Long Exam 2 Flashcards
evolved sometime during the Cambrian period, 500 million years ago during the Cambrian explosion, almost at the same time when invertebrates began to develop
Chordates
May have evolved from some freshwater forms as all modern _____ possess glomerular kidneys designed to remove excess water from the body
Chordates
Early fossils of these have been all recovered from marine sediments and even modern protochordate are all marine forms
Chordates
also found in marine forms such as myxinods and sharks
glomerular kidneys
hagfish class Myxini, jawless, boneless, and sightless fish that exhibit unique behavors
myxinods
chordates evolved from them, includes echinoderms, hemichordates, pogonophrans, etc.
deuterostome
fossils of the earliest vertebrates were known from its, about 400 mya
Silurian-Devonian Period
do not have eyes, ears, and jaws but are considered an important organism in studying chordates
Amphioxus
precursor of a backbone, humans carry a vestiges of these (disk in the spine)
Notochord
first mammals with bony jaws
fish
with this happening, organisms become bigger
four fold increase in genes
a group of marine animals that spend most of their lives attached to docks, rocks or the undersides of boats
tunicate
are semi-transparent barrel-shaped marine animals that move through the water by contracting bands of muscles which ring the body
salp
porous walls of its home allow food particles to flow into an inner chamber where this blue, wispy animal feeds
larvacean
showed how reptiles sporting innovations like jaws and legs flourished on land
monitor lizards
origin theory given by Johannes Muller on 1860 based on comparative studies of larval stages of echinoderms and hemichordates
echinoderm origin
resembles echinoderm larvae such as Bipinnaria, Auricularia, Dipleurula, and Doliolaria, which possess ciliary bands and an apical tuft of cilia
Tornaria larva
proposed that echinoderm larvae gave rise to chordates by neoteny
Johannes Muller
W. Garstang
DeBeers
are deuterostomes and possess mesodermal skeletal elements
Echinoderms
fossil echinoderms discovered from the Ordovician period (450 mya)
Calcichordata
Asymmetrical animals that demonstrate affinities with both echinoderms and chordates but their skeleton is made up of CaCO3
calcichordata
Have large pharynx with series of gill slits, each covered with flaps for filter feeding, a small segmented body, and postanal tail
calcichordata
functions for filter-feeding appears to have evolved in diverse groups of animals during the Cambrian-Ordovician periods
perforated pharynx
bones are made up of hydrated calcium and phosphate
vertebrates
suggested by Romer in 1959 wherein ancestral deuterostomes were sedentary tentacle feeders whose mucous-laden ciliated tentacles served to trap planktons as they were waved in water as do the modern lophophorates and pterobranch
hemichordates, Cephalodiscus and Rhabdopleura
hemichordate origin
Pharyngeal slits evolved in this ancestors, which made pharynx sieve-like to trap planktons as the water current passed through it
hemichordate
possess both ciliated arms and pharyngeal gill slits
pretobranch
W. Garstand (1928) and N.J. Berill (1955) – gave importance to the tadpole-like larva or urochordates which carries typical chordate characters, namely, a notochord in tail along with segmented myotomes, dorsal hollow nerve cord, sense organs, and pharyngeal gill slits
Urochordate origin
suggested that chordates evolved from some sessile filter-feeding urochordate by the larval stage evolving into adulthood by neoteny and by losing the sedentary adult stage
Garstang
Chamberlain studies the primitive and advanced characteristics of cephalochordates and proposed that while extant cephalochordates possess all chordate characters in a typical state, they also show some primitive features of non-chordates, such as the absence of heart, head, sense organs, respiratory pigment, filter
-feeding mode of food capture and excretion by solenocytes
Cephalochordate origin
earliest chordate whose fossil have been discovered from Burgess Shale in British Columbia, Canada.
