Mollusks - How the nervous system works Flashcards
(91 cards)
1
Q
how many species of Mollusca are there?
A
more than 100,000
2
Q
Mollusca is the ____ largest animal group after arthropods
A
2nd
3
Q
How are Mollusca diverse?
A
they are diverse in their
- morphology
- modes of nutrition
- reproduction
- response to environment
4
Q
how are Mollusca symmetrical?
A
bilaterally
5
Q
Mollusca are ___plastic
A
triploblastic
6
Q
what are the four major groups of Mollusca
A
- polyplacophora
- gastropoda
- bivalvia
- cephalopoda
7
Q
what does the mantle cavity of Mollusca contain?
A
gills
8
Q
For land living organisms the mantle cavity is …
A
an extended space for surface oxygen exchange
9
Q
The front end of the intestine is known as the
A
radula
10
Q
the Polyplacophora is known as the
A
“bearer of many plates”
11
Q
how many overlapping plates does the Polyplacophora have?
A
eight!
12
Q
Polyplacophora are…
A
omnivorous
13
Q
where are the gills located in Polyplacophora
A
in the mantle grooves?
14
Q
Polyplacophora are able to withstand ___ ____
A
low oxygen
15
Q
Bivalvia means …
A
“two valves”
16
Q
Bivalvia have a reduction of
A
head
17
Q
the mantle cavity of Bivalvia is modified by
A
siphons
18
Q
how do Bivalvia get oxygen?
A
by using their gills
19
Q
what else do the gills of Bivalvia do?
A
filter food
20
Q
are Bivalvia sessile or mobile?
A
sessile
21
Q
what kind of feeders are Bivalvia
A
filter feeders
22
Q
Siphons are extensions of
A
posterior mantle
23
Q
In Siphons water flows in the __ ___ and then across the ___ that act as ___ for food
A
mantle cavity ; gills ; filters
24
Q
there are two exits/entries in Siphons
A
one water is sucked in and the other water is squished out
25
what is the most diverse group of mollusks?
Gastropoda
26
how many species of Gastropoda are there?
85,000
27
what kind of eaters are Gastropoda?
herbivores, predators, scavengers
28
what kind of fertlization do Gastropoda do?
both internal and external
29
Gastropoda are either _______ or hermaphroditic but can produce only sperm or eggs at any given time
dioecious
30
Dioecious means
separate sexes
31
Gastropoda means
stomach foot
32
how do Gastropoda move?
torsion of the body
33
where is the anus of a Gastropoda
over the head!
34
a species of Gastropoda are
land snails
35
where are the eyes located on Gastropoda?
on the tentacles
36
what is the radula modified into in cone snails?
into toxic harpoons
37
cone sails are also known as
cigarette snails because if you're stung by one, the only time left tat you have is for one cigarette
38
nidubranchs means
naked gill
39
aposematic says
don't touch me! I'm toxic!
40
How do Gastropoda reproduce?
love darts
| - mutual exchange of sperm
41
Cephalopoda have an enlarged _____ and a reduced ____
head ; shell
42
what do Cephalopoda use their mantle and siphon for?
jet propulstion
43
Cephalopoda use this to shoot ink out of the mantle cavity and use this fore to push predators away
Siphon
44
Cephalopoda have visual communication with
colour and texture
45
what do Cephalopodas use as their defense?
ink sac
46
what kind of circulatory system do Cephalopoda have?
closed.
47
some Cephalopoda use their tentacles to transfer
sperm
48
how do Cephalopoda reproduce?
separate sexes with elaborate courtship
49
what kind of fertlization do Cephalopoda do?
internal
50
how do male Cephalopoda transfer sperm?
via a specialized arm called the hectocotylus
51
what happens to female Cephalopoda after they lay/hatch their effs
they die
52
what does the reproduction cycle of Cephalopoda NOT have?
Trochophore larva
53
how many arms do Nautilus?
80-90 arms
54
how do Nautilus regulate its buoyancy?
with gases in chambered shell
55
Nautilus are the only extant ____ chephalopod
shelled
56
when did Ammonite go extinct?
at the end of the creatceous period
57
Mollusks are ___ for parasites
vectors
58
the giant squid can reach up to
15 m long
59
giant squid are large enough to support intracellular recording by the first
microelectrode
60
what is the function of the nervous system?
to produce behaviour
61
what tasks does the nervous system perform?
detection and analysis of sensory signals
62
what tasks does the nervous system perform?
decision making
63
what tasks does the nervous system perform?
generation of coordinated motor output
64
what tasks does the nervous system perform?
disregard non-important information
65
the nervous system also generates...
mental activity
66
Dendrites
receive information from other neurons via synapses
67
cell body (soma)
contains nucleus and most cell organelles
68
what integrates info collected by dendrities and initates action potentials?
axon hillock
69
what is known as the "telephone line of nerve cell" that synapses at terminal to target cell
axon
70
what are glia cells?
electrical insulation of nerve cells
71
what do Neurons generate and transmit?
electrical signals
72
what do glial cells provide?
nutrients that maintain extracellular environemt
73
glial cells are part of the
blood-brain barrier
74
glial cells fight...
infections of the nervous system
75
how do neurons work?
ELECTROCHEMICALLY
76
what does ELECTRO mean?
difference in charge across the cell membrane
77
what does CHEMICAL mean?
concentration gradients of ions across cell membrane
78
what prevents the free movement of ions?
lipid bilayer
79
what controls the ion flux across the membrane?
ion channels and ion transporter proteins
80
what determines the membrane potential?
the interaction of two forces
81
what does diffusion favour?
it favours the net movement of ions down their concentration gradient
82
this force favours net movement of ions according to potential difference
electromagnetic force
83
when the two forces are balanced for a GIVEN ION this is called
equilibrium potential
84
Depolarization
Na+ channels open
85
when does depolarization become regenerative?
if the tresh-hold level of depolarization reaches around -50 mV
86
when Na+ channels close while voltage-gated K+ channels open this is called
repolarization
87
How are concentration gradients of ions maintained in the long run?
by ACTIVE processes
88
what does Na+/K+ pump require?
ATP
89
Brief "spikes" of membrane potentail from resting potential towards equilibrium potential of Na+ are called
action potentials
90
Graded potentials
strength and temporal pattern of input determines mebrane potential; potential decays with distance along nerve fiber; only works over short distances
91
how is information encoded in electrical activity or nerve cells and populations of nerve cells?
nerual code
