Chapter 19: Phylum Arthropoda, Subphylum: Crustacean Flashcards
1
Q
Probably the most abundant animals in the world are members of the copepod genus ___.
A
Calanus
2
Q
What is a main distinguishing characteristic of Crustaceans?
A
- two pairs of antennae
3
Q
Their head has a pair of ___ and two pairs of ___.
A
- mandible, maxillae
4
Q
There is one pair of ____ on each of the additional segments. Some segments may lack ___. All appendages, except perhaps the first antennae are all _____.
A
- appendages, appendages
- biramous
5
Q
What does biramous mean?
A
-limbs branch into two, and each branch consists of a series of segments attached end-to-end.
6
Q
Primitive crustaceans may have up to __ segments, derived crustaceans tend to have ___.
A
- 60
- fewer
7
Q
Tagmata are usually __, ___ and __. They are not ___ across taxa.
A
- thoracic, thorax and abdomen
- homologous
8
Q
In most one or more thoracic segments are ___ with the head asa __.
A
- fused
- cephalothorax
9
Q
Arrangement of tagmata in Malcostraca is the ancestral plan meaning what?
A
- head has five fused somites
- thorax has eight
- abdomen has six
10
Q
The anterior end is a non-segmented ___.
A
Rostrum
11
Q
What forms the tail?
A
- telson (posterior most division of an arthropod) , last abdominal somite, uropods
12
Q
The dorsal covering is called what?Which may cover how much of the body ?
A
- carapace
- most of the body or just the cephalothorax
13
Q
The secreted cuticle is made of what? (3)
A
- chitin, protein, calcareous deposits
14
Q
The joints are soft and thin allowing what?
A
- flexibility
15
Q
Some crustaceans have appendages on each ___, others may not bear appendages on abdominal __.
A
- somites, somites
16
Q
Somite specialization is based on what basic plan?
A
- biramous plan
17
Q
Appendages represent serial ____. They have evolved a wide variety of ___, ___, __ etc from modification of the basic ___ appendage.
A
- walking legs
- mouth parts
- swimmerets
- biramous
18
Q
Muscular and nervous systems and segmentation exhibit ___ of annelid like ancestors.
A
- metamerism
19
Q
They have a hemocoel. What does this mean for it’s body cavity?(3)
A
- Persistent blastocoel that becomes filled with blood
- coelomic compartments remain as end sacs of excretory organs and gonads
- coelomates only in technical sense of the term.
20
Q
What kind of muscles make up a major portion of the crustacean body.
A
- striated muscles
21
Q
Most muscles are arranged as ____ groups. ___ draw a limb toward the body and ___ straighten out the limb.
A
- antagonistic groups
- flexors
- extensors
22
Q
What muscles of the crayfish allow them to swim backwards?
A
- abdominal flexors
23
Q
What’s the location of the strong muscles that control the mandibles of a crustacean?
A
- each side of the stomach
24
Q
Smaller crustaceans may exchange gasses how?
A
- across thinner areas of cuticle
25
How do larger crustaceans exchange gasses?
- featherlike gills
26
What overlaps the gill cavity leaving anterior and posterior openings?
- Decapod carapace
27
What part of the second maxilla draws water over gill filaments?
- Bailer
28
Gills may project from ___, the articulation of ___ or ___.
- pleural wall, thoracic legs, or thoracic coxae
29
What kind of circulatory system do they possess?
- open circulatory system
30
They do not have a system of ___ to separate blood from ___.
- veins
| - interstitial fluid
31
What exits the heart via arteries?
- hemolymph
32
Hemolymph passes to the ___ to return to the heart via ___.
- hemocoel
| - sinuses
33
They possess a __ aorta. Which is a __ chambered sac of __ muscle.
- dorsal
- single
- striated
34
Valves in the arteries prevent what?
- back flow of hemolymph
35
Hemolymph is conducted to ___, if present for __ and ___ exchange.
- gills
- oxygen
- carbon dioxide
36
In terms of colour hemolymph may be ___ or, ___, ___. It contains ___ that help prevent clotting .
- colourless, reddish, bluish
| - ameboid cells
37
Hemocyanin and or hemoglobin are ______.
- respiratory pigments
38
Antennal or maxillary glands also called green glands in decapods do what for crustaceans? What do they consist of?
- function in excretion of wastes
| - end sac, labyrinth, tubule and a bladder which leads to the outside
39
Hydrostatic pressure within a hemocoel provides a force for ___ of fluid into the ___ of the excretory glands.
- filtration
| - end sac
40
Resorption of salts and amino acids occurs as the filtrate passes through the ___ and ___. Which mainly regulates the __ and __ composition of body fluids.
- excretory tubule, bladder
| - ionic, osmotic
41
Freshwater crustaceans are constantly threatened by what? What must the gills do ?
over dilution with water
| - gills must actively absorb Na + and Cl-
42
Marine crustaceans have urine that is ____ with blood.