Pikaia gracilens
show a streamlined, ribbon-shaped, 5 cm long body having notochord in the posterior two-thirds of the body and myomeres
Amphioxus
combined all above theories of echinoderm, urochordata, cephalochordate origins and proposed that the common ancestor of echinoderms and chordates was a sessile ciliary arm feeder that lived in the plankton-rich environment of the Cambria
Combined theory of E.J.W Barriton
modern version of these have evolved from similar ancestors by retaining the original mode of feeding
Echinodermata
perforation of the pharynx with gill slits, must have evolved in a large number of groups which have been a much superior method of food gathering by filtering water as compared to ciliated arm feeding
pharyngothremy
marine animals and lack a bony or cartilaginous skeleton; suspension feeders
cephalochordates and urochordates
have an endoskeleton and some are terrestrial and most use jaws to feed
vertebrates
Four basic characteristics of phylum chordata at some time in their history:
notochord
dorsal hollow nerve cord
pharyngeal slits
post anal tail
dorsal supporting rod
notochord
Replaced by a vertebral column in adult vertebrates (anlagen/precursor of the vertebral column)
notochord
in contrast to invertebrates having a ventral solid nerve cord
dorsal hollow nerve cord
have a hollow nerve cord meaning that the cord contains a canal that is filled with fluid
vertebrates
humans have this fluid in their hollow nerve cord
central canal cerebrospinal fluid
persist in adult fishes, but in most vertebrates are only seen during embryological development
pharyngeal slits
Water passes into the mouth and the pharynx going through here, which are supported by gill bars and used for gas exchange
pharyngeal slits
represents a posterior elongation of the boy extending beyond the anus
post anal tail
Extension of the chordate locomotor organ, the segmental musculature, and notochord
post anal tail
study of the development of embryos from fertilization until they become fetuses or at point which you can distinguish the species
embryology
comparison of embryo development across species
comparative embryology
all embryos pass from single cells to multicelled what
zygotes
clumps of cells
morula
hollow balls of cells
blastula
The process of embryogenesis begins with an ____ or ovum being fertilized by a ____ cell to form a zygote
egg
sperm
zygote is surrounded by a strong membrane made up of this, which the sperm has managed to penetrate
glycoproteins
formed 24 hours after the egg and sperm nuclei fuse
zygote
Over the next three days, the zygote undergoes a number of cell divisions, a process referred to as _____
cleavage
process once the embryo has reached 8-celled stage, involves the tight binding of the cells to create a compact shere
compaction
16-celled embryo that the embryo turns after compaction
Morula
cavity that developed in the morula after one day of compaction
Blastocele
structure that formed after the cells inside the blastocele compact and flatten
Blastocyst
moves towards the womb, where it implants itself in the lining after 24 hours
Blastocyst
Over the next week, the mass of cells rapidly divides, giving rise to a disc-shaped structure that has two layers:
animal pole
vegetal pole
layer becomes the embryo and amniotic cavity
animal pole
layer develops into the yolk sac
vegetal pole
occurs where the blood system starts to appear in the placenta and blood cells are produced by the yok sac, a streak of cells becomes apparent on the embryonic disc
Gastrulation
study of development from fertilization to embryo
embryology
Reveals ancestry
embryology
Nature of relationship from ancestor to offspring can be studied
embryology
ontogeny recapitulates phylogeny.”
who said?
Ernst Haeckel:
Recapitulation is not only relationship between embryos and ancestors”
Gavin De Beer
according to De Beers, these may or may not be present from their ancestors or descendants
embryonic structures
Can be lost (vestigial) or retained to adulthood
embryonic structures
may be repeated in earlier stages but not in later stages
developmental stages
may or may not be altered in the descendant
developmental sequences
sex cells, haploid chromosomes that unite to form diploid organism
gametes
Perform meiotic division
gametes
gametes for males, have various head appearance such
sperm
head apperance of sperm (7)
spherical
spatulate
hooked
lancet-shaped
spiraled
capped (acrosome)
used for movement in sperms
tail
part of the sperm that contains digestive enzymes
acrosome
part of the sperm that contains 23 chromosomes
nucleus
part of the sperm cell that contains many mitochondria
collar
causes sperm to swim
flagellum
are made up of microlecithal (small yolk), mesolecithal (moderate yolk), and
macrolecithal (abundant yolk)
egg cell
small yolk in egg cell
microlecithal
moderate yolk in egg cell
mesolecithal
abundant yolk in egg cell
macrolecithal
process of formation of gametes i.e. sperms and
ovary from the primary sex organs in
all sexually reproducing organisms
gametogenesis
plays most significant role in the process of gametogenesis
meiosis
spermatogenesis formula
1:2:4
differentiation of an ovum into a cell competent to further develop when fertilized
oogenesis
developed from the primary oocyte by maturation
ovum
Initiated in the embryonic stage
oogenesis
Primary oocyte in oogenesis count of chromosomes
46/2N
secondary oocyte in oogenesis count of chromosomes
23/1n
oogonium count of chromosomes
46, 2N
ootid count of chromosomes
23, 1N
a cell in ovary which may undergo meiotic division to form an ovum
oocyte
Immature egg cell that will eventually break free from the follicle and travel down the fallopian tube – at which point it’s called an egg or ovum
oocyte
single cell released from either of the female reproductive organs, the ovaries, which is capable of dev
eloping into a new organism when fertilized (united) with a sperm cell
ovum
developed and released by ovarian follicle
oocyte
surrounds and nourishes the egg
vitelline membrane
in therian mammals, egg is enclosed in this along with corona radiata, cells of ovarian follicle
zona pellucida
present in amphioxus; eutherian mammals (egg yolk)
microlecithal
of, relating to, or belonging to the Eutheria, a subclass of mammals all of which have a placenta and reach an advanced state of development before birth.
