Final Exam Review Flashcards
(224 cards)
1
Q
“Whole-Organism” Biology
A
Form -> performance -> ecology
Ex. Form: animals with wings tend to fly
Unique aspect to ecology based on form and performance
2
Q
Organismal Biology
A
Research at the level of the whole organism, integrated over structure (anatomy, morphology), function (physiology, behaviour), ecology, and evolution (phylogeny)
3
Q
Functional Morphology
A
focuses on the link between form (morphology) and performance
*within a species or population, morphological variation
4
Q
Ecological Morphology
A
focuses on the link between performance and ecology (ecomorphs and ecomorphotypes)
*typically not distinguished from functional morphology
5
Q
Integrative biology
A
- near synonym for organismal biology
- brings different aspects of organisms and their environment together
6
Q
Comparative biology
A
an area of research that attempts to explain biodiversity and its adaptive radiation in a phylogenetic (historical) framework (comparative method)
7
Q
Natural history
A
the scientific study of the organism in its natural surroundings
8
Q
Kinds of Chordates
A
Tunicata (formerly Urochordata) - tunicates & sea squirts (~2150-3000 species) Cephalochordata - lancelets Vertebrata (~6400 species)
9
Q
Characteristics of Chordates
A
Notochochord
- incorporated in vert. column in vertebrates.
- role in sinusoidal lateral undulation (fish)
Dorsal Hollow Nerve Chord
- brain at anterior end in vertebrates
Pharyngeal gill slits
- involved in filter-feeding & gas exchange; gill arches become jaws & other structures in vertebrates
- humans have gill slits in early embryonic development
Endostyle
- homologous with thyroid gland in vertebrates
- mucus which serves to capture food in filter feeding (lancelet)
Muscular Postanal Tail
10
Q
Pattern vs. Process
A
Phylogeny vs scenario
Pattern = what we see, diversity, phylogeny
Process = what we’re trying to get at
Phylogeny uses pattern to try and determine the process -> scenario is a hypothesis
11
Q
Aspects of morphology (anatomy)
A
Comparative
- differences and similarities between groups
Functional
- structural, how groups work, adaptation
Transitional
- macroevolutionary change
- pattern vs process
12
Q
Morphology
A
form of living organisms and relationships between their structures
13
Q
Phylogenesis
A
evolutionary development and diversification of a species or group of organisms, or of a particular feature of an organism
14
Q
Ontogenesis
A
development of an individual organism or anatomical or behavioural feature from the earlier stage to maturity
15
Q
Characteristics of vertebrates
A
Internal skeleton
- bone &/or cartilage
Vertebral column with cranium at anterior end
- vertebrae are rudimentary in lampreys and lacking in hagfish but fully formed in gnathostomes
Spinal nerve cord with brain at anterior end
Neural crest & ectodermal placodes
- NC = PNS
- EP = CNS
Hox Genes
- seen in inverts but more prominent and ##s in vests
16
Q
Neural crest
A
temporary group of cells unique to chordates Gives to: - PNS - melanocytes - craniofacial bones - cartilage - connective tissue
17
Q
Ectodermal placodes
A
area of thickening on the embryonic head ectoderm layer Gives rise to: - CNS - hair follicles - feathers - teeth
18
Q
Monophyletic
A
A taxonomic group that holds characters descended from a single common ancestor
- all organisms related and embraced through most recent ancestor
19
Q
Synapomorphy
A
An advance character state shared among two or more taxa inherited from the most recent common ancestor whose own ancestor in turn is inferred not to have such traits and is derived through EVOLUTION
** can be seen through modified version of traits
syn = with/together with
app = away from
morph = shape
20
Q
Homoplasy
A
Similar biological trait acquired by species from different (unrelated) lineages
- convergence
ex: bat and bird wings
21
Q
Polyphyletic
A
Taxonomic groups that have similar character states that descends from one or more ancestral lineage
ex: flying vertebrates are polyphyletic because bats and birds separated developed flight but don’t share a common ancestor
22
Q
Paraphyletic
A
A biological taxonomy that pertains to a certain group of organisms does include some but not all of the descendants from the common ancestors
- all descendants of last common ancestor separate to form another group
23
Q
Heterochrony
A
