Zoology Flashcards
(192 cards)
1
Q
What is an animal?
A
-an eukaryote organism
-heterotrophic (consume organic matter)
-able to move
-reproduce sexually
-develop from a blastula (hollow ball of cells that forms during the early stages of animal embryonic development)
(will be some exceptions)
2
Q
when did eukaryotes arrise?
A
about 2000 million years ago
3
Q
what is a eukaryote?
A
An organism that have a cell nucleus enclosed within a membrane. These include green plants, fungi and animals ect.
4
Q
what is the Opisthokonta domain
A
A eukaryotic Domain,
-single posterior flagellum,
- extracellular digestion (derive energy from outside their cells)
e.g fungi and animals.
5
Q
what domain are animals apart of?
A
Opisthokonta domain.
6
Q
what is a metazoan organisms?
A
Animals.
-multicellular
- differentiated tissues specialised for functions.
7
Q
What does heterotropic mean?
A
consume organic matter
8
Q
What characteristics do animals have?
A
-heterotrophic
-consume oxygen
-can move
-normally sexually reproduce
-develop from a blastula
(there are some exceptions)
9
Q
what is the one group that arn’t animals from the Opisthokonta domain?
A
choanoflagellata (metazoans but not animals)
10
Q
What 2 groups can the Animalia be split into?
A
The Porifera (sponges) and Eumetazoa.
11
Q
The Bilateria can be divided into what 2 sub groups?
A
Deutrostomia and Protostomia
12
Q
What 2 groups can the Protostomia be divided into?
A
Ecdysozoa and Spiralia
13
Q
Give an overview of the Choanoflagellata…
A
-metazoans
-unicellular eukaryotes (not animals)
-flagellates
-can be free living/colonial
-funnel shaped collar
-sexual/asexual reproduction
14
Q
What is the “ur metazoan”?
A
Hypothetical last common ancestor of all animals.
-first multicellular animal
-eukaryotic
-flagellate
-marine
-two cell layers (diploblastic)
-no symmetry
15
Q
Describe characteristics we think the “ur metazoan” has…
A
-eukaryote
-flagellate
-marine
-2 cell layers
-no symmetry
16
Q
What orders are found within the basal metazoans?
A
-porifera
-cnidaria
-ctenophora
-pacozoa
They are the first metazoans that originated. All metazoans that are not bilateral.
17
Q
Animalia can be split up into Poerifera and Eumetazoa, but we can also divide them into paraphyletic groups…
A
-Basal Metazoans (paraphyletic group)
-Bilateria (monophyletic)
18
Q
What are the characteristics of the Basal Metazoans?
A
-asymmetrical/radially symmetrical (anything but bilateral)
-two layers of cells ( interior/exterior)
-no organs but some differentiation of tissues
19
Q
What does it mean to be radially symmetrical?
A
Symmetrical arrangement of body parts around a central axis.
20
Q
What are the key features of the Bilateria?
A
- Bilateral (have 3 major axis…left/right, dorsal/ventral and anterior/posterior)
-triploblastic
-complete digestive track (separate mouth and anus)
21
Q
What does it mean to be Triploblastic?
A
three layers of cells, with a coelom (fluid filled cavity)
22
Q
what does dorsal and ventral refer to?
A
Dorsal= top of the body
Ventral= bottom of the body
23
Q
what does anterior and posterior mean?
A
Anterior=front of the body
Posterior= back of the body
24
Q
Key features of the Porifera?
A
-it’s a Basal Metazoan ( Diploblastic, no organs hence no digestive/circulatory or nervous systems)
-sponges
-no symmetry
-ancient lineage
25
How do the Porifera respire and feed?
-Aquiferous system.
-Sponges have ostia bringing water in and across their choanoderm (interior surface) by choanocyte flagella.
-Water flows across cells responsible for food gathering/ respiration.
-Waste products leave through Osculum.
26
How do the Porifera reproduce?
Sponges can be sexual/asexual.
-Sexual; -hermaphrodites
-sperm/eggs produced by the
choanocytes cells and released via
Aquiferous system.
-can be oviparous/ viviparous
-Asexual; fragmentation
-budding (colonial)
-asexual larvae
27
What are oviparous species?
egg laying species
28
What are viviparous species?
release larval forms directly
29
what phylum does Calcarea fall into?