eutherian
egg yolk present in lampreys; some fishes; amphibians
mesolecithal
egg yolk present in most fishes; reptiles; birds; monotremes (egg-laying mammals)
macrolecithal
Egg is enclosed after ovulation in jelly layer in what group of animals
amphibians
Egg is enclosed after ovulation in albumen in what group of animals
birds
Egg is enclosed after ovulation in horny, membranous in what animals
fishes
Egg is enclosed after ovulation in calcareous shells in what group of animals
reptiles, birds
Most animals proceed through these stages during development (5)
zygote
early cleavage stages
gastrulation
segmentation (inc. neurulation)
organogenesis
establish polarity and body axes
blasutla
where germ layers are established
gastrulation
this involves neurulation
segmentation
in therian mammals, penetration of sperm from corona radiata to vitelline membrane of the egg
fertilzation
Involves enzymatic and physical interactions between sperm acrosome and egg cortex
fertilization
when this happens the diploid # of chromosomes are restored
union of gametes
hollow sphere of cells produced during the development of an embryo by repeated cleavage of a fertilized egg
vertebrate blastula
epithelial covering layer in blastula
blastoderm
fluid-filled cavity of the blastula
blastocoel
daughter cells
blastomeres
Composed of single tissue layer with hundred of cells
blastula
nutrition of developing embryo; process of cleaving & blastula is dependent on the yolk present
yolk
multiple numbered cells ready for uterine implantation
morula
Cleavage can be:
▪
2-celled
▪
4-celled
▪
8-celled
▪
16-celled
▪
32-celled stages
epiblast or epimere; developing embryo nourished by the vegetal pole (dorsal cells – ectoderm)
animal pole
hypoblast or hypomere, developing yolk, nourishes the embryo (ventral cells – endoderm)
vegetal pole
” (total cleavage furrows penetrate the entire yolk; equal sized blastomeres)
“holoblastic
characterized by or being incomplete cleavage as a result of the presence of an impeding mass of yolk material
meroblastic
holoblastic types (4)
radial
bilateral
spiral
rotational
meroblastic types (2)
discoidal
superficial
holoblastic; unequal-sized blastomeres in amphibians
mesolecithal
larger blastomeres; nourishes the embryo; slower development
vegetal pole
towards the animal pole
blastocoel
“meroblastic” (partial cleavage); unequal sized blastomeres in birds
macrolecithal
large size yolk mass; too great to be penetrated by cleavage furrow in birds
vegetal pole
relatively small (blastoderm)
animal pole
have a microlecithal; holoblastic; unequal sized blastomeres
mammals
structure formed in the early development of mammals
blastocyst
possesses an inner cell mass (ICM) which subsequently forms the embryo
blastocyst
outer layer of the blastocyts containing cells
trophoblast
surrounded by the trophoblast, a fluid-filled cavity
blastocoel
– trophoblast gives rise to this
placenta
Greek word means “a sprout”
blastos
Greek word means “bladder, capsule)
kystis
formation of three germ layers
gastrulation
epiblast or epimere, developing embryo
animal pole
cells migrate to the interior of the blastula, consequently forming two (in diploblastic animals) or into three (tripoblastic animals
gastrulation
embryo during gastrulation is called
gastrula
infolding of cell sheet into embryo
invagination
inturning of cell sheet over the basal surface of an outer layer
involution
migration of individual cells into the mesoderm
ingresion
splitting or migration of one sheet into two sheets
delamination
expansion of one cell sheet over other cell sheets
epiboly
3 germ layers
ectoderm
mesoderm
endoderm
– from epiblast (animal pole) outer layer
ectoderm
middle layer; mesenchyme
mesoderm
from hypoblast (vegetal pole), innermost layer
endoderm
mesolgea is present in what (diploblastic or tripoblastic)
diploblastic
instead of mesoglea, ___ is present in triploblastic animals
mesoderm
central nervous system, retina and lens, cranial and sensory, ganglia and nerves, pigment cells (melanocytes), head connective tissue, epidermis of skin, hair, mammary glands
from what germ layer?