rate of morphological transformations accomplish by the developmental timing of events over evolutionary time leading to changes in size and shape
- changes in timing of expression of genes
24
Q
Heterotopy
A
change in position of the expression of a gene (new location)
25
Heterometry
changes in the amount of a gene product
26
Heterotypy
change in the type of gene product
27
Gnasthostomata
defined by presence of jaws with teeth and limbs (including fins)
28
Chondrichthyes
Sharks, skates, rays
cartilaginous
has live and egg bearing species
29
Osteichthyes - euteleosts
Osteichthyes = bony
~95% of living fish
includes live and egg bearing
marine and land feeders
30
Tetrapoda
Defined by presence of limbs w/ digits (not always), for terrestrial support and locomotion
Also has:
- internal nostrils (passageway from nose to mouth cavity + nose breathing)
- tympanic membrane and stapes (to detect airborne sounds)
- strong skeleton for support against gravity
31
Lissamphibia
- think skin for respiratory gas exchange, water exchange
*environmentally influenced due to change from environment
- complex life cycle with metamorphosis
(aquatic egg -> aquatic larva -> aquatic/terrestrial juvenile -> adult)
**not set in stone, lots of variation
- tend to be found in moist places due to water loss and more active at night
32
Amniota
Defined by amniotic off and exclusively internal fertilization
*less susceptible to desiccation because bigger but size is limited from egg
33
Allantois & yolk sac
- Allantois and yolk sac = gut, provide nutrition for embryo
- yolk shrinks because it gets used up
- allantois grows because it has excretions and lines amniotic egg
- all blood vessels in allantois
34
Reptilia
- thicker skin
| - covered in epidermal scutes (keratin)
35
Aves
- highly modified reptiles (archosaurs)
- endothermic
- body covered with feathers but retain epidermal scutes on legs
- feathers and scutes made of keratin, feathers for insulation
- wings and numerous other modifications for flight
- highlights modified haw with beak and no teeth
36
Mammalia
- endothermic
- body covered with hair/fur (keratin)
- highlights differentiated dentition
- numerous derived traits in skeleton (squamosal-dentary jaw joint, 7 cervical vertebrae)
- pinna (external ear)`
37
Polymorphism
The occurrence together in the same habitat of two or more discontinuous forms, or "phases", of a species in such proportions that the rarest of them cannot be maintained merely by recurrent mutation
**genetically determined variants
38
A few mechanisms for maintaining polymorphisms
- temporal variation of environment
- spatial variation of environment
- migration balancing selection
- heterozygote advantage
39
Polyphenism
phenotypic plasticity
- multiple phenotypes in population (polymorphic), but not based on genotype
- phenotypic change w/in an individual that is induced by an environmental cue
- often reversible
- behavioural shifts common, but morphological shifts also occur
- good example in amphibian larvae - shifts in morphological phenotype due to predators, competitors and prey
40
Type of selection
- natural selection (variation in a trait, heritability, differential survival/reproduction -> leaves a diff. # of descendants)
- artificial selection
- adaptation
- directional selection
- balancing selection
- disruptive selection
41
Sexual selection
- differences in mating success
2 mechanisms:
- competition for mates (usually male-male or sperm)
- mate choice (usually by females)
- responsible in part for sexual dimorphism (size, ornamentation, dichromatism)
42
"Species" is used to
- Describe groups we recognize
| - describe what the animals themselves recognize
43
Hybridization
- shapes evolution
when 2 species mate and produce fertile offspring, evolution can take new turns: backcrossing introduces new genes into the parent species' genomes (introgression) or hybrids start to breed only with other hybrids forming new species
44
Speciation
Hybrids mating among themselves can lead to a new species
45
Introgression
New DNA joins the parent's genome if a hybrid mates back with a parent-species
46
Parthenogenesis
Clonal
- species are all female
- reproduce strictly clonal-y
- egg is unchanged
- offspring identical to parent typically
47
Gynogenesis
Clonal
- effectively all female species
- mate with males of related species
- egg is unreduced by meiosis
- sperm only STIMULATES the process
