Midterm 1 Flashcards
(166 cards)
1
Q
what are the 5 defining traits of chordates
A
-notochord
-dorsal neural tube (nerve cord)
-pharyngeal slits (some only when embryos)
- endostyle
- post anal tail
2
Q
what are myomeres
A
blocks of muscle separated bt connective tissue
3
Q
What is the basic anatomy of cephalochordates
A
myomeres and notochord run the length of the organism
leaky pharyngeal slits
no fins
4
Q
in cephalochordates, where do pharyngeal slits leak into
A
atrium - space around guts
5
Q
what way can a notochord move
A
can bend laterally, but cannot be compressed (axially)
6
Q
what is the structure of a notochord
A
consists of cells and fluid in a tough sheath
7
Q
are all chordates vertebrates
A
no
8
Q
why are cephalochordates call that
A
notochord extends into head
= cephalo (=head) = chordate (=notochord)
9
Q
what shape are myomeres in chephalochordates
A
V shaped
10
Q
what work together to allow cephalochordates to move
A
notochord + muscles
11
Q
what does coordinated contraction of muscles in cephalochordates allow for
A
side bending and swimming
12
Q
when is dorsal neural tube developed
A
in embryo from infolding of ectoderm
13
Q
how complex is nervous system in cephalochordates
A
simple, no brain or well developed sensory organs
no eyes but controls movement
14
Q
how does cephalochordates eat
A
suspension feeders
cilia create a water current to draw food in
food gets trapped by mucus
15
Q
what are pharyngeal slits
A
openings in the wall of the pharynx that allow for one way water flow
16
Q
what is different between the function of pharyngeal slits in cephalochordates and later species
A
in cephalochordates, play role in feeding
in later groups developed a role in respiration
17
Q
what are pharyngeal slits supported by
A
pharyngeal arches
18
Q
what are endostyles
A
ciliated glandular groove on the floor of the pharynx
19
Q
what is the endostyle homologous to
A
thyroid gland,
20
Q
what does homologous mean
A
similar in position, structure, and evolutionary origin but not necessarily in function
21
Q
what do both the endotyle and the thyroid have functions relating to
A
both involves in iodine metabolism
22
Q
what is the circulatory system like in cephalochordates
A
closed system and with blood vessels
blood is plasma like, no blood cells or pigments
23
Q
do cephalochordates have a post anal tail
A
yes
24
Q
what is a monophyletic group
A
=clade
an ancestor and all of its descendants
25
what is a paraphyletic group
an ancestor and some but not all of its descendants
26
what is a polyphyletic group
2 or more groups but not their common ancestor
27
what is an outgroup used to distinguish
distinguish ancestral from derived characters
28
what is homology
a trait found in more than 1 taxon that arose from a common ancestor
29
what is synapomorphy
a trait that is shared and derived due to common ancestry and that is usique to a group
30
what define monophyletic groups
synapomorphy
31
what is convergent evolution
when 2 or more taxa evolve the same trait independently
32
what is homoplasy
a shared derived trait that is not due to common ancestry
33
what evidence is used to build phylogenetic trees
- Fossil record
- comparative anatomy
- embryology
-molecular data
34
what are the biases in the fossil record
- anatomy : hard body parts last
- environment: aquatic preserves better
- temp+chemistry: cooler and low oxygen favours preservation (slower decomposition)
- quantitative factors: easier to find larger things, easier to find abundant things, easier to find species that existed longer, easier to find individuals with a wider range
35
what are the shared arm/hand traits in many vertebrates
1 bone (humorous) ---> 2 bones (ulna and radius) ---> many (carpels) ---> 5 (fingers)
36
apart from the 5 chordate features, what other traits to vertebrates share
- vertebrate
- cranium
- brain
- pituitary (endocrine system)
- multichambered heart
- mineralized tissues
- hox genes
37
what do vertebrae do
protect the neural tube and notochord, and may anchor other structures
38
what are arcualia
precursor to vertebrae
39
all vertebrates have a head with what characteristics
-cranium
- brain
- pituitary gland
40
what is the cranium and what is it made of
skull
formed of cartilage and or bone
41
what does the anterior part of the neural tube swell to form
brain
42
what does the pituitary gland do
produces and regulates hormones
43
what do hox genes regulate
development
44
how did hox genes contribute to the origin of vertebrates
non- vertebrates have a single cluster of hox genes , vertebrates have 2 or more
- the duplication of hox genes allowed for more complex development and phenotype
45
what are gill slits
modified pharyngeal slits with filaments for respiration
46
how does water move through pharynx in early vertebrates
by muscular pumping
47
what is the circulatory system like in early vertebrates
closed circulatory system with blood vessels