ectoderm
musculoskeletal system, circulatory system, dermis of skin, connective tissue, urogenital system, heart, blood (lymph cells), and spleen
what layer
mesoderm
gastrointestinal system (gut); stomach, colon, liver, pancreas, urinary bladder, lining of urethra, epithelial parts of trachea, lungs, pharynx, thyroid, parathyroid, intestine
what layer
endoderm
formed where cells are entering the embryo
blastopore
two major group of animals can be distinguished according to the blastopore’s fate:
deuterostome
protostome
anus forms from the blastopore
deuterostome
blastopores develops into mouth
protostome
folds inward toward animal pole, double-walled cup
vegetal pole
body cavity (coelom) in gastrulation
gastrocoel
uppermost layer of cells
ectoderm
primitive gut (yolk) lined by endoderm
archenteron
middle layer formed from dorsolateral outpocketing of archenteron
mesoderm
anlagen of nervous system (primitive), formed from dorsal wall of archenteron
notochord
anlagen of nervous system (primitive), formed from dorsal wall of archenteron
notochord
roof of archenteron, forms the notochord in the midline and somites (series of
paired mesodermal tissue blocks)
chordamesoderm
gut tube. Pouch form
schizocoel
formed by splitting of the hypoblast in the somites
coelom
indirectly filled with maternal fluid and enlarges
blastocoel
flattened inner cell mass forms primitive streak (notochord -> CNS)
blastoderm
forms extraembryonic membranes (fetal membranes) and body of embryo (musculoskeletal and circulatory system); mesenchymal tissue
mesoderm
forms by schizocoel (pouch form)
coelom
inner cell mass + primitive streak
embryoblast
notochord (anlagen of CNS); promotes neurulation
primitive streak
overlaps with gastrulation establishing the central nervous system (CNS)
neurulation
coelom in neurulation
neurocoel
What induces thickening of ectoderm into a neutral plate
chordamesoderm
ectomesenchyme, considered as the 4th germ layer which arise from ectoderm forms cartilage and bones of the head, pharyngeal cartilages; peripheral nerve ganglia, some glandular tissues; melanocytes
neural crest cells
ectodermal cells
neural plate
formed from neural plate; folds of cells that arches and meet at the mid-dorsal line and forms the neural tube
neural folds
– encloses the neurocoel (cavity)
neural tube
anlagen of the dorsal hollow nerve cord
neurocoel
migration of primordial germ cells
organogenesis
establishes the head and tail
holoblastic embryo
– 3 germ layers spread faced down on the uncleaved yolk
Type of embryo
meroblastic embryo
embryo increase in ____ while anchenteron becomes part of the ____ tube
length
gut
enterocoelom (blastopore) becomes anus while the mouth opens anteriorly
schizocoely
____form the lining of the gut
endoderm
major structure formed by dermatome (outer epimere)
skin dermis
major structure formed by middle epimere
muscles
major structure formed by inner epimere
vertebral column
major structure formed by chordamesoderm
notochord
major structure formed by intermediate mesoderm
kidney, urogenital ducts
major structure formed by somatic hypomere
bones
major structure formed by splanchnic hypomere
blood, heart, gut, smooth muscle, visceral perotineum
major structure formed by somatic endoderm
skin epidermis, teeth enamel, stomodeum, proctodeum
major structure formed by neural plate ectoderm
brain, spinal cord
major structure formed by neural plate ectoderm
brain, spinal cord
major structure formed by epidermal placodes
capsules
major structure formed by ectomesenchyme
spinal ganglia, nenurocranium, aortic arches, heart septum
in them, yolk cleaves and directly incorpotaed into somatic cells
amphibians
➢
Yolk supply is limited
➢
No fetal membranes required to sustain larva
➢
Early hatching > larva
➢
Example include caecilian, frogs, newts, salamanders
amphibians
in them, yolk remains uncleaved, eggs are laid in water; yolk sac is the only fetal membrane found
fishes
➢
Yolk sac – formed from 3 germ layers to absorb the yolk into the body
➢
Respiration and excretion are direct contract with environment
fishes
in them, there is a primitive streak, extraembryonic, mesoderm splits, forms extraembryonic coelom, splanchnoleure
reptiles and birds
Splanchnopleure + adjacent yolk ++
yolk sac
– under the shell; near the chorioallantoic membrane
allantois
Respiration, receives excretory wates; absorbs albumen takes some minerals from the shell
allantois
Somatopleure + head fold of amnion =
chorion
amnion
“water bag” contains amniotic fluid that bathes the embryo; cushions the embryo
amnion
nourish their young in uterus, exchange and nutrition of fetus occurs between fetal and maternal bloodstream by placenta
placental mammals
vascularized (blood vessels) supplies nutrition to placenta
yolk sac and allantois
avascular (no blood vessels) cannot support placenta
chorion and amnion
homologous to umbilical circulation (mammals)
allantoic circulation
sac filled with amniotic fluid bathes the fetus; allows the early fetus to move freely and protects the fetus from pressure of maternal abdomen
amnion
collective term for reptiles, birds and mammals because the possess amnion
amniotes
chorion (lies between allantois and uterus) incorporated into the placenta, chorioallantoic membrane
maternal contribution
allantois (in most mammals) as fetus grows, allantois decreases in size
fetal contribution
egg laying mammals, deposit eggs in pouch
protherians
marsupials (pouched mammals) no typical placenta
metatherians
includes the skin and the related structures that cover and protect the bodies of animals
integumentary system
the integument of these group of animals includes shells and exoskeletons as body covering
invertebrates
the integument of these group of animals include skin, scales, feathers, hair, and glands
vertebrates
its integument is made up of skin that includes glands, hair, and nails
human
in humans, this protects the body, prevents, water loss, regulates body temperature, and senses the external environment
skin
Evolutionary adaptations of the integumentary system:
regulation of body temp
excretion of waste materials
vitamin D formation via UV radiation
reception of environmental stimuli
locomotion
movement of nutrients and gas
outer covering of the body of vertebrates
integument
Commonly referred to as skin
integument
Include the mucous membrane lining of the mouth, eyelids, nostrils, and the openings of rectum and urogenital organs
integument
Forms the interface between organisms and the external environment
integument