48
Hybridogenesis
Hemiclonal
- half the genome is passed intact to the next generation while the other half is discarded but restored by mating
- hybrid of two parental species
- undergoes meiosis
49
elements of speciation
- reproductive isolation (isolation from related forms)
- genetice divergence (isolated reproduction)
- phenotypic divergence (look different because changing in different environments)
50
Post-mating but pre-zygotic isolation
Interspecific pairs form but fertilization does not occur
- Gamete variability: sperm do not survive in the female reproductive tract
- Gamete recognition: sperm do not recognize the eggs or are incompatible with them
51
Post-zygotic isolation
Interspecific hybrid zygotes are formed but have reduced fitness
- Hybrid inviability: interspecific zygotes have a reduced probability of survival to maturity
- Hybrid sterility: interspecific zygotes have reduced fertility
- Hybrid breakdown: hybrids produce sterile or inviable offspring
52
Allopatric
physical separation of diverging species
(geographical separation)
- go on own evolutionary pathway
53
Parapatric
Geographically adjacent
| - two diverging forms are geographically but only just, areas touching so exchange could happen
54
Sympatric
common space/range
| geographically coincident
55
Ecological speciation
evolution of reproductive isolation between populations by divergent natural selection arising from differences between ecological environments
**spatial scale can be small
56
possible outcomes of secondary contact after long period of separation
- partial or complete reproductive isolation
- hybrid zones
- complete introgression (might not have differentiated)
- selection for reproductive isolation (species a could identify and prefer species A)
57
Numerical taxonomy
Unweighted characters, quantitative (supposedly objective)
58
Molecular taxonomy
proteins, RNA, DNA
| comparing apples and oranges
59
Cladistic (Phylogenetic) taxonomy
shared evolutionary novelties
| uses morphological traits
60
Classification
ordering of organisms into sets based on relationships (criteria)
relationships are defined in various ways (e.g. phylogeny, resemblance)
61
Identification
allocation of previously unidentified specimens to the correct sets (keying)
62
Taxonomy
the theoretical study of classification, including principles and procedures (rules); a related word is taxon, which is a general term for any taxonomic group of any rank
63
Systematics
the study of diversity and interrelationships of organisms, and causes and origins of relationships, including zoogeography; broader than taxonomy
**most developed form, broadest, cause of origins and relationship
64
Linnean classification system
```
Kingdom
Phylym
Subphylum
Class
Subclass
Order
Sborder
Family
Genus
Species (Binomen)
Subspecies (Trinomen)
```
65
Denfensive noise-making in snakes
Crotalus: rattling (loosely interlocking modified scales & segments)
Pituophis: tail-vibrating; hissing (morphologically specialized for hissing), could be a form of mimicry
Echis: scale-rubbing ("stridulation")
Micruroides and gyalopion: cloacal popping
66
Homoplasy
- "false" evolutionary resemblance (similarity to species can lead to classification to not related descent)
- parallelism, convergence, reversal, loss, mimicry
- can confound construction of phylogenies
- but can be used to make inferences about adaptation
67
Convergent evolution
convergence
evolution of similar phenotypic features independently in different lineages, usually from different antecedent features, and assumed to involve different developmental pathways **can be concurrent or millions of years apart
68
Parallel evolution
Parallelism
evolution of similar or identical features independently in related lineages, usually considered to be passed o similar modifications of the same developmental pathways
69
Homology
- "true" evolutionary resemblance
- difficult to define precisely - relative term
Determined from:
- comparative anatomy
- fossil record
- developmental biology
- distribution of character states among taxa *using parsimony)
70
2 kinds of homology
Taxic = trait that helps define the group
Transformational = link groups
-> polar = direction of change
71
Tetrapod wings
homologous as tetrapod limbs but homoplasious as wings
bat, bird and pterosaur
these groups are tetrapods based on these limbs, same bone pattern.
