Bio II Unit 3 - Invertebrate Adaptation to Land

Eumetazoa

"Eu"= true true tissues

when did exoskeletons first form?

550mya

lophophore (and what it indicates about lophotrochozoans)

A crown of ciliated tentacles that surround the mouth....function in feeding for some, and they may require water, or are aquatic, or live near water

Gene Duplication and Speciation....how are they related

Gene duplication results in rapid speciation

spermatophores

Packets of sperm delivered by the male via special structures, a form of internal fertilization that is indirect

What is responsible for the unique body plan of the insect?

Ubx gene mutation.....it suppressed leg development in the abdomen region of arthropods.....caused by a gene duplication event 400mya

tracheae

air filled tubes that branch through all tissues of an insect's body, motion of the animal increases airflow through the spiracles on the outside of the body

excretion, ammonia

aquatic mammals excrete this because it is highly toxic and is diluted by the water quickly

name some animals in the bilateral ecdysozoa

arthropoda, Tardigrada, onychophora, and nematoda,

parthenogenesis

asexual reproduction, still diploid organism, clonal, new organism from unfertilized eggs...aphids, bees, spiders (ABCs)

arthropoda features and characteristics

bilateral symmetry head, thorax, abdomen (or a cephalothorax) hinge joints chitinous exoskeleton open circulatory system gills, tracheal tubes, or book lungs ventral nerve cord and brain Dioecious, metamorphosis, and sometimes parthenogenesis

characteristics of lophotrochozoans

bilateral symmety and sometime during lifetime they have the presence of a lophophore

myriapoda #DidLandFirst

centipedes milipedes first to colonize land...~450mya...they have tracks of myriapoda animals that were huge!

Bilateria

clade to which most animal phyla belong

copulation

direct internal fertilization..think sexual intercourse

external fertilization in arthropods

eggs are fertilized outside the body

ovoviviparity

eggs are fertilized, stored, and hatch internally, making it seem like live birth happens

internal fertilization

eggs fertilized inside the body

platyhelminthes

flatworms

internal gills

found in aquatic animals like crustacea, fanned quickly, with gas exchange all along the gills

hexapoda

insects EXTREMELY DIVERSE

oviparous

lay eggs

Name some difficulties for invertebrates in their evolution onto land...

less buoyancy UV radiation desiccation gas exchange in air versus water chemoreception differentin water vs air

genitalia in insects

like a lock and key....highly specialized...leads to speciation in short amounts of time

custacea

lobbies!!! pill bugs plankton crabs

nematodes

not segmented, roundworm

spiracle

opening to the tracheae on the outside body of the insect

Name some animals in the Bilateria Lophotrochozoans

platyhelminthes, rotifera, ectoprocta, brachiopoda, mollusca, annelida,

exoskeletons are made of

protein and chitin....it is a modified polysaccharide that contains nitrogen

exoskeletons were helpful in the transfer to land because they...

provide a very tough protection and defense, UV protection, toleration to desiccation, easily adaptable into pinchers, fangs, etc.

book lungs

saclike pockets with highly folded walls for respiration, in chelicerata

why are arthropods so damn successful?

segmented body alllows for quick/easy evolutionary change to selection pressures

annelida

segmented worms

how does the segmented body plan result in diverse forms?

segments can change quickly, based on different selection pressures, and how the hox genes present in the body

characteristics of ecdysozoans

shed an external, tough coat made of chitin, and bilateral

mollusca

snails, clams, squid, octopi

cheliceriformes

spiders, horseshoe crabs, scorpions

porifera

sponges, represent the basal taxon in invertebrates

excretion, uric acid

terrestrial inverts excrete this and it is a little pellet and is the least soluble out of urea and ammonia

onychophora

velvet worms segmented, fleshier

excretion, urea

vertebrates excrete this and it requires a lot of water, and is less soluble than ammonia

tardigrada

water bears can survive in space, extremophile segmented