Porifera
30
Describe Calcarea sponges...
-interior skeleton made of calcium carbonate
-they have either 1,3 or 4 rayed spicules
31
what phylum does the class Hexactinellida belong to?
Porifera (sponge), overal group is Basal Metazoan.
32
Describe the class Hexactinellida...
-"glass" sponges
-6 rayed silica based spicules
33
what phylum does the class demospongiae belong to?
Porifera (sponges)
34
Describe the Demospongiae...
-make up 95% of sponges
-spicules are silica based but not 6 rayed like Hexactinellida
35
Describe the distribution of the three Poriferia classes...
Calcarea and Demospongiae are found in shallow waters as need a firm substrate.
Hexactinellida found below 200m (unless its too cold)
36
what 3 classes are found in the phylum Porifera?
-Calcarea
-Demospongiae
-Hexactinellida
37
describe the Placozoa...
-belived to be close to the "ur Metazoans"
-simplest structure of all animals
-2 layers of cells
-lower surface engulfs organic detritus
-reproduce via asexual budding
38
what is organic detritus?
particles of organic material from decomposition of plants ect
39
what paraphyletic naming system describes the two phylums Cnidaria and Ctenophora of the Basal Metazoans?
Coelenterates
40
Describe the phylum Ctenophora
-"comb" jellies
-radial symmetry
-2 layers of cells
-unique "colloblast" cell
-swim using cillia
-bioluminecent
41
what is a Colloblast cell?
a unique cell to the phylum Ctenophora (comb jellies).
They're sticky so used to capture prey. can also take sequester (stinging) cells from jelly fish and leave them on surface.
42
Describe the Cnidaria...
-very diverse (corals, jelly fish)
-can be sessile (rooted to a spot), sedentary ( can move), pelagic (move freely in water collum)
-can be biolumnecent, symbiotic (e.g corals with algae)
-always aquatic
43
key characteristics of Cnidaria?
-radially symmetrical (not always)
-diploblastic (2 cell layers)
-possess cnidae
-single body cavity
-no nervous system but nerve cells surround body to form a net
-alternations of generations (asexual followed by sexual phase)
-cilliated planula larve
44
what are the Cnidae
cell unique to the Cnidaria phylum. 3 types;
1.penetrant-venomous needle
2.glutinant- stick to prey
3.volvent- coil around prey
-single use cells. used for feeding and defence.
45
Describe the alternation of generations of some organisms within the phylum Cnidaria...
-polpoid sessile phase; (can reproduce asexually/ or bud of)
-medusoid phase; (jelly fish)free living and repoduce sexually. Dioecious (male and female individuals)
46
What two subphylums does the Cnidaria have?
Medusozoa and Anthozoa
47
what does "ontology recapitulates phylogeny" -Haeckel
the development of the embryo mirrors the successive stages of evolution.
48
what is evolutionary development biology (evo-devo)
changes in the timing and positioning of embryonic development affects the change of the shape of a descendants body compared to its ancestors.
Embryos reflect the cource of evolution, but its more intricate than Haeckles recapitulation theory
This is the theory that we use today instead of recapitulation theory
49
What is the recapitulation theory?
proposes that the developmental stages of an individual organism (ontogeny) reflect the evolutionary history of its species (phylogeny)
50
provide an overview of early cell cleavage...
1. fertilised egg (Oocyte)
2. morula (solid ball of cells)
3. blastula (hollow ball of cells around blastocoel)
4.gastrula (multi layered ball of cells)
51
How does a Oocyte form a Morula?
Formation of morula (solid ball of cells) from a fertilised egg ( Oocyte) happens via cell cleavage. Radial cleavage or spiral cleavage (twist when looking at top).
Morulation.
52
How does a Blastula become a Gastrula?
Gastrulation. Forms the cell layers and the gut. The Blastopore is where it begins to fold up and can either form the mouth, anus or both.
53
Describe the arrangment of a Diploblastic gastrula...
2 layers of cells ( ectoderm and endoderm). Has an internal cavity known as gastrovascular cavity (stomach and respiration). The blastopore becomes the mouth and anus together.
54
Describe the embyology of Protostomes...
Triploblastic. 3 layers ectoderm, endoderm and mesoderm. Internal cavity called Coelom.