wings are not homologs because they derived separately into different groups
72
Monophyletic group
ancestor plus all descendants
73
Paraphyletic group
“monophyletic” group with some descendants missing (e.g. “reptiles” lack birds)
74
Polyphyletic group
a group composed of members separated by two or more ancestors
composed of different species from distantly related groups
(ex: grouping pterosaurs, bats and birds)
75
Synapomorphy
shared derived trait
different construction of structures allows to separate groups
ex. all haves have a heart but birds have different hearts than reptiles
76
Symplesiomorphy
shared ancestral trait
77
Anagenesis
change within
| species formation without branching
78
Clades and grades
```
clades = monophyly
grades = paraphyly
```
79
Grades attributable to
synapomorphy -> monophyletic (holophyletic) groups
(i.e. grade = clade)
Symplesiomorphy -> paraphyletic groups
ex. reptiles and fish
convergence -> polyphyletic groups
80
Autapomorphies
derived trait unique to a group
81
Phylogenetic systematics
- taxa (clades_ defined by shared derived traits only
- evolutionary relationships (phylogeny) among taxa represented by a branching diagram (cladogram)
- sister clades receive equal rank (no taxon labels)
* * more than 2 branches = polytomies
- all taxa are monophyletic
- groups defined by shared ancestral traits have no taxonomic value, but still may be important in other ways (ecology, physiology)
82
The Fossil Problem
- incomplete specimens
- incomplete record through time
- mostly hard parts, soft tissues
- no molecular data
- maybe unique derived traits that we cannot see
83
3 kinds of clades
- node-based (e.g. "crown" group)
* based on extant forms
- stem-based ("total" group)
* consists of crown group plus extinct forms that are part of the ancestral lineage of the crown group
- apomorphine-based
* based on first known appearance of a particular derived trait
84
Isomorphy
similarity in organisms of different ancestry resulting from evolutionary convergence
85
Occam's Razor
Parsimony
being miserly in use of assumptions
--> most plausible and simple hypothesis possible
In phylogeny construction, csadorgramwith the fewest evolutionary steps Is the best starting point
86
Ingroup
group of taxa whose relationships we want to resolve
87
Outgroup
a comparison taxon closely related to the taxa of interest; l sometimes two (or more) outgrip taxa are used, one more closely related to the in-group and one more distantly related
used to determine the polarity (direction) of changes in traits
88
Jukes and Cantor
attempts to correct unobserved changes in DNA sequences
**distantly related sequences have likely experience more substitutions than visible
distance = -(3/4)ln(1-1(1/3)p)
p=p-distance
89
orthologs
genes in different species that evolved from a common ancestral gene by speciation
- normally retain the same function in the course of evolution
90
Paralogs
genes related by duplication within a genome
**orthologs retain the same function in the course of evolution whereas parlous evolve new functions, even if these are related to the original one
91
Atavisms definition
- resemblance to remote ancestors rather than to parents in plants and animals
- reversion to an earlier type
Opposes Dollo's Law (evolution is not substantively reversible and genetic information an degrade or become nonfunctional)
92
Atavism in animals
trait present in ancestor but dormant in species until resurgence or reapparition of trait
93
Lineage specific events
shared history
| similar to one another due to shared history, therefore not really independent data points
94
Pseudoreplication
when you think you have independent replication points but you don't because they're from the same unit
(regression will therefore be less strong because less data points)
95
Edentulous
lacks teeth
96
Rhamphotheca
beak, used to pick up and manipulate food
97
Gizzard
muscular chamber for the stomach, used by birds to grind up food and aid in digestion
98
Gastroliths
bird who swallows rocks
aids in digestion
**no living birds have teeth but ancestrally some did
99
aposematic colouration
colour thought to advertise toxicity
| to potential predators
100
adaptive radiation
```
process in which organisms diversify from ancestral species into a multitude of new forms
Due to:
- change in environment
- new resources
- new challenges
- new niches
```
Speciation from recent single ancestor and phenotypic adaptation of an array of species demonstrating diff. morphological and physical traits
101
ecomorphs
species with same structural habitat/niche, similar in morphology and behaviour but not necessarily close phyletically
small difference in form or colour that distinguishes populations of a species that have recently become reproductively isolated
adaptations = local environmental variations
102
Gastrulation
Coordinated celle movements and rearrangements
Generates 3 germ layers:
ectoderm - skin, NS
Mesoderm - muscle, bone
Endoderm - gut
In protostomes starts at mouth
In deuterostomes starts at anus
103
Blastopore
future anus
104
Neurulation
Dorsal ectoderm becomes central nervous system
105
Neural tube formation
forms the entire nervous system
defects from failure of closure (ex. spina bifida)
106
Notochord
defining structure of chordates
contributes to nucleus pulposus in fully formed intervertebral discs
In dev: provides signals that pattern the overlying CNS
107
Amnion
secretes fluid
108
Allantois
- stores waste
| - gas exchange
109
Chorion
- outermost membrane
- gas exchange
- mammals = placenta
110
Yolk sac
- nutrition (birds and reptiles)
111
Polyembryony
more than one embryo from one egg
| - share one chorion and one amnion
112
Macroevolutionary phenomena
- origin of new structures
- discontinuities in "adaptive space"
- rates of evolution
- causes and natures of radiations
- causes and natures of mass extinctions
113
Preadaptation
particular structure and function now
| but could evolve into something else in the future, cannot know though
114
Exaptation (co-option)
genes can be co-opted
| acquisition of function by features for which they were not originally intended
115
Key traits for fitness
body size (and growth) has impacts on:
- physiology
- attainment of sexual maturity
- fecundity
- generation time
- population dynamics
* especially in ectotherms
116
Pseudogenation
non-functional or disappears
| no consequences
117
Sub-functionalization
two copies split the functions of the original gene
118
Neo-functionalization
the two different copies take on different functions
119
Neoteny
| or paedomorphosis
retention of larval/juvenile traits
120
"obligate" paedomorphosis
- occurs in species which metamorphose
ex. reproductively mature when still in juvenile state
paedomorphosis
121
"facultative" paedomorphosis
Phenotypic plasticity
- may or may not metamorphose, depends on environment
- environment/external conditions dictate metamorphoses
paedotypy
122
Peramorphosis
phylogenetic change in which individuals of a species mature past adulthood and take unseen traits
- can also be delayed maturity and extended adult development
123
Recruitment
stage of life where variability and life history is determined
(inter annual variability of individuals that survive the larval stage)
FISH!