Integument consists of two layers
epidermis
dermis
between the epidermis and dermis this lies
basal membrane
underlying support where epithelial cells are rested
basement membrane
Demarcates the underlying connective tissue from epithelium
basement membrae
membrane proteins of the epithelial cells are anchored in basal lamina, has two 2 major glycoproteins
basal lamina
▪
Laminin
▪
Type IV collagen
▪
Acts as selectively permeable filter between epidermis and dermis connective tissue
basal lamina
reticular fibers embedded in ground substance that connect the basal lamina with the underlying CT
reticular lamina
*r – layer under the dermis that is made up of very loose connective and adipose tissue
Hypodermis or subcutaneous laye
what is converted to vitamin D in skin
cholesterol
– arises from ectoderm
epidermis
attached to basement membrane, it actively cell divides to replenish the outer periderm
stratum germinativum
Differentiates into stratified layer with mucous or keratin coat on the outer surface (prevent desiccation)
epidermis
origin varies (layer of skin)
dermis
principal origin, from the outer wall of dermomyotome of somites
dermatome
form dermatome that settles under the epidermis, some may have stratum compactum that have diffuse, irregular collagen bundles
connective tissue of dermis
beneath the dermis, forms the fascia composed of loose connective tissue and adipose tissue
hypodermis
provides waterproofing and serves as a barrier to infection
epidermis
serves as a location for appendages of skin
dermis
called the basement membrane
hypodermis
composed of epithelial cells derived from ectoderm
epidermis
Serve as the interface between the organism and environment
epidermis
Made up of stratified squamous layer of epithelial cells
epidermis
in them, epidermis is covered by a thin coat of mucus and contains unicellular glands
aquatic vertebrates
in them, epidermis is covered by a dead, water resistant cornified cells (s. corneum)
terrestrial vertebrates
outermost; composed of dead cells; keratinized
stratum corneum
Keratinized layer of skin responsible for keeping water in the body and keeping other harmful chemical and pathogens out, making skin a natural barrier to infection
stratum corneum
translucent layer, composed of flat, dead and non-nucleated cells
stratum lucidum
– composed of keratohyaline granules
stratum granulosum
prickle cell layer; composed of Langerhans cells
stratum spinosum
inner layer, composed of actively dividing cells
stratum germinativum
90 percent of epidermal cells; produce keratin
keratinocytes
8 percent of epidermal cells; produce melanin
melanocytes
capable of trapping antigen in the skin
langerhans cells
make contact with the ending of a sensory neuron
merkel cells
lies below the epidermis and contains an umber of structures including blood vessels, nerves, hair follicles, smooth muscle, glands, and lymphatic tissue
dermis
Consist of loose connective tissue otherwise called areolar connective tissue – collagen, elastin, and reticular fibers are present
dermis
Provides tensile strength and physiologic support for the interfacing epidermis
dermis
Has an ancient and persistent potential to form bone
dermis
also known as hypodermis, not part of the skin, lies below the dermis
subcutaneous layer
Purpose is to attach the skin to the underlying bone and muscle as well as supplying it with blood vessels and nerves
subcutaneous layer
Consist of loose connective tissue and elastin
hypodermis
main cell types of hypodermis
macrophages
fibroblast
adipocytes
Contains 50 percent of body fat
hypodermis
serves as a padding and insulation for the body
dermis
provides concealing coloration to the integument
chromatophore
Occurs in certain cells in a form of small granules contained in chromatophores (pigment-bearing cells)
chromatophore
Pigment-bearing cells of lower vertebrates, including fish that cater the ability of individual animals to shift body coloration and pattern
chromatophore
color change provides this protection
camouflage
Pigment granules are dispersed = greatest/less amount of color
greatest amount color
Pigment granules are concentrated about the nucleus =
greater/ less amount of color
such as in octopi, have pigments that are attached to muscles in which the brain can control
underwater chromatophore
skin color depends on the background color of this layer of the skin
stratum germinativum
ability to change color, controlled by the endocrine and nervous system
metachromatosis
pigment cell that ranges from yellow, brown, to black
melanophores
Chiefly found in S. basale
melanophores
protects the chromosomes of mitotically active basal cell against light
-induced damaged
melanin
Ectodermal in origin, but are derived exclusively in neural crest of embryo, from where they migrate to all other parts of the body
melanophores
phagocytize pigment as it accumulates them especially when skin is exposed to sun
basal cells
seen where melanin is concentrated in one spot
freckles or mole
not just under the control of light, as hormones produced by the pituitary and the adrenal glands also affect pigmentation
pigmentation
Disease of two ____organs can result in changes of pigmentation of the skin
endocrine
includes carotenoids, xanthophores, and erythropores
lipophores
pigment colored yellow, orange, and red
carotenoids
yellow pigment
xanthophores
red pigment
erythrophores
causes iridescence in vertebrates (fishes)
iridophores and guanophores
Contains guanin (purine) crystals
iridophores
–from s. germinativum (epidermis) comprising of exocrine glands
grandular epithelium
have ducts that directly empties onto the epithelium
exocrine
Type of glands as to composition
unicellular
multicellular
single-celled mucus-secreting glands
unicellular gland
growth of s. germinativum (epidermis) into dermal region
what kind of gland
multicellular gland
example of unicellular gland
goblet cell
elongated, binucleated (in amphibians), secretes mucus and may contain chemicals that stimulates alarm or fea
club cells
secreted by individuals in captivity as warning to others
club cells
secretes mucus in skin (lampreys and other fishes)
granular cells
narrow apical end, wide base (Osteichthyes and Chondrichthyes)
goblet cells
secrete large, membrane-bound toxic products to repel enemies
sacciform
lands with a tube-like shape throughout their length
tubular gland
Types of tubular gland (4)
simple
simple coiled
simple branched
compound tubular
short blind tubes located in the dermis and extend to the surface
tubular gland?