3 chambered
blood has red blood cells with hemoglobin and transports o2 and co2
48
what are agnathans
jawless, early vertebrates
49
agnathans are a _______ group that comprise vertebrates without jaws
paraphyletic
50
what was life like in the Cambrian
no life on land
animals are diverse and are most abundant on continental shelves
51
when did metaspringgina live
Cambrian
52
what are the physical characteristics of metaspriggina
gills
dorsal neural tube and brain (evidence of eyes)
notochord
w shaped myomeres
no mineralized tissue or fins
53
what did metaspriggna support
is very similar to the proposed hypothetical vertebrate ancestor
54
what do cyclotomies include
2 extant groups: hagfishes and lampreys
55
what traits do cyclosomes have that the hypothetical vertebrate ancestor
gills, gill chambers, gill arches
notochord
nerve cord and brain
heart with 3 chambers, has RBC with hemoglobin
56
what do hagfish have that the hypothetical vertebrate ancestor didn't have
poorly developed eyes (ancestors probably had fully developed eyes)
lack a lateral line system (lost it, ancestral to vertebrates)
highly specialized feeding structures
57
what did finding condonts show
shift from suspension feeding to predatory feeding
58
what is some of the oldest mineralized vertebrate tissue
conodonts
59
what was it like in the ordovician and silurian
first land plants, vascular plants, and fungi
arthropods colonize land
diversification of jawless fishes with mineralized tissues
60
what are ostracoderms
armoured jawless fishes
61
what are the potential advantages of mineralized tissues
protection
mechanical abrasion
structure
mineral storage
buffer blood
62
what is hydroxyapatite
mineralized tissue exclusive to vertebrates
includes calcium and phosphate (inverts use mostly calcium)
63
why do vertebrates use hydroxyapatite
more stable in acidic environment which is caused by higher metabolic activities
64
what are odontodes
first mineralized vertebrate structures
little tooth like elements
65
where were teeth first observed
conodonts
66
what does oxygen content in water vary with
temperature: as temperature increases, oxygen decreases
salinity: as salinity increases, oxygen decreases
67
what does breathing water efficiently require
- gills
- flowing water
- flowing blood
68
what is ram ventilation
the fish swims with its mouth open, forcing water over gills
- used by many sharks and some large and fast fish
69
what is buccal pump ventilation
- suction phase: the buccal chamber expands, creating negative pressure that draws water through mouth
- force phase: the mouth closes, creating positive pressure that forces water out through gills
- used by some sharks and most fish
70
what kind of circulatory system do sharks have, and what is the pathway
single circuit system
blood flows from the heart through the gills where it is oxygenated, to the body. Veins bring deoxygenated blood back to heart
71
why do gills have so many lamella (filaments)
lost of SA for gas exchange
72
why are gills efficient
they have a large surface area for gas exchange
short diffusion distance - gas exchange takes place in capillary beds, which are 1 cell layer thick, minimize diffusion distance
73
what do interbranchial septa do
provide support to keep the gill filaments separated and exposed to flowing water
74
gnathostomes are a _____ group
monophyletic
75
what are gnathostomes
jawed fishes
76
Apart from cordate features what are other shared derived traits that gnathostomes have
second his gene duplication
jointed gill arches
jaws with teeth
paired fins
more developed vertebrae
77
what are true teeth
teeth embedded in jaw
78
how did jaws evolve
ancestral condition - visceral arches unjointed
evolutionary changes - visceral arches become jointed, 1st gill slit becomes a spirale, 1st visceral arch becomes jaws, 2nd visceral arch becomes hyoid arch
79
is evidence of the origin of jaws seen more in development or fossils
development
80
what is the evidence that jaws evolved form gill arches
- jaws, hyoid, and gill arches share similar developmental origin
- nerves and blood vessels that support gill arches and jaws are similar
- nerves and blood vessels that support spiracle and gill slits are similar
- muscles that support jaws are related to muscles that support gill arches
81
what is the ventilation hypothesis
development of jaws involve changes in reorganization of mandibular arch and hypobranchial muscular which increased gill ventilation
further development allowed for prey capture through suction feeding
Jaws allowed for more forceful opening and closing of mouth
82
why were paired fins developed
as fish move faster there is a greater chance of instability
fins increase stability
83
what fins are relayed you what axis of movement
vertical: tilt - pectoral find
left and right: - tail fin
rotational: roll - dorsal fin
pectoral helps all
84
what are the 2 theories of how paired fins developed