124
Reynolds Number (Re)
```
relative importance of viscous and inertial forces on a moving object
Re = UL/v
U=swim speed
L=body length (m)
v =kinematic viscosity of seawater
```
Re<100 viscous forces dominate
Re>200 inertial forces begin to dominate
125
Changes associated with fish metamorphosis
- switch from cutaneous to gill breathing
- development of paired pectoral fins and tail
- development of adult-like pigmentation
- switch frkomeel-like swimming to "beat and glide" swimming
- eye migration in flatfish
- development of vertebrae increases body rigidity for swimming
126
Conceptual relationships of evolutionary mechanisms
- Phenotypic plasticity shaped by developmental process
- natural results in evolutionary mechanism
- genetic assimilation or accommodation results in evolutionary outcome
127
Epigenetic modifications
chromatin and DNA modifications that influence genome function but do not change the underlying DNA sequence
*gene is modified but not changed in constitution
128
DNA methylation
the addition of methyl groups, usually to a cytosine base, as a means of chemical DNA modification [most extensively characterized epigenetic mechanism in eukaryotes]
129
Vestigial genes
dead/silenced genes
pseudogenes
humans have 30 000 genes, more than 2000 pseudogenes that do "nothing"
130
Vestigial organs
organs we retain but they have little or no important function for us anymore
131
Homeostasis
operates by negative feedback
| = stabilizing
132
Symmorphosis
The state of structural design resulting from morphogenesis regulated to functional demand.
** if the functional requirements of an organ system vary, the structural design should vary in parallel
133
Function of epithelial tissue
- protection
- transport
- secretion
- absorption of nutrients released by digestion of food
134
Function of connective tissue
- Structural support
135
Function of muscle tissue
- movement
136
Function of nervous tissue
- communication
- coordination
- control
137
Coelom
body cavity
| most organs of the body are contained in the coelom
138
Functions of the integument
- protection against mechanical injury and microbial infection
* *skin is the interface with the environment, first line of protection against injury
- regulation of water content of the body
- regulation of body temperature
* *insulation, fur, feathers, subcutaneous fat
- attraction of mates and other social interactions
* *size & colour of feathers, fish use colour as sexual attraction, glands in skin for pheromones, sexual display and courtmanship, sexual dichromatism
- excretion/elimination of wastes
- respiratory gas exchange
- muscle attachment
- sensory
* temp, touch, pain, pressure
- protection against predators
139
Sweat
cools
eliminates salts, some urea and toxins
- hippos excrete red sweat that also acts as antibiotic sunscreen
140
Integument
Epidermis (on top)
--> from ectoderm
Dermis
--> from mesoderm
Amphioxus - think skin, one layer of epidermal cells, covered by cuticle
Tunicates
- thin epidermis, which secretes a thick tunic (cellulose-like) in sessile adults
141
Cuticle
an acellular layer on the skin surface of a fish formed by secretions from epithelial cells, goblet cells, and other cells in the epidermis. The cuticle may contain a variety of protective substances including toxins and antimicrobial compounds
142
Dermis
layers:
stratum spongiosum
stratum compact
hypodermis
Produces:
- collagenous & elastic fibres
- fibroblasts
- bones & scales
- nerve fibres
- blood vessels
- smooth muscle
- chromatophores
143
Dermal/membrane bone
intramembranous ossification
EXOSKELETON
-> includes dermatocranium
144
Edochondral bone
endochondral ossification
ENDOSKELETON
bone produced in cartilage, cartilage precursor
145
Nociceptors
pain
146
pruriceptors
itch
147
thermoreceptors
heat
148
mechanoreceptors
touch
149
Hairy vs. glabrous skin
Glabrous = hairless
affective vs. discriminative touch
150
Mystacial pads, vibrissae
Vibrotactility, navigation & spatial orientation in the dark
extends sensitivity beyond surface of skin
151
Epidermis
```
Epithelial tissue, outer layer
Components:
stratum corneum
stratum germinativum
keratinocytes --> produces keratin add responsible for waterproofing
```
regular loss of outer cells
snakes lose all at once
humans continually lose
152
Keratinized derivatives of epidermis
- calluses (also involve dermis)
- foot pads in mammals
- friction ridges in primates