Blastopore becomes mouth first and then anus froms later. spiral cleavage.
"proto" first
"stomes" mouth
(mouth formed first)
55
Describe the arrangment of a Triploblastic gastrula...
Spiral cleavage.
Formation of a new layer of cells along with ectoderm and endoderm called mesoderm. Moth forms from blastopore and anus at opposite end. Cavity within called a coelom (cavity).
56
Describe the embyology of Deuterostomes...
Triploblastic. 3 layers of cells, ectoderm, endoderm and mesoderm. Internal cavity known as the coelom. Anus formed from blastopore and then moth formed. Radial cleavage.
"deutero"-second
"stome"-mouth
(mouth formed second)
57
Bilateria have what forms of directionality?
-anterior(front)/posterior(back)
-dorsal(top)/ventral(bottom)
-left/right
58
How many layers of cells do all Bilateria have?
3 layers!
-ectoderm (epidermis and nevers)
-endoderm (digestive track)
-mesoderm (muscles and connective tissues)
59
All Bilateria have a _______ digestive track which means_____.
complete digestive track. which means they have a separate mouth and anus. (all triploblastic)
60
What two groups branch off the Protostomes?
-Ecdysozoa
-Spirallia
61
Where do the ecdysozoa get there name from?
The way that they grow.. ecdysis
(moult their exoskeleton)
62
What key characteristics do Ecdysozoa have?
-grow by ecdysis (moulting their excoskeleton)
-lack locomotory cillia (dont move cillia to move)
-amoeboid sperm (dont have flagella)
-"teeth" within the forgut (basal, to grind up food)
-ring of spines around the mouth (basal,help capture prey)
-spiral cleavage (embryo)
63
Describe the key characteristics of Spiralia...
-spiral cleavage (embryo)
-otherwise defined as protostomes lacking the attributes of the Ecdysozoa
64
Describe where you can locate the Lopotrochozoa...
Within the Bilateria,
within the protostomia
within the spiralia
there you fine the Lopotrochozoa with contains 8 phylums. (majority of spirallian phylum)
65
Describe the charachteristics of the clade Lophotrochozoa...
-clade established on molecular evidance
-"lophophore"; crest carrying...crown of tenticles that surround the mouth
-"trochophore larvae"; wheel-carrying...bands of cillia that are used in locomotion and feeding.
66
Describe Deuterostomes...
-radial cleavage (embryo)
-blastopore becomes anus ("hence mouth seconds"
-enterocoelom
-gill slits in pharynx
67
what two groups can the deuterostomes be divided into?
-chordata
-ambulacraria
68
what 5 orders are found within the Ecdysozoa?
-priapulida
-kinorhyncha
-nematoda
-nematomorpha
-loricifera
69
Where can the order Priapulid be found?
Within the Ecdysozoa, within the Protostomes, within the Bilateria
70
Describe the order Priapulid...
- small number of species
-ancient species (can be used to date rocks)
-burrow in slime, with mouths open
-warty cuticle that seems segmented (organism isn't just looks it)
-body divided into presoma (barrel shape that can be retracted into trunk) and trunk (spiny)
71
Where can the order Kinorhyncha be found?
within the Ecdysozoa, within the protostomes within the Bilateria
72
Describe the characteristics of the Kinorhyncha....
-microscopic (less than mm)
-around 200 species
-live in mud or sand, feed on organic detritus or diatoms.
-body divided into 13 segments
-chitinous (chitin) cuticle
- head that is invertable (retract in), covered in circlets of spines.
73
Describe the phylum Nematoda..
-round worms/thread worms (not a true worm)
- 250,000 species at least..mainly parasitic.
-can be exceptionally abundant
-elongated, spindle shape. Tapered at both ends allows to get into small spaces.
-well developed sensory system
-oral stylet (needle like), 6 lips
74
Characteristics of free living Nematoda...
-saprophages ( feed on dead organic matter)
-model organisms (C.elegans)
-herbivores; use oral stylets (needles at mouth) to pierce plant cells and such contents
-predator; target soft bodied, slow moving prey. can be used for biological control.
75
What two types of nematoda are there?
parasitic and free living
76
describe parasitic nematoda...
-Intestinal Nermatodes; cause many high intensity infections
-Filarial Nermatodes; spread by blood feeding flies that inject the nermatodes into us
-can be used in pest control
e.g pinworms
77
Descrbe the phylum nematomorpha...
