Chapter 3.2.4 Kingdom Animalia Part 1 & 2 Flashcards
describe the two types of symmetry
radial symmetry
- top and bottom
- no front and back
- no left or right
bilateral symmetry
- top (dorsal) and bottom (ventral)
- front (anterior) and back (posterior)
- left and right side
what is cephalization in bilateral animals
evolutionary trend toward concentration of sensory equipment at anterior end of body (the head)
if an animal is sessile (live attached to substrate) or planktonic (drifting, weakly swimming), what type of symmetry fits its lifestyle
radial symmetry
- can meet environment equally from all sides
if an animal move more and with direction, what type of symmetry fits its lifestyle
bilateral symmetry
what differentiates ectoderm and endoderm
ectoderm
- germ layer covering surface of embryo
- outer covering of animal and sometimes central nervous system
endoderm
- innermost germ layer
- lines archenteron
- produces lining of digestive tract/cavity
what does diploblastic mean
- animals with only ectoderm and endoderm
what does triploblastic mean
- animals with 3 germs layers, mesoderm between ectoderm and endoderm
what is the function of mesoderm
- forms muscles and organs between digestive tract and outer covering
what is the name of the body cavity that most triploblastic animals have
coelom
- fluid or air filled space between digestive tract and outer body wall
what do we call animals with true coelom completely lined with mesoderm
coelomates
what do we call animals with a body cavity formed from mesoderm and endoderm
pseudocoelomates
what do we call animals with no body cavity
acoelomates
what are the 3 main functions of body cavitites
- fluid cushions suspended organs
- fluid may act as a skeleton
- allows internal organs to grow and act independently
difference in cleavage between protostome and deuterostome development
protostomes
1. cleavage
- display spiral, determinate (programmed to be a specific part) cleavage
deuterostomes
- display radial, indeterminate (not programmed to be anything specific) cleavage
difference in coelom formation between protostome and deuterostome development
protostomes
- solid masses of cells split to form body cavity/coelom
deuterostomes
- buds from wall of archenteron and cavity becomes coelom
difference in the fate of blastopore between protostomes and deuterostomes
protostomes
- mouth develops from blastopore
deuterostomes
- anus forms from blastopore
main characteristics of porifera sponges
- asymmetrical or radially symmetrical
- no true tissues
- most are marine
- sedentary
how does suspension feeding works
- captured food particles are suspended in water and pass through their body
- water enters spongocoel
- water flows out of osculum
what are the different types of cells in sponges
- Choanocytes, line spongocoel
- Amoebocytes: intra cellular digestion
most are hermaphroditic
what are the cnidaria
- hydras, jellyfish, corals
- radial symmetry
- diploblastic
what is the body plan of cnidaria
sac with gastrovascular cavity
- one opening to cavity (incomplete digestion (doesn’t have 2 holes))
- simple nervous system
what are the two major body forms of cnidaria and their characteristics
Polyp
- extend tentacles and wait for prey
- mouth up
- adhere to substrate (any surface) with aboral end (bottom end)
Medusa
- tentacles dangle from oral surface
- moves passively or contracts body
- mouth down
true of false some cnidaria can have both polyp and medusa body forms in their life cycle
true
what are the uses of tentacles
- to capture prey
- direct food toward opening of gastrovascular cavity
- defense
what are cnidocytes
specialized cells with nematocyst
- organelle housing stinging thread
- can be discharged and explode outward
- puncture or inject poison
main characteristics of platyhelminthes
- bilateral symmetry
- triploblastic
- acoelomates
- damp environments
- free living parasitic groups
what explains the flattened shape of platyhelminthes
- all their cells are close to water (environment)
- allows gas exchange and elimination of waste by diffusion across body surface
(flat shape maximizes surface area for efficient exchange) - gastrovascular cavity, in flat body food doesn’t have to travel a lot, it branches to animal’s cells
true or false playhelminthes does complete digestion
false, incomplete
gastrovascular cavity with one opening
what are the three main groups of platyhelminthes
- planarians
- flukes
- tapeworms
characteristics or planarians
- free living
- eyespots
- simple nervous system
characteristics of flukes
- parasitic
- require different hosts for different life cycle
- alternating sexual and asexual stages
main characteristics of tapeworms
- parasitic inside vertebrates
- no mouth or gastrovascular cavity, absorb nutrients across body wall
- have scolex (suckers for attachment)
how do tapeworms reproduce
sections called proglottids (reproductive structures) detach from parent and leaves host
characteristics of nematoda
roundworms
- bilateral symmetry
- triploblastic
- pseudocoelomates
- protostomes
- complete digestive tract
- no circulatory system
main characteristics of annelids
segmented worms
- bilateral symmetry
- triploblastic coelomates
- protostomes
- complete digestive system
- damp environment
digestion in annelids
crop
- stores food
gizzard
- grinds food
intestine
- digestion and absorption
does annalids have a close or open circulatory system
closed
- dorsal vessel above digestive tube
what is interstitial fluid called in an open circulatory system
hemolymph
how does annelids separate their interstitial fluid and their blood
with their close circulatory system
what are mollusks and their main info
- Bilateral symmetric
- Triploblastic
- True coelomates
- Protostome
- Have a complete digestive tract (gut)
- Soft bodied (secrete calcium carbonate for shell)