week 8b Flashcards
(32 cards)
where is the nervous system located in protostomes
on the ventral side of the body
where is the nervous system located in deuterostomes
on the dorsal side of the body
in protosomes, what does the brain surround
the opening of the digestive tract
what is a body segment
a repeated body structure along the anterior-posterior axis with its own polarity
3 examples of animals with segmented bodies
annelid worms, lobsters and chordates
what is segementation commonly associated with
movement
what morphological traits were traditionally used to classify animals
presence/absence of a coelom and body segementation
why are morphological traits now considered unrealiable for evolutionary relationships
molecular data shows they do not accurately reflect evolutionary history
what molecular methods are used to classify animals today
comparions of DNA, RNA and amino acids sequences
what do fewer molecular differences between 2 species suggest
a closer evolutionary relationship
what are the 6 major animal groups in chapter 34
- ctenophores
2.profera - radiata
- lophotrochozoa
- ecdysozoa
- deuterostomia
what % of animals are invertebrates
95%+
what are ctenophores commonly known as
comb jellies
how do ctenophores move
using 8 rows of cilia on their surface
what do ctenophores use to catch prey
2 sticky tentacles
what is unique about ctenophores digestive systems
they have the first complete gut with mouth, gastrovascular cavity, and 2 anal pores
are ctenophores hermaphroditic or separate sexes
hermaphroditic
are ctenophores bioluminescent
yes
what does porifera mean
pore bearers
do sponges have true tissues
no they lack true tissues
are sponges symmetrical
no they have no apparent symmetry
how adult sponges differ from larvae
adults are sessile, larvae are free-swimming
approx. how many species of sponges exist
~8k mostly marine
what type of data was traditionally used to classify animals
morphological traits like body cavities and segmentation