-"horse hair"/ "gordian worms"
-free living in fresh water as adults
-larvae are parasites of arthropods
-around 350 species
-very thin bodies with thick cutical
-no excreatory/digestive system, live off nutrients absorbed from hoast, adults survive on food stored.
-parasite-mediated behaviour modification, change behaviour of host (make host go to fresh water)
78
Describe the phylum Loricifera...
-sediment living
-protective outer lorica (shed to grow)
-invertible head
-oral stylets (needle like)
79
where do you find the superphylum Panarthropoda?
Found within the Ecdysozoa, within the Protostomia within the Bilateria
80
What phylums are found within the Panarthropoda?
-Onychophora
(next two classed as tactopoda)
-Tardigrada
-Arthropoda
81
Describe the characteristics of the Panarthropoda...
-Legs and claws
-ventral nervous system (runs along the bottom of the animal)
-segmented body
-contains Tactopoda (group that has a united nervous system and musculature)
82
Describe the Onychophora found within the Panarthropoda...
-"velvet worms"
-ancient group, marine origins
-around 200 species
-onychophoran body paln
83
Describe the Onychophora body plan...
thin, flexible cutical made of chitin. Worm-like, segmented body. Each segment has a pair of clawed, lobe-like legs. Head made of 3 segments (antennae, jaws and papillae)
84
How do Onychophorans reproduce?
-Indirect internal fertilisation; male packages sperm, and places on females. It dissolves through her body.
-Females larger than males (have more segments)
-can be viviparous (live bearing) or oviparous (egg laying)
-care for young
85
Describe Onychophora ecology...
Found in tropical/sub tropical and wet temperate areas. Specialised for life in leaf litter. Some species are social, aggressively defend territory from other groups
86
One of the 3 segments that make up a Onychophoras head is a papillae..what is this?
It can squirt glue like slime, forming strong nets that can help with defence or capture prey.
87
Within the Panarthropoda we find the Tardigrada, describe this phylum.
-"water bears"
-tiny, found in every biome in earth
88
Describe the body plan of the Tardigrada
4 body segments. Each segment has paired appendages, mostly head. Missing the genes that form the trunk in other segmented organisms. (probably due to becoming smaller than ancestors)
-exoskeleton with segmented plates on it
-no repiratory system (diffuse o2 in water)
-diffuses oxygen across body surface
-haemocoel (filled with blood with o2 dissolved in it), acts as a hydrostatic skeleton.
89
Describe Tardigrade ecology...
-Cryptobiosis (can go into a cryptic state that is basically impossible to kill with environmental conditions)
Most of Tardigrades life in normally spent in the state.
90
where do you find the Arthropoda?
within the ecdysozoa, within the bilateria
91
Describe the key charcteristics of Arthropoda..
-exoskeleton with jointed legs (arthropod means jointed leg)
-each segment has jointed appendages,usually specialised in function.
-Haemocoel (blood filled cavity)
-Dorsal heart (along upper body)
-ventral nerve trunks (bottom body)
92
what are the three main groups within the Arthropoda?
-Chelicerata (spiders/scorpians)
-Myriapoda (centipedes ect..)
-Pancrustacea (crabs, woodlice ect)
93
Sometimes the three main groups of Arthropoda can be grouped into 2 like...
combining pancrustacea and myriapods becuase of their mouth parts (mandibulata) and then the Chelicerata that have chelicerate mouth parts.
94
Describe the segmentation of Chelicerata...
Eye (with no appendage) and chelicera (mouth).
Next segment has pedipalps, then walking legs. e.g spiders
95
Describe the segmentation of Hexapoda...
Antenna (1 set) and eye, mandible, then maxillae and then walking legs e.g dragonflies
96
Describe the segmentation of Crustacea...
Antennae (2 sets) , mandible, maxillae, then walking legs(continue to the end of body) e.g woodlice
97
Describe the cross section of an Arthropod...
Heart at the top (dorsal) , Haemocoel (cavity with organs floating surrounded by blood, open circulatory system) in the middle with gut around it and nerve trunks at the bottom. Muscles attached on the inside to apodemes.
98
Describe the Arthropod exoskeleton...
