis of Echinoderms?
to allow for extension of tube feet
What do Echinoderms use to move?
water-vascular system
What is the water-vascular system?
a hydraulic system that aids in movement and feeding
What is the water-vascular system composed of?
a central ring from which 5 radial canals extend into each of the body’s 5 parts
What is the opening for water entry of Echinoderms called?
Madreporite
What is the muscular sac for tube feet control called in Echinoderms?
ampulla
What connects toe madreporite to the ring canal?
stone canal
What is the function of tube feet?
allow the animal to move
How do Echinoderms reproduce?
sexually and asexually
How do Echinoderms asexually reproduce?
splitting, broken parts can regenerate the whole animal if there is enough central part
Are Echinoderms hermaphroditic or dioecious?
dioecious
What are the 5 main classes of Echinoderms?
- sea stars and sea daisies
- sea lilies and feather stars (crinoids)
- sea urchins and sand dollars
- sea cucumbers
- brittle stars
What clade are Echinoderms part of?
Deuterostomes
What symmetry do deuterostomes have?
bilateral (at some point in their life)
What body cavity do Deuterostomes have?
true coelomic body cavity
Are Deuterostomes monoblastic, diploblastic, or triploblastic?
triploblastic
What side of an Echinoderm is the oral surface on?
ventral
What side of an Echinoderm is the aboral surface on?
dorsal
How do Echinoderms feed?
some predators, filter feeders, scavengers, deposit feeders
What do Echinoderms feed on?
other invertebrates
Do some Echinoderms actively search for prey?
yes