fin fold theory: resulted from genetic program, genes are turned off/on in specific regions giving rise to pectoral and pelvic fins
gill arch theory: fins are homologous with gill rays, and girdles are homologous with gill arches
85
gnathostomes are a ________ group
monophyletic
86
what is a placoderm
armoured jawed fishes
87
what jaw moves when placoderm opens it
upper jaw
88
Chondrichthyes are a ________ group
monophyletic group
89
what was life in the Devonian like
on land seedless vascular plants have diversified and are as big as trees
In ocean: the age of fishes, all 4 lineages present
90
what are defining characteristics of Chondrichthyes
cartilaginous skeleton
claspers
91
what kind of bones did the ancestors of Chondrichthyes have
bony
92
what are placoid scales (denticles) similar to (in terms of development and structure)
teeth
93
how do sharks replacement teeth work
teeth are part of a developing whorl
94
what does jaw suspension describe
how the mandibular arch articulates with the chondochranium
and the role of the hyoid arch
95
what is an autodiastylic jaw suspension
when upper jaw is firmly attached to the cranium at 2 points
hyoid arch isn't involved in jaw suspension
96
what are ampullae of lorenzini
on sharks rostrum
detect electrical fields
97
what is the lateral line system
clusters of specialized cells allow sharks (and other fish) to detect vibrations and pressure gradients in the water
can detect movement of prey
98
what is holostylic jaw suspension mean
and what is its benefit
upper jaw is fused with the chondrocranium
gives strength and low flexibility
99
what is a helicoprion
spiral tooth whorls
100
what were early sharks like
mouth: terminal-- front instead of tucked back below
fins: caudel fin has upper/lower lobe that are similar in size and shape (triangle shape), rigid traingle shape
amphistylic jaw suspension
101
what is amphistylic jaw suspension
and what is this jaw like
upper jaw is attached to chondrocranium anteriorly by ligaments and the posterior is supported by the hyoid arch
looser connection than autodistylic jaw suspension
102
what is oviparous
laying eggs outside of body
103
what is ovoviviparous
eggs develop inside female (pregnancy)
104
what are adaptations sharks have to reduce overall density
- larger liver - lipid oil rich, oil less dense than water
- cartilaginous skeleton - less dense than bones
105
how do fins help keep shark buoyant
uneven tail lobes create lift, which would tip noise down, so pectoral fins counter this
106
what is hyostylic jaw suspension
upper jaw is attached anteriorly by ligaments to the chondrocranium
also hinged posteriorly by the hyomandibula
works like a swing
107
what does modified hyostylic jaw suspension allow for
greater suction feeding
108
what is dermal bone
formed in the skin and not dependent on cartilage
109
what is endochondral bone
bone that replaces cartilage and forms from specialized cells deep within the body
110
what are the 3 parts that comprise a fish skull
chondrocranium - brain case
splanchnocranium - part of jaw
dermatocranium - part of jaw
111
what bones are on upper/lower jaw
upper: premaxilla and maxilla
lower: dentary
112
when development of gill arches what did the fish not need anymore
loss interbranchial septum because gill arches support gills
113
what were the early vertebrae
cartilage that wrapped around neural tube and blood vessels
114
what are AOs (air filled organs) and what is their function
either lungs or gas bladder (swim bladder)
Contribute to respiration and buoyancy
115
what is the difference between a swim bladder with/without a pneumatic duct
with: gas bladder connected to gut, fish burps/gulps to control its volume, contributes to buoyancy and if with veins also gas exchange
without: no connection between gas bladder and gut. fish controls volume by releasing gas from blood, contributes only to buoyancy
116
what is the evidence that lungs (fish and tetrapod) and gas bladders are homologous
arise from pharynx
developmental similarities in supply of arterial blood
similar chemicals that help with gas exchange
similar histology
117
what are the hypotheses for the development of lungs
- evolved in shallow water (more oxygenated water) and gulped water and eventually accidentally air, would store air in primitive lungs
- main advantages of lungs was that they provide oxygen to heart. proposes that coronary arteries are not ancestral
118
what are actinopterygii
ray finned fishes
119
actinopterygii is a _______ group
monophyletic
120
what are sracopterygii
lobe finned fishes
121
what was the trend in actinopterygii fins
reduction of skeletal elements, made fin more maneuverable or collapsible
shift from heterocercal to homocercal caudal fin (2 parts --> 1)
pectoral fins shift from ventral to lateral position, and continue to articulate to skull
pelvic fins remain unattached to axial skeleton and shift towards anterior