Distinguishing feature of the Arthropod. It's rigid; provides protections and muscle attachment, waterproof barrier.
The skeleton has 3 layers;
1.epicuticle-wax/tanned proteins (tough)
2.exocuticle-chitin,pigments, thickend
3.endocuticle- chitin, flexible
99
What are some negatives of the Arthropod exoskeleton?
-limits growth (defines max size it can be)
-restrict diffusion/excretion
-reduces external stimuli
100
Describe the circulation of Haemocoel in Arthropods...
The heamoceol normally divided into sinuses by membranes. In upper sinus a contractile heart (dorsal), ostia to let haemolymph in.
The haemolymph bathes tissues, transports nutrients and somtimes cyanoglobin (respiration)
101
Describe the nervous system of Arthropods...
They have pair of ventral nerve trunks along bottom of insect. They have segmental ganglia at each segment, which act as the brain for each segment.
The "brain" is made of fused ganglia (cerebral ganglia) found at the top of the insect and has 3 parts.
1.protocerebrum-optic nervs
2.deuterocerebrum-antennal nervs
3.trticerebrum- seccond antennal nevers when present
102
Describe the last common ancestor of all Arthropoda...
The last common ancestor (500mya) has; modular body (segmented), chitin exoskeleton, branched appendages on each segment, ventral mouth, pre oral antennae, dorsal eyes (facing top of animal) , marine, sediment feeders.
103
What 3 groups do we find in the Chelicerata?
1. Pycnogonida
2. Xiphosura
3. Arachnida
104
Describe the key characteristics of the Chelicerata...
-translates to "claw" and "horn" describes there chelicerae mouth parts
-they can have chelae (pincers) which are modified pedipalps.
-body divided into 2 regions, the front= prosoma (2 pairs of appendages; chelicerae, pedipalps) then 3rd to 6th; walking legs. Back= Opisthosoma (up to 13 segments, tail spine and gonopore)
chelae=pincers
chelicerae= mouth parts
105
What are the 3 types of Chelae that a Chelicerate can have?
Chelae are pincers.
1.Jackknife; e.g spiders
2. scissors; e.g solifuges
3. sedimented chelate; e.g scorpions
106
What are 3 classes from the Chelicerats?
-Arachnida
-Merostomata
-Pycnogonida
107
Explain how the Chelicerate respire...
They have book gills/lungs (depending if they're aquatic), trachea (tubes through body that carry oxygen) and have Haemocyanin (copper based) respiratory pigment.
108
Explain how the Chelicerate digest food...
They have a pumping system for fluid food, use chelicerae to break up food (extra oral digestion). Arachnids have no jaws, so food needs to be liquid.
109
Explain how Chelicerates excrete waste products...
They have Coxal glands with pore at the base of leg, this waste is mostly guanine.
110
Explain how Chelicerates reproduce...
Male Arachnids- have pedipalps modified into copulatory organs (filled with sperms) To avoid becoming a snack the male will then do courtship dances, provide gifts and restrain the female.
111
Describe the Pycnogonida
A class of Chelicerata.
stilt like spiders. creepy looking.
Mouth is on a proboscis which extends down to floor, as they have stilt like legs.
Mostly carnivorous to sessile soft body invertebrates. Because body so small, use legs to pocket gut, this is called Caecae.
Narrow prosoma Sometimes males carry eggs in legs. Vestigial opisthosoma.
No organs for gas exchange as so thin.
112
Describe the Xiphosurea
order of Chelicerata. class merostomata. only 4 species. prosoma covered in large dorsal sheild, 5-6 pairs of respiratory appendages on opisthosoma. "book gills". Telson (spine). Their blood is an antibacterial agent. compound eyes and simple eyes.
113
Describe the Arachnida...
-Unsegmented prosoma (anterior region of the body) , typically with solid carapace (upper shell). -Chelicerae and pedipalps, 4 pairs of legs.
-No appendages on opisthosoma (heavily modified).
carnivorous. sensory hairs, eyes, slit sence organs (detect air pressure).
e.g scorpiones
114
what class does the Scorpione species fall into?
Arachnida.
115
Describe Scorpiones...
-many species/habbitats
-prosoma has chelate (claws) pedipalps.