simple tubular
example include thumb pads (anurans) and ceruminous gland
simple tubular
long, narrow tube, coiled distal end located in the dermis, openings are referred to as pores of the
skin
simple coiled
sweat gland is what kind of tubular gland
simple coiled
divides at its distal ends in two or more branches
simple branched
Sweat glands in the axilla
simple branched
consist of varying number of simple tubular glands
compound tubular
mammary gland is an example of
compound tubular
glands with a saclike secretory portion
saccular (alveolar) glands
only one expanded bulb or acinus at the end of the duct
simple saccular
Mucous and poison glands (amphibians)
simple saccular
with several acini arranged along a single excretory duct, with single acinus divided by partitions into several smaller acini
simple branched
a type of sebaceous gland with tubulo-acinar structure and holocrine function, located in the superior and inferior tarsal plates) , sebaceous or oil glands
Meibomian glands
composed of several simple saccular glands called lobules
compound sacular
true glands; not destroyed during secretion
merocrine glands
type of glands as to method of secretion
Holocrine glands
Merocrine glands
Apocrine glands
type of gland as to method of secretion of sweat gland
merocrine
part of the cell is destroyed that go with the secretion
apocrine gland
entire cell goes with the secretion but a new cell is produced to replace it
holocrine gland
Sebaceous or oil gland
type of gland as to secretion
holocrine gland
Apical portion of cells are pinched off and lost during the secretory process, resulting in a product that contains molecular components of the membrane
holocrine gland
Involve the death of the cell as the secretory cell is released and it breaks apart
holocrine gland
– secrete mucus, examples include unicellular gland of aquatic vertebrates and some simple saccular gland of fishes and amphibians
mucous gland
secrete watery substance
serous gland
also known as sudoriferous gland
serous gland
secrete oily substance
sebaceous gland
uropygial gland of birds
what ype of gland
sebaceous gland
ceruminous glands and meibomian glands of humans
sebaceous gland
formed from stratum germinativum, characteristic of terrestrial tetrapods
type of scale
epidermal scales
usually shed and replaced from time to time
epidermal scale
scutes of turtles and snakes
type of scale?
epidermal
mesenchymal origin
type of scale
dermal scale
fishes’ scales
type of scale?
dermal scale
small, thick scales possessed only by Latimeria (lobe-finned fish)
cosmoid scale
thick layer of cosmoid scale
cosmine
thin layer of cosmoid scale
enamel
consist of a basal plate embedded in the dermis with a caudally directed spine projecting to the epidermis
placoid
– part of placoid scale that contains a central pulp cavity for blood vessels, nerve endings, and lymph channels from dermis
spine
plate and spine is made up of what material (placoid)
dentine
covers the spine in placoid scale
enamel
modification include shark teeth; dorsal fin spines
placoid scale
rhomboidal in shape, composed of bones
rhomboid/ganoid
shiny material covering ganoid scales
ganoin
found in gars, sturgeons, paddle fish, red fish, bichirs
type of scale
rhomboid
bony layer is characterized by concentric ridges (growth increments), anterior portion is embedded to the dermis, allow increased flexibility of the body
ctenoid
with comb-like or serrated edges along the rear margins
ctenoid
scale that has a smooth rear margin
teleost or bony fish scales
skin of these organisms is non-keratinized and covered by a mucus cuticle
fish
function of the mucus cuticle in fishes:
➢prevents penetration of bacteria
➢contributes to the laminar flow of water across the surface
➢make fish slippery to predators
➢includes chemicals that are repugnant or toxic to enemies
part of the layer of skin of fishes that is alive and active on body surface, no superficial layer of keratinized cells
epidermis
in fish, mitosis is not restricted to the basal layer
true or false?
true
two types of cells in epidermis in fishes
epidermal cells
specialized unicellular glands
make up stratified epidermis
epidermal cells
connected through junctions containing numerous secretory vesicles that are released to the surface
specialized unicellular glands
in them, the epidermis is composed of stacked layers of numerous epidermal cells containing large granular cells and elongated club cells
hagfish and lampreys
their dermis is organized into regular layers of fibrous connective tissue containing pigment cells
hagfish and lampreys
contain multicellular slime glands (hagfishes
hagfish and lampreys
include a basal layer of cells and stratified epidermal cells above, secretory and club cells occur contributing to the mucous cuticle, there is a larger saciform cell
osetichthyes
Dermis is subdivided into superficial layer of loose connective tissue and deep
layer of dense fibrous tissue
which type of fishes?