- scutes/scales in squamate reptiles (includes rattle), legs of birds, tails of many mammals (whole body of pangolin)
- beak or bill in birds, turtles & monotremes
- claws, nails & hooves
- horns & antlers in mammals (some include bone)
- feathers in birds
- hair/fur in mammals
- bony scutes
153
Feathers
- derived from reptile scales/scutes
- function as insulation for thermoregulation & flight
- usually pigmented but colour also due to reflection
- complex hierarchical structure
- moulted periodically
- 6 basic types:
down, contour (includes flight feathers on wings and tail for lift)
154
Hair
- not modified scales but new structures
- root of living cells produce new hair
- root associated with sebaceous gland & erector muscle
- pigmented, but also some structural colour
- moulted periodically
- varied forms among species and on different parts of body
2 layers
- dense undercoat (insulation)
- outer coat of coarse hairs (guard hairs - various functions, including behaviour, protection from rain)
Variations: wool, porcupine quills, hedgehog spines, rhino horns (N.B. not all horns = modified hair, all horns related and modified keratin but different forms)
155
Function of sebaceous glands
lubricate the hair and skin
156
Epidermal glands
- mucous glands
**abundant in fish, antibacterial properties, protects from pathogens, keeps skin moist, provide means for skin gas exchange
- poison glands
- scent glands
- sweat glands
- sebaceous glands
*associated with roots of hairs
- mammary glands
*nipple = many ducts
teat = single duct
- uropygial glands
157
Scales in fish vs. reptiles
Teleost fish have scales (bony) from dermis
Reptiles have epidermal scales formed from keratin
158
Scute
external bony plate capped by keratin
(ex. turtle shell, osteoderms of crocodilians, body armour of armadillo)
Both dermal and epidermal parts (dermal bone w/ epidermal keratin)
159
Sturgeons
do not have body scales but have 5 rows of scutes
made of bony plate but no keratin
160
Colour
In ectotherms + hair and feather free skin of endotherms, colour due to chromatophores (derived from neural crest) in the DERMIS:
1) melanophores
2) lophophores (xanthophores & erythrophores) -> yellows
3) iridophores -> red, reflects colour
4) cyanophores -> blue (2 species of fish)
In birds & mammals, feathers and hair are pigmented (melanins, carotenoids, etc.) but can be structural
dispersal of melanin = darker
concentration of melanin = paler
161
Time of flight secondary mass spectrometry (ToF-SIMS)
composition & spatial distribution of surface molecules
| including comparisons with spectra of melanin
162
Scanning Electron Microscopy (SEM)
presence of ovoid bodies consistent with melanophores
163
Energy-dispersive X-ray (EDX) microanalysis
carbon associated with skin and not adjacent sediment
164
Colour change
- shifts in relative position of chromatophores
- changes in distribution of pigment granules within chromatophores
- seasonal moult of plumage (birds) or pelage (mammals)
* *ex. nuptial colouration (seasonal dichromatism)
- ontogenetic change
165
Skeletal materials of the skeletomuscular system
- internal, jointed skeleton of bone or cartilage
- support of body
- movement (including locomotion) via joints
- enclosure and protection of vital organs (heart + lungs protected by ribs, brain protected by cranium)
- storage of minerals
- assistance in lung ventilation in amniotes
*notochord important signalling center
mineralized skeleton regulated mineral metabolism and hormones
takes part in sound reception
166
Important connective tissues
- cartilage
- bone
- ligaments
- tendons
(muscle) not considered a connective tissue but important in connective structures
167
Cartilage
- matrix
- collagen
- chondroblasts
- chondrocytes
- lacuna(e)
168
Endoskeleton + cartilage
endoskeleton initially formed from cartilage but is replaced by endochondral bone
169
3 types of cartilage
Hyaline: "temporary" cartilage during growth; most articulations, ribs, nose, larynx
Fibrocartilage: intervertebral discs, other joints
Elastic - pinna, epiglottis, other parts of visceral skeleton
170
Bone
- support & locomotion --> balance between stiffness (hardness) and toughness (strength)
- organic components (collagen) - toughness and elasticity, resistance to tensile loads
- mineral components (e.g. hydroxyapatite) - stiffness, resistance to compressive loads
Hydroxyapatite: hard tissues with calcium phosphate (enamel)