122
what does the gas bladder do
provides neural buoyancy and frees fins for additional functions
123
what are the advantages of actinopterygii fins
greater maneuverability
including rapid turning and stopping
124
what changed for teleosts in regards to jaw protrusion
mandible hinges open and the pre maxilla slides forward
allows for strong sucking
125
what are pharyngeal jaws
teeth in parynx
assists in prey capture and used for mechanical digestion
126
what is the trend in sacropterygii fins
increase im skeletal elements that support the fins
127
what would a single fat filled lung be useful for
if you live deep down where there is little oxygen
also helps with buoyancy
128
what was Devonian like
greening of land, emergence of forests
lots of shallow coastal inland seas, deltas, estuaries
129
what era did tetrapods begin
Devonian
130
what was a trend with skulls in the Devonian
become flatter and wider
loss of bones that connect pelvic girdle to head (evolution of neck)
131
what are the different angles of pectoral fins good for (angled outwards/backwards)
Backwards: good for a fin
outwards: more robust
132
what is a trend in the pectoral girdle in Devonian
shift in support from external dermal bones to internal endochondral bones
133
what is a trend in pelvic girdles in Devonian
increases in size and dominance
becomes weight bearing
134
are big eyes more advantageous in water or land
land
135
could Devonian tetrapodish organisms breath water or air
retained ability to breath water with gills and air with spiracles
136
what happened at the end of the Devonian
mass extinction
137
what was the carboniferous era like
extensive seedless vascular plants and forests
increased o2 levels
tetrapods adapt to land
diversification of insects
138
why move to land
push factors:
competition of resources, predator avoidance, to deal with droughts or large tides
pull factors: feeding - new prey, sun basking (they were cold blooded)
139
do organisms feel more resistance moving though water or air
water
140
does gravity have a greater effect on organisms on land or water
land
141
what are aquatic vertebrates shaped by
resistance and compression
142
what are terrestrial vertebrates shaped by
gravity
143
what was unique about Pederpes
weight bearing legs
terrestrial locomotion
144
what was the steps of walking (transition to land)
limbs/fins used for propulsion, body supported by water
belly dragging
walking, limbs bear weight
145
what provides a larger amount of oxygen in same volume, air or water
air
146
what was unidirectional water flow replaced with when started breathing air
tidal air flow (in/out through same hole
147
what changed in how air got into lungs with more developed breathing
air is now pulled into lungs instead of being pushed
148
does suction feeding work in air
no
149
what did the spiracle evolve into
middle ear
150
what does the stapes do
amplifies the waves and transmits them to the inner ear
151
what are the two stresses that terrestrial vertebral column have to deal with
buckling - stress of gravity pulling down on vertebral column
torsion - stress from twisting on the spine when walking (when not all limbs on ground)
152
what are zygapophyses
projections on front and back of neural arches that articulate with each other
prevent buckling
153
what characteristics do lissamphibians have
tetrapod skeleton and walking
senses - including hearing and stapes
eggs laid in water
unspecified carnivores
154
what is cutaneous respiration
breathing through skin
155
what helps reduce mixing of oxygenated and deoxygenated blood in the ventricle
currents
and a spiral valve
156
what are anorans
without tail (frogs and toads)
157
what do amniotes mark
the transition to a fully terrestrial life
158
what is an amniotic egg
air breathing air
ancestrally develop within a shell, though was lost in many mammals and marsupials
159
what make up amniotic eggs
amnion - fluid that surrounds the developing embryo (amniotic fluid)
yolk sac - contains nutrients which supports the embryo
allantois - stores nitrogenous wastes produced by developing embryos. also contains surface blood vessels that function in gas exchange though the cell
chorion - outer membrane that encloses 3 lower membranes
albumen - protein rich solution that provides water and nutrients
160
what do pores in egg shells allow
gas exchange
161
what problem did amniotic eggs solve
since embryo is suspended in fluid, can develop on land with desiccation and by minimizing the effects of gravity on embryo
162
what is an anapsid
has no temporal holes
163
what is a synapsid
1 pair of temporal holes
164
what are diapsids
2 pairs of temporal holes
165
where do temporal holes form
at joints where bones fail to meet during development
166
what did temporal holes allow for
muscles to attach and expand outside of skull
allows muscles to get bigger snd longer without needing a bigger skull