-single sheild covers prosoma
-opisthosoma; mesosoma (broad segments), metasoma (narrow segments), telson (modified spine into venom gland and sting)
116
what class do the Araneae species fall into?
Arachnida
117
Describe the Araneae...
Spiders, prosomal segments fused. opisthosoma of 12 segments attached with narrow stalk. Joimted chelicerae with venom glands. leg like pedipalps for food handling and insemination (males), many eyes, silk glands
118
What class do the Mygalomorphae fall into?
Arachnida
119
Describe the Mygalomorphae...
-heavily built and hairy
-robust chelicerae that move up and down
-reduced spinnerets (don't really make silk)
120
what class does the Araneomorphae species fall into?
Arachnida
121
Describe the Araneomorphae...
90% of all spiders in this.
-Chelicerae move laterally
122
Describe the madibulata...
The pancrustacea and myriapods described as the mandibulata. Their mouth parts are described as mandibles
123
Describe the Entognatha...
Found within the Hexapoda, which is within the Pancrutacea of the Arthropoda. They are not Insecta, but do have 6 legs, normally wingless, mouthparts can retract into the head, all antennal segments have muscles.
124
What groups are found within the Entognatha?
Potura; no antennae, non contracile hearts
Diplura;long antennae, no eyes
Collembola; furcula (spring), collophore (water regulation)
125
Where can the group Insecta be found?
Within the Hexapoda group, which is within the Pancrustacea which is in the Arthropoda.
126
What does the word insecta translate to?
"notched"/ "divided"
127
Describe Insecta...
Hexapod arthropods have exsternal mouthparts and unbranched appendages. 3 body parts (head, thorax and abdomen), 5 sets of appendages, thorax has 3 pairs of walking legs.
128
Within the Insecta, what are the two wingless taxa called?
-Archaeognatha
-Zygentoma
129
Within the Insecta, what is the winged taxa called
-Pterygota
130
What is "darwinian" life?
a material system that undergoes reproduction,mutation and natural selection.
problem: one rabbit wouldn't be alive as it cannot reproduce
131
The 7 pillars of life definition?
-Koshland
Koshland
-program (plant of ingrediants)
-imporvisation (program can alter to environment)
-compartmentalised (separate from environment)
-energy (open metabolising system)
-regneration (compensation for loss)
-adaptability (overwrite program)
-seculuded (can chemically control internal)
132
What is a domain?
fundamental cellular differences e.g prokaryotic vs eukaryotic
133
What is a kingdom?
"kind" of life, e.g heterotrophic vs autotrophic
134
What is a phylum/divition?
groupings based on body plan
135
What is a clade?
distinct grade of organisation
136
What is a genus?
common origin, still distinct from one another
137
what is taxonomy?
the science of classification
138
What is cladistics?
approach to taxonomy where you organise organisms into a clade
139
What is a taxon?
a group of related organisms, at any degree
140
what is a clade?
group of taxa that all have a common ancestor
a grade would exclude some of the decendents
141
What is the morphospecies concept?
-by linnaeus (also did binomial naming system)
-if they look like each other, "conform to a fix type"
142
What is biological species concept?
group of actually or potentially interbreeding natural populations which are reproductively isolated from one another
-Mayr
143
What are some problems with the biological species concept?
Doesn't work for:
-asexual species
-extinct life forms (we don't know if they could breed)
-hybridisation
-ring species
144
What is the phylogenetic species concept?
a species is an irreducible group whose members are descended from a common ancestor and who all possess a combination of derived traits
145
What is a plesiomorphy?
ancestral trait, shared by two or more taxa
146
What is a apomorphy?
Derived trait unique to a taxon.
Can either be a synapomorphy or autoapomorphy
147
What is a synapomorphy?
derived trait shared by taxon and daughter taxa
148
What is an autoapomorphy?
derived trait that distinguishes it from its sister taxon
149
What is phylogeny?
evolutionary relationships between taxa.
can be based on morphology or genetics
150
Where can the paraphyletic crustacea group be found on the phylogenetic tree?
The arthropoda are split up into two groups the chelicerates and the mandibulata. Within the mandibulata in the pancrustacea which divided into the hexapods and also the crustacea
151
What are some broad characteristics of the "crustacea"?
-primarily marine
-dominant plankton (includes zooplankton to important for ecosystems)
-important component in benthos (sea floor), recycle nutrient (carbon)
-can be sessile/mobile
-6 parts for head, to pairs of antennae, branched appendages "fork".