dynamic = modelling & remodelling, resorption & deposition
Compact (cortical) vs. spongy (cancellous, trabecular) bone
stiffness - toughness tradeoff
171
two morphological components of bone
Cortical: envelops entire structure
Cancellous/trabecular: typically found towards end of bone
*internal space filled with marrow
172
Direct (membranous) ossification
dermal armour, dermatocranium, parts of visceral skeleton, clavicle, others
173
Indirect (endochondral) ossification
most of axial and appendicular skeleton
174
Heterotopic bones
isolated bones formed outside the skeleton proper
175
Sesamoid bones
small bones found associated with tendons or joints
176
Medullary Bone
Secondary bone - birds only; present only in pre-laying and egg-laying season
in marrow cavities of long bones and some others
macroscopically similar to cancellous bone
histologically non-structural woven bone
highly vascularized, high surface area, high mineral: collagen ration -> supplies 40%+ of Ca for eggshells
177
LIgaments
holds bones together and provide support
178
Endoskeleton
Cartilage bone: vertebrae, ribs, limb bones
Membrane bone: centra of teleosts, sesamoid, orbitosphenoid of Amphisbaenia
179
Exoskeleton
dermal bone: skull roof bones, denture, clavicle, gastrula, scale of fishes, osteoderm
180
Axial skeleton
Braincase, vertebral column, ribs
Vertebral column (backbone and tail):
- made up of articulating vertebrae
- first vert. (atlas) articulates with occipital condyles on back of braincase; in amniotes, second vert. is also specialized (axis)
181
Mammal regionalization of vertebral column
```
Cervical
Thoracic
Lumbar
Sacral
Caudal
```
182
oviparity
release of an unfertilized egg or an undeveloped (or incompletely developed) zygote/embryo. Thus, this includes both ovuliparity and zygoparity
183
Viviparity
release of a “fully” developed offspring. This is essentially embryoparity for some, but others restrict the latter to oviparous species with extended egg retention
184
3 types of fertilization
- cloacal apposition ("cloacal kiss")
some anoraks, tuataras, most birds
- spermatophore
salamanders
- copulation via male intromittent organ
185
Ribs
- tetrapod ribs are homologous with dorsal ribs of fish
- protects organs
- important attachment - points for muscles
- breathing
- modified in various groups (ex. turtle shell)
- rib reduction or loss (anoraks) vs. many ribs (snakes)
- attached to sternum ventrally in tetrapods
186
Appendicular skeleton
- limbs (pectoral & pelvic = anterior & posterior) + supporting pec & pelv girdles
- homologies between bones of pectoral girdles of fish and tetrapods uncertain
- pelvic girdle firmly attached to sacrum in tetrapods (thrust), bot not in fish (attached to sacrum)
- pectoral girdle firmly attached to head in fished but not in tetrapods
* *pectoral girdle often not attached to vert. column except in brachiators and flyers (Clavicle)
187
Clavicle
- present in fish and tetrapods (circular or wishbone in birds but homology uncertain); lost in some groups (snakes)
- the only dermal element left in pectoral girdle of mammals
- variably present in mammals (e.g. humans - braces should, reduced in cats, absent in rudimentary most other carnivores)
188
Functions of digits in tetrapods
- support
- locomotion
- digging
- grasping
* *perching, climbing, food manipulation
189
types of joints
- immoveable (synarthrosis)
- slightly moveable (amphiarthroses; symphysis)
- freely moveable (diarthroses; synovial joint)
* subtypes: hinge joints, ball & socket, etc.
190
Stridulation
rubbing or scraping together of fins, bones or teeth
| how fish make sound
191
Air passage
internal movement of air or escape of air through mouth, gills or anus
for producing fish sounds
192
Drumming
special muscles pushing/pulling on the internal air/swim bladder
*sonic muscles
producing sound in fish
193
when are fish vocal
- spawning and courtship
- aggression and territorial behaviour
- distress
- predator/prey behaviour
194
how to listen to fish sounds
passive acoustics
- non-invasive
- non-visual (no light needed)
- continuous remote monitoring
- detailed behavioural information
195
Skull parts
Chondocranium (braincase) - somatic
Splanchnocranium (visceral skeleton) - branchial arches
Dermatocranium (skull roof) - dermal
196
Jaw suspensions
Amphistyly - mandibular arch supported in part by hyomandibula (primitive Chondrichthyes).
