Ch. 33: Invertebrates Flashcards
1
Q
Sponges have been traditionally considered as the ..
A
Basal animal group
2
Q
Basal animal group, however,
A
recent data suggest that a – bilateral organism is more likely basal and
– Ctenophora has been tentatively placed as the basal animal group
3
Q
Cnidarians are an
A
Ancient phylum of radially symmetrical and diploblastic animals
4
Q
Lophotrochozoans
A
- A clade identified by molecular data
- Have the widest range of animal body forms
5
Q
Ecdysozoans
A
The most species-rich animal group
6
Q
Echinoderms and Chordates are
A
Deuterostomes
7
Q
Porifera
A
- Asymmetric
- Lack Tissues
- Cellular-level of organization
- Needs: O2, nutrients (in) and CO2, waste (out)
- Porocytes: form tube that water can go through
- Choanocytes: currents …
- Pinacocytes (epidermis): epidermal cells
- Amoebocytes
- Meshyl
- Thin wall around open space (3 levels)
- Low metabolic rate
- High SA/V
- Main ∆c = bulk flow
- Sessile organisms
- Crypsis
8
Q
Porocytes
A
form tube that water can go through
9
Q
Choanocytes
A
currents ??
10
Q
Pinacocytes
A
in epidermis
- Epidermal cells
11
Q
Amoebocytes
A
d
12
Q
Sessile Organisms
A
Gemule
13
Q
Gemule
A
if freshwater, can form spore-like structures that could …
- some land on hermit crabs
14
Q
Crypsis
A
the ability of an animal to avoid observation or detection by other animals
- i.e. camouflage
15
Q
Crypsis
A
the ability of an animal to avoid observation or detection by other animals
- i.e. camouflage
16
Q
Cnidaria
A
- named after cnidocytes
- Diploblastic, tissue level
- Radial Symmetry
- Nerve Net (only “system”)
- Myoepithelial (muscle)
- Epidermis (Ectoderm)
- Gastrodermis (endoderm)
- Mesoglea (gelatinous substance)
17
Q
Cnidocyte
A
cells with nematocyst
18
Q
Cnidocil
A
sensitive to touch
- mechanoreceptor protein
- can change/ permeability to water
19
Q
2 body forms of Cnidaria
A
1) polyp
2) medusa
- Both have epidermis and gastrodermis (cover gastrovascular cavity)
20
Q
Polyp
A
- tentacles are thicker
- sessile form
21
Q
Medusa
A
d
22
Q
Diverticula
A
medusa
“sac”
23
Q
Nervous system of cnidaria
A
movement
coordinating
spacial ?
24
Q
Metabolic Requirements for Animal Life
A
1) Oxygen (O2) in and CO2 out
2) Nutrients in
3) Waste out => nitrogenous waste (one of three forms: NH3 (ammonia), Urea, Uric Acid
4) Water/Salt balance (osmotic)
5)
25
Metabolic Requirements for Animal Life
1) Oxygen (O2) in and CO2 out
2) Nutrients in
3) Waste out => nitrogenous waste (one of three forms: NH3 (ammonia), Urea, Uric Acid
4) Water/Salt balance (osmotic)
5) Central control of cell/tissue function
=> (neurons) via nervous system via endocrine system
26
Phylum Ctenophors (comb jelly)
- named after ctene (comb)
- "Comb" rows of cilia used for locomotion
- Radial symmetry
- Diploblastic
- Epidermis
- Mesoglea
- Gastrodermis
- GVC (gastrovascular cavity)
- No cnidocyte; yes to colloblast (sticky (ensnare prey)
- complete digestive system
- Large SA/V ; Fiele's Law
27
Bilartaria
- Bilateral Symmetry
- Cephalization (making a head)
=> concentration of sensory organs/nerves at one end
28
Lophotrochozoa (2 groups)
1) Lophophorates
2) Trochozoa
- lophophore: feeding structure
- trochophore larvae
- animal
29
Ecdysozoa
- ecdysis: mold/shed cuticles (thick part of epidermis/ exoskeleton)
- animal
30
Platyhelminthes
flatworms
- dorsal-ventral flattening
- Can be free-living or parasitic
- Bilateral
- Triploblastic (3 layers)
- Acoelomate
- can be parasitic (Tapeworm and flukes) or free-living (Planaria/Dugesia)
31
Triploblastic layers of Platyhelminthes
- ectoderm: epidermis/nerve
- Mesoderm: parenchyma (C.T., muscle)
- Endoderm: gut
32
Dioecious
separate sexes
33
Monoecious
hermaphroditic
| self-fertilization
34
Trematoda
Flukes: 2 types
1) Clonorchis sinensis (Chinese liver fluke): human and two intermediate hosts
2) Schistosomes: "blood fluke"