152
What are the key characteristics of an archetypal crustacean?
1. Cephalon;
-5 segments, compound eyes, 2 sets of jointed branched antennae, may have a cephalothorax (sheild) or carapace (shell)
2.pereon (thorax);
-part of the thorax not incorporated into shell
3.pleon (abdomen);
-rear end, for swimming. (pleopods like paddles to swim)
153
Describe the gas exchange within crustaceans...
-most have gills requiring constant water flow.
Some decapods have branchial chambers;
-protect the gills
-provide ventilating current
-found between carapace and body wall
154
How may crustaceans feed?
-suspension feeders (feed on particles)
-filter feeders (feed on small animals)
-deposit feeders (organic detritus)
-predators
155
How do crustaceans reproduce?
-dioecious (2 separate sexes)
-copulation and internal fertilisation
-egg brooding (so look after eggs)
larvae have two phases then adult
156
What 4 classes comprise the majority of crustacea species?
-brachiopoda
-malacostraca (crabs, lobsters ect)
-thecostraca
-copepoda
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Which clade INCLUDES the modern amphibians, lizards, birds, and mammals but EXCLUDES the lungfish?
tetrapoda
158
Within the crustacea, there is a large class called malacrostraca, decribe them...
-3 body segments
1.head with 2 pairs of branched antennae
2.throacic
3.abdomen (we can use appendages on this to determine which version we have)
Straight digestive track (gastric mill, contain calcium carbonate to chew food inside stomach)
159
Within the crustacea, there is a large class called copeapoda, decribe them...
-dominant for marine plankton
-no carapace
They contain, groups that have split antennae, and some consume plankton
160
Within the crustacea, there is a large class called thecostraca, decribe them...
-barnicles
-sessile (therefore hermaphrodites) or parasitic
-throax and reduced abdomen (no carapace)
-they're filter feeders, and capture prey through cirri
-stick to surfaces by their antennules
161
Within the crustacea, there is a large class called branchiopoda, decribe them...
Includes clam shrimps, "sea monkeys" ect
-freshwater/brackishwater
-compound eyes
-carapace has valves that can open and close
-uses antennae to swim
162
What are insects?
hexapod arthropods, with external mouthparts and unbranched appenadages.
-3 body parts , head (6 segments antennae and eyes), throrax (3 segments each with a pair of appendages) and abdomen (11 segments, including copulatory)
-5 sets of appendages
-thorax contains 3 sets of walking legs
-basically all have wings
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what does pteron mean?
winged
164
What does pterugotos mean?
not winged
165
How do insects respire?
Tracheal system.
spiricles is a tube going into tracheal trunk to all cells (highly branched). With a rhythmic pumping. Some aquatic larvae may also have gills.
166
Insects use mating signals such as...
oudour, sound, colour or mating behaviour
Internal fertilisation, females genrally mate once and then just store sperm for next time she wants to lay eggs
167
What 2 major patterns of development are there in insects?
-incomplete metamorphosis, egg hatches into an insect that looks similar to the adult and just grows larger and the go through some malts to become a complete adult
-complete metamorphosis, egg hatches into a form that looks very different from adult. Then eventually form a sessile malt which is a complete reorganisation of body plan
168
what group do the winged insects belong into?
neoptera
169
What 3 groups are in the the neoptera (winged insects)?
-polyneoptera (incomplete metamorphosis, unspecialised mouthparts)
-paraneoptera (incomplete metamorphosis, specialist mouthparts)
-holometabola (complete metamorphosis, range of mouthparts)
170
Where does the name spiralia come from?
Spiral cleavage of their embryo
(all protostomes have this though)
171
What are the characteristics of the spiralia?
-spiral cleavage of their embryo
-otherwise defined as lacking attributes from the ecdysozoa
-validity of this group through genetics
-bilatrally symmetrical
-legless
-soft bodied
172
What are the two major divisions of the spiralia?
lopotrochoz
oa and gnathifera
173
Describe the gnathifera...
Within the spiralians.
-jaw bearing (made of chitin)
-anus on dorsal side
-direct development (no larval stage)
174
What phylum are there in the gnathifera?