Osteichthyes
numerous secretory cells and stratified epidermal cells are present in this organism’s epidermis, there is also chromatophore in the lower part
Chondrichthytes
Dermis composed of elastic and collagen fibers giving the skin strength and prevents it from wrinkling during swimming
Chondrichthytes
also known as goniochromism is the phenomenon of certain surfaces that appear to gradually change color as the angle of view or the angle of illumination changes
Iridescence
guanin (purine crystal); causes iridescence in fishes
Guanophores
its integument can be used as a respiratory surface (cutaneous respiration)
amphibians
Frog, salamander, caecilian, toad, and newt
amphibians
divided into four layers: in amphibians
epidermis
thin allowing cutaneous respiration in amphibians
stratum corneum
four epidermal layers of amphibians
s. basale
s. spinosum
s. granulosum
s. corneum
reach into the lower part for cutaneous respiration
capillary beds
thinner, composed of fibrous connective layer in amphibians, divided into 2 layers:
dermis
two dermal layers in amphibians
stratum spongiosum
stratum compactum
its integument is more adapted to terrestrial existence that amphibians
reptiles
There is extensive keratinization, fewer skin glands
reptiles
Turtle, skink, tortoise, snake, chameleon, lizard, crocodile, gecko
reptiles
reptile epidermis is divided into three layers
s. basale
s. granulosum
s. corneum
where epidermal scales are present in reptiles
stratum corneum
dermal bones located under the epidermal scale are found in crocodiles, some lizards, and some extinct reptiles
dermis
Composed of fibrous connective tissue
dermis
large, plate-like scales modified into crests, spines, or horn-like processes
scutes
shedding of cornified layer of the skin
molting or ecdysis
Usually periodic and complete in snakes and some lizards but often only partial in other species
molting or ecdysis
Dependent upon the health of the snake, the ambient temperature, humidity, and other environmental factors
molting or ecdysis
in molting, duplicates the deeper layer of granulosum and corneum forming new skin
s. basale
temp. layer filled with WBC that isf formed between old and new skin
stratum intermediu
promote the sseparation and loss of the old superficial layer of the skin
WBC
bony plate inside the skin in alligators
osteoderms
in reptiles, are restricted to certain areas of the body, important in reproductive behavior and protection
skin glands
– found along the underside of hindlimbs in thigh region of lizards
femoral glands
open into the cloaca and on to the margins of the lower jaw in crocodiles and in some turtles
scent glands
their integument is adapted to free movement over the muscles
birds
➢
delicate except in exposed areas (leg and feet)
➢
covered and protected by feathers
bird integument
composed of stratum basale, transitional layer, and stratum corneum
epidermis
richly supplied with blood vessels, sensory nerves, and smooth muscles
dermis
highly vascularized dermis in the breast during brooding season
brood patches
secretes lipid and protein products used in preening to make the feathers weather repellent
uropygial gland
located in or on the skull usually in the eyes, nose, or mouth containing secretory tubules which radiate outward from the excretory canal at the center (2), excrete excess salt
salt gland
epidermal growths that form a distinctive outer covering, or plumage, on dinosaurs, both avian (bird) and some non-avian (non-bird) and possibly other archosauromorphs
feathers
maintenance behavior found in birds that involves the use of the beak to position feathers, interlock feather barbules that have become separated, clean plumage, and keep ectoparasites in check
preening
– group of animals that have feathers
aves
modified reptilian scales, formed from the beta-keratin layer of the epidermis
feathers
Long, slender shaft with few barbs at distal end
feathers
part of the feather embedded in skin
quill or calamus
their feathers are unusual in length
peacocks
– very small and have only a very few barbs at their tips, they are believed to have a sensory function, helping birds keep their feathers in order
filoplume
smaller and lack the barbules and their accompanying hooklets so they are not zipped together and do not look as neat
down feathers
Soft and fluffy, Provide most of the insulation to the avian body
down feathers
feather present in Falcon
semiplume
arise from feather tracts or pterylae
contour feather or plumae
hollow quill, embedded in the skin, long shaft
calamus
solid part that bears the vane of the feather
rachis
part of the feather that is broad, flat portion-exposed
vane
Gives avian body outline or contour
vane
contour feather on the wings
flight feathers or remiges
feathers on the tail
retrices
Common in most birds except penguins and ostriches
retrices
part of the bird’s skin that does not have feather
apterylae
with minute feathers or insulation but not for flight or swimming
penguin feathers
derived from the epidermis in beavers
beaver-tail
homologous to fingernails in amniotes