infection: schistosomiasis/
live in veins/ burrow in human skin
35
Clonorchis sinensis life cycle
- eggs go into snail
- go into fish muscle
- humans eat fish
- lives in gull bladder or bile duct
- dominate host: human
- intermediate host: snail, fish
36
Schistosomes life cycle
- burrow into human skin
- ciliated larva go into snail
- motile larva will burrow into human skin
- dominate host: human
- intermediate host: snail
37
Planaria can be cut
- up to 10 transverse cuts = 10 planar
- cut closer to head => faster regeneration
- the orientation of actin cytoskeleton can effect rate/type of regeneration
38
Phylum Rotifera
- pseudocoelomate
- complete digestive tract
- wheel-animals
- primarily freshwater but some marine
- rarely see males
- have toes: suspension feeders
39
Corona
- wheel organ found in the Phylum Rotifera
- jaws (mastea): structure can close
- Circulatory crelonic fluid
- Pedal glands
40
Rotifera reproduce
through parthenogenesis: development of unfertilized egg (haploid)
41
Lophophore vs Trochophore
Lophophore:
- U-shaped tentacle
- Feeding apparatus
- All marine
- i.e. ectoprocts (sea mat) branchpods
```
Trochophore:
- Ciliated larvae w/ complete digestive system
- Ciliated:
=> apical tuft
=> equatorial band
=> Complete digestive system
=> Respiratory/circulatory organs
```
42
Phylum Mollusca
- adaptive radiation into a variety of riches
- larger
- more complex, more systems
- Tripartite body plan: mantle, visceral mass, foot
43
Tripartite body plan of Mollusca
- Mantle: may secrete a shell (always have)
- Visceral Mass: organs and coelom and hemocoelom
- Foot (muscular): heart and kidneys (nephridium), gonads
44
Mollusca hemocoel
- hemolymph: a fluid filled cavity
| - suspended within a gastrointestinal tract
45
Mollusca Mantle Cavity
air space (acts as simple lung)
or gills present (aquatic sp)
46
Mollusca Cardiovascular System
Open: hemolymph is not contained in vessels at all times
organs bathed in hemolymph directly
47
Mollusca digestive system
Complete
- Mouth: radula: stiff-ribbon-like appendage with chitin => scraping
- Pharynx => stomach <=> digestive glands (pyloric ceca) acts like both a liver and pancreas and absorptive organ
stomach => intestine => anus
48
Mollusca Respiratory
"lung" (simple) = mantle cavity
gills
49
Mollusca Nervous System
- Circumpharyngeal ganglion ("brain")
- Ventral nerve cords
- Other smaller ganglia in visceral mass
50
Class Gastropod
Phylum Mollusca
- have torsion
- visceral mass turns
51
Class Bivalvia
Phylum Mollusca
| - Ctenidia: ciliated; capture food/ respiratory/ gills
52
Class Cephalopoda
Phylum Mollusca
- body plan modified for locomotion/feeding
- Closed circulatory system
- Great Vision
- i.e. Nautilus: can add/lose air
- Octopus/Squid: can change color for different reasons
- > Octopus: based on moods/ communication
- > Squid: mating, terrestrial (cuttlefish)
53
Phylum Annelida
- coelomates with metamerism
54
Metamerism
a serial (repetition) row of similar body parts along the length of an animal
55
Coelomate
Septa divide coelom into compartments associated with block of muscle
56
why a metamerism
- great increase in muscle coordination
- increase types of actions possible
- adaptive radiation
57
Nervous system of Phylum Annelida
- circumpharyngeal ganglion
- 2 ventral nerve cords
- each metamere is independently controlled by transverse nerves
- tactile, chemosensory
58
Annelida Coelom
1) independently move body wall and gut
2) expansion of space for gonads and larger and more types of organs
3) (serves as a) hydrostatic skeleton (very important)
59
Annelida Circulatory system
- closed
- no heart, but pulsatile arteries
- Coelomic fluid: medium for diffusion to and from circularity vessels
- Hemolymph: contains some hemoglobin/ a respiratory pigment/ increase total [O2] in hemolymph
=> O2 soluble and O2 bound to pigment