-chaetognatha (arrow worms, predatory, neurotoxin to kill prey)
-rotifera (wheel animals, this wheel of cillia for locomotion and filter feeding ,sessile,free living, mastax to grind food)
-acanthocephala (thorny headed worms,paracitic,and paracitic induced behaviour 2 hosts in life cycle)
-gnathostomulida (jaw worms, slender, found at bottom of sea, no circulatory or respiratory systems)
don't worry too much about all this
175
what phylums are found in the flat worms and hairybacks?
platyhelminthes, gastrotricha
176
What are the characteristics of platyhelminthes?
-flatworms
-no body cavity (lost celome)
-no transport/repiratory/or waste systems are so flat
-blind ended digestive track (only take in what they need)
-can be free living (turbellaria) or parasitic (trematoda-flukes) and (cercomeromorpha-cestoda, tapeworms vertebrate parasites contain scolex, proglottids
177
Where does the word lophotrochozoa come from?
They have
-"lophophore", crest of cillia for feeding
-"trochophore",wheel bearing shape for larvae
178
What phylums are found in the lophophorata?
-brachiopoda (lamp shaped, secrete a shell around them, dorsal and ventral valve)
-phoronida (horseshoe worms, chitin tube to live in)
-entoprocta (goblet shaped body,clonial and shared body parts)
-ectoprota (moss animals, live in secreted houses
179
What traits do the lophophorata share?
-circular or "u" shaped mouth with 1-2 rows of tentacles for food collection (plankton feeders) and gas exchange
-sessile as adults
-u shaped gut (so mouth and anus close to each other), entoprocta is an exception
-brachiopoda
-phoronida
-entoprocta
-ectoprota
180
What are the lophotrochozoa that don't fall into the lophophoratans?
-cycliophora
-nermatea
-annelida
-mollusca
181
What are the characteristics of the cycliophora?
part of the lophotrochozoa
-single genus contained
-symbiotic on the mouthpartsof coldwater lobsters
-ring of cillia take up food into u shaped digestive track
-asexual adult
-pandora larvae (reporduces adult self by budding) or female produced inside itself for reproduction
182
What are the characteristics of the nemertea?
part of the lophotrochozoa
-ribbon worms
-free living and carnivorous
-locomotion by cillia
-dioecious, with internal/external fertilisation
-have eversible probosis used to capture prey
183
Where can you find the mollusca group?
the protostomia separate into the spiralia which separate into the lophotrochozoa where then you can find the mollusca
184
What 3 major characteristics must we consider when thinking about molluscs?
-the foot
-the visceral mass
-the mantle
185
is the shell of a mollusc part of the species or secreted?
it is secreted
186
Describe the molluscan foot?
-large muscular structure that is both locomotive and supports internal organs
-in squids and octopus it has been modified to form the arms and tenticles
-contains a pair of statocysts (balance sensors, for which way gravity hits)
-can also secrete mucas, to reduce friction to move
187
Describe the molluscan visceral mass?
-dorsal concentration of internal organs (stomach, heart, nephrida-kidnys, gonads-reproductive organs)
-defined head with eyes and cephalic tenticles
-open circulatory system, using hemocyanin
-two pairs of main never chords (brain surrounds oesophagus)
188
Describe the mollucan mantle?
-a fold of tissue covering the visceral mass
-often extends beyond to form a mantle cavity (contains anus, gills, nephrida,gonads and chemical sensory sensors)
-secretes hard calcareous skeleton
189
How do molluscs feed?
-most are herbivorous, or filter feeders
-cephlapods (squid/octopus) primarly predatory
-some also use venomous darts
-radula (made of chitin, scrape at food matter)
190
describe the reproduction of molluscs?
-sexual reproduction
-dioesous or hermaphroditic
-aquatic species have extrenal fertilisation
-terrtrial have internal
have tropaphore larva
191
What are the classes within the mollusca?
-aplacophora (deep water worm like0
-monoplacophora (deep ocean, week muscular foot)
-polyplacophora (the chitons, large foot, no eyes, aesthetes-work like eyes, 8 plates in shell)
-bivalvia (encased in valve, suspention feeders,gills)
-gastopoda (torsion, developed food and head,spiral coil head)
192
What is torsion in gastropods?
occurs during development of all gastopods, gut becomes twisted over each other. Happens in two stages.