- isosmotic ( having the same osmotic pressure)
43
What is excreted across thin areas of cuticle in the gills?
- Nitrogenous wastes
44
Crustaceans have more fused ___ than any other arthropod.
ganglia
45
A pair of _____ connects to eyes and two pairs of antennae.
- supra-esophageal ganglia
46
____ join the supra-esophageal ganglia to the ____. It supplies nerves to the ___, ___, ___ and ___.
- neuron connectives
- subesophageal ganglia
- mouth, appendages, esophagus and antennal glands.
47
They possess a ___ nerve cord which has a pair of __ for each somite to control appendages.
- double ventral nerve cord
| - ganglia
48
What are the largest sensory organs in crustaceans?
- eyes and statocysts.
49
Tactile hairs occur n the body, especially on __, __ and ___.
- chelae (pincerlike claw)
- mouthparts
- telson
50
Chemical sensing of taste and smell occurs where?
- in hairs on antennae and mouth
51
Statocyst opens at the base of the ____ in crayfish. The statocyst is lined with ___ which detect the position of grains of sand.
- first antenna
| - sensory hairs
52
Compound eyes are made up of many units called what?
- Ommatidia
53
Compound eyes:
- What does the cornea do?
- What forms a sleeve around each ommatidium
- Each ommatidium detects what?
- In dim light the distal and proximal pigments do what?
- focuses light down the columnar ommatidium
- distal retinal, proximal retinal, and reflecting cells
- detects a restricted area of objects, a mosaic, in bright light
- separate and produce a continuous image
54
Most crustaceans brood (incubation) eggs in ____, in ___ attached to the ___ or attached to ___.
- brood chambers
- brood sacs
- abdomen
- abdominal appendage's
55
Most crustaceans have a larva ___ the adult in form, and undergo ____.
- unlike
| - metamorphosis
56
The ___ is a common larval form with a uniramous ____ and ___ that aid id in swimming. What are added via a series of molts?
- Nauplius
- first antennae
- mandibles
- appendages
57
What is necessary for crustaceans to go through in order to increase in size since ___ does not grow?
- Ecdysos ( molting)
| - exoskeleton
58
The physiology of molting affects what three things?(3)
- reproduction, behaviour and many metabolic processes.
59
What secretes the cuticle?
- underlying epidermis
60
What is the outermost epicuticle made of?
- very thin lipid impregnated protein
61
Most of the cuticle is composed of several layers of?
- procuticle
62
The exocuticle, beneath the epicuticle, contains what three things?
- protein, calcium salts and chitin
63
The endocuticle has a heavily calcified ___ layer and an uncalcified ___ layer.
- principle
| - membranous
64
Molting animals how in what phase of molting?
- intermolt phases or instars
65
Soft tissue ___ in size until there is ___space within the cuticle.
- increases
| - no
66
When the body fills with cuticle what phase is the animal in before molting occurs.
- premolt phase
67
Before molting occurs ___ enlarge.
- epidermal cells
68
During the molting process Crustaceans secrete a new ___ and then begin secreting a new ___.
- epicuticle
| - exocuticle
69
What are released into the area above the new epicuticle that dissolves the old endocuticle?
- enzymes
70
When only the old exocuticle and epicuticle remain the animal does what to expand and burst the old cuticle?
swallows water
71
After the old cuticle is shed , softs new cuticle stretches and then hardens with the deposition of what?
- inorganic salts
72
Molting often occurs in ___ and may cease in ___.
- young animals
| - old animals
73
Hormonal control of Ecdysis :
- What can trigger the central nervous system to to begin ecdysis?
- The central nervous system will decrease the molt inhibiting hormone which is produced by the __.
- While promoting release of molting hormone from the ___ which promotes ecdysis.
- temperature, day length, or other stimuli
- x-organ
- y-organ
74
Removing what will accelerate molting and prevent colour changes to match the background.
- eyestalks
75
Hormones from neurosecretory cells in the eyestalk control dispersal of ___.
- cell pigment
76
Neurosecretions from ____ stimulate increase in heartbeat.
- pericardial organs
77
Suspension feeders generate _____ in order to feed on plankton, detritus, and bacteria.
- water currents
78
Predators consume what?(5)
- larvae, worms, crustaceans, snails and fishes
79
Scavengers eat ___ and ___.
- dead animals and plant matter
80
Crayfishes have a ___ stomach. Gastric mill grind up food in the ____.
- two part stomach
| - first compartment.
81
Phylogeny and Adaptive diversification?
- Crustaceans re unquestionably the ___ arthropod in marine environments.
- They ale share dominance in ___ with insects
- The class Malacostraca is the most ___ and members of ___ are the most abundant.
- Copepods are particularly successful as ___ of both __ and __.
- dominant
- fresh water environments
- abundant
- Copepoda
- parasites, vertebrates, invertebrates