•Hyostyly - mandibular arch supported primarily by hyomandibula
(typical Chondrichthyes, Actinopterygia).
•Autostyly - mandibular arch not supported by hyomandibula (Dipnoi, Tetrapoda); craniostyly in Mammalia.
•Streptostyly – quadrate bone moveable (Lepidosauria, Aves).
197
Teeth in mammals
specialized
| teeth restricted to premaxilla, maxillae and dentary
198
Palate
gives skull strength and resistance to tortion
199
Temporal fenestration in amniotes
refers to openings in the side of the skull (temporal)
fenestration = openings
long been a classification basis
opening low on side of skull = synapsid (mammal) condition
200
Functions of temporal fenestrae
- Reduction of skull mass without sacrificing strength
- additional attachment area for jaw-closing musculature
- room for large jaw-closing muscles to bulge outward in contraction
201
Post orbital bar
absent in most mammals, can be found in horses
202
Cranial kinesis & strepostyly in squamates
ability to skull roof to move relative to braincase
seen in reptiles, birds, fish, not really mammals
Metakinesis and Mesokinesis typically seen with lizards
snakes and birds show prokinesis
203
Streptostyly
reduce stress through soft tissues
| free quadrate to move back and forth
204
Propalineal feeding
opening = jaw moves down and backwards
| allows for breakdown of food
205
Functions of muscular system
- movement of body and its parts
- support and posture (tonus)
- protection of joints
- internal transport
- homeostatic adjustments
- protein storage
206
Smooth muscle
```
not striated
spindle shaped
not branched
nucleus central
no disks
involuntary
```
207
Skeletal muscle
```
striated
cylindrical
not branched
nuclei peripheral
no disks
voluntary
main mass of muscle in body = controlled
```
208
Cardiac muscle
```
striated
cylindrical
branched
nuclei central
intercalated disks
involuntary
does not fatigue
branching patter allows propagation if contraction across whole muscle
```
209
Skeletal muscle
it goes Actin, z band, myosin, z band, actin
| contraction shortens sarcomere length
210
Isotonic
contraction leads to change of muscle length against constant load or force
does work
211
Concentric (sub of isotonic)
muscle shortens as it contracts (i.e. force generated by muscle sufficient to overcome the resistance of the load)
212
Eccentric (sub of isotonic)
muscle lengthens as it contracts (i.e. force insufficient to overcome resistance of load)
213
Isometric
contracted muscle does not change length
force and load = balanced
supports loads or maintains posture
214
force and speed production of muscle
depends on
resting length
cross-sectional area
velocity
tradeoff = faster produces less force and vice versa
speed of contraction depends on muscle configuration and proportion of red and white fibres
longer muscle can shorten more than shorter muscle
215
Parallel fibres muscels
ex bicep
some contract up to 50% of length
fibres parallel to long axis of muscle and generate all their force in that direction
216
Pennate muscles
ex masseter
fibres at an angle to the muscle's force-generating axis, less efficient
fibres shorter but more fibres cross-sectionally (more force in small space)
217
Categories of Muscle Function
Extensor vs. Flexor
Adductor (to) vs. Abductor (from)
Levator vs. Depressor
Rotator (e.g. Pronator (inside) vs. Supinator (outside)) Sphincter (vs. Dilator)
218
Fast-twitch (white) fibres
high force, rapid fatigue, glycogen, anaerobic
219
Slow-twitch (red) fibres
low force, fatigue-resistant, mitochondria, myoglobin, aerobic
220
Hard skeleton
- internal jointed skeleton of vertebrates (bone and/or cartilage)
- external jointed skeleton of arthropods (chitin)
- external skeleton (test) of echinoderms (calcareous ossicles - either fused or jointed)
221
Hydrostatic skeleton
- fibre-reinforce container around a fluid-filled cavity (e.g. earthworms)
222
Muscular hydrostat
A muscular organ lacking a distinct skeletal system, but capable of varied and complex movements.
ex. tongue, elephant trunks, tentacles
223
Poikilothermy
body temp varies
224
homeothermy
body temp more or less consistent