hooves
made of bone
antlers
not bone, do not fall off each year
horns
stratified squamous (keratinized)
epithelial tissue
glue-like layer
basement membrane
dense, fibrous, connective tissue, blood vessel, nerves etc. is present in this layer
connective tissue
layer of superficial fascia, subcutaneous tissue
areolar or adiposte tissue
ectoderm origin
epidermis
mesoderm origin
dermis
elongated, binucleated (amphibians), secretes mucus, may contain chemicals that stimulates alarm or fear
club cells
secretes mucus in skin (lampreys and other fishes)
granular cells
narrow apical end, wide base (Osteichthyes & chonrichthyes), secretes mucus
goblet cells
secrete large, membrane-bound toxic products to repel enemies
sacciform cells
Multicellular exocrine glands can be further divided on branching pattern of ducts:
simple
compound
formed in the s. germinativum, found in terrestrial tetrapods, shed and replaced from time to time (ecdysis)
epidermal cells
derives from dermal bone, dermatome origin
dermal scales
skin of these group of animals are non-keratinized and covered with mucus cuticle
integument of fishes
alive and active on body surface, no superficial layer of dead keratinized cells
epidermis of fishes
more adapted to terrestrial environment, extensive keratinization, fewer skin glands
integument of reptiles
permanent pointed projection on the head of various animals that consist of covering of keratin and other proteins surrounding a core of live bone
horn
single structure composed of bone, cartilage, fibrous tissue, skin, nerves, and blood vessels
antlers
single protrusions without forking, grow throughout the animal’s life and are never shed, made of
bone covered by keratin sheath
horns
extensions of the animal’s skull, made entirely of bone, shed and regrown in a larger size each year
antlers
tip of a toe of a ungulate mammal, strengthened by a thick and horny keratin covering
hooves
amphibians integument undergoes molting or ecdysis because of extensive keratinization
false
which of the ff describes the epidermis of terrestrial vertebrates
unicellular with keratinized epithelium
unicellular with nonkeratinized epithelium
multicellular with keratnizined epithelium
multicellular with nonkeratnized epithelium
multicellular with keratinized
dermis of crocordiles and lizaerds are composed of connective tissues and dermal bone
true or false?
true
cells are epidermal cells that serve as our immune sentinels
langerhans
unicellular gland of aquatic vertebrates
mucous gland
vascular segment of integumentary system is called ___
dermis
reptiles exhibits more keratinized skin with more glands
true or false
false
secretes oil used for preening makes the feather water repellant
uropygial gland
skin of most fish is non-keratinized and covered with mucus cuticle (True/False)
true
sweat gland type of gland as to type of secretion
merocrine
oil gland as to type of secretion
holocrine
mammary gland as to type of secretion
apocrine
match the ff
sebaceous gland
apocrine gland
serous gland
alveolar gland
mucous gland
sweat gland
mammary gland
unicellular gland of aquatic vertebrates
meibomian gland
poison gland
sebaceous - meibomian
apocrine - mammary
serous - sweat
alveolar - poison
mucous - unicellular
why is studying the morphology of bones important
reveals evol trend of vertebrate phylogeny, specific adaptations of vertebrates essentrial fore their survival such as posture and locomotion
Origins & insertions of most skeletal muscles are on
_____ (basis for naming muscles)
bones
reveal various
sizes and courses of cranial nerves (senses)
foramina
Important blood vessels pass also through ____
for nutrient supply
foramina
reveal relative development of the different
structures of the brain.
braincase
housed also in the braincase such as
nasal chambers (choanae), orbits (eye cavity) and otic
(ear) cavities.
sense organs
choanae
nasal chambers
eye cavity
orbits
earcavities
otic
give shape to the body, support body weight
bones
As protective & supportive system, it can be divided
into 2 types
exoskeleton
endoskeleton
external hard covering
exoskeleton
Skin-derived: epidermis gives rise to keratin,
dermis gives rise to bones.
exoskeleton
internal body framework
endoskeleton
Formed from mesoderm, not directly from the
integument
endoskeleton
Skeleton can be divided into:
Cranial
Postcranial
Skull or Cranium
cranal skeleton
otochord, vertebral column, ribs,
sternum
axial skeleton
median fin skeletons
(fishes), pectoral & pelvic girdles, paired fins
skeleton, upper and lower limbs (tetrapods)
appendicular skeleton
calcium source
type of skeleton (composition
Mineralized CT
dentin, enamel, cartilage, bony
mode
Mineralized CT
differentiated into
scleroblasts
Mesenchyme
anlagen of osteoblasts
(bones), chondroblasts (cartilage), odontoblasts
(dentin), ameloblasts (enamel)
scleroblast (blastema)
cells that form new bones and grow and heal existing bones
osteoblast
cells that play an important role in the formation of cartilage
chondroblast
re tall columnar cells located at the periphery of the dental pulp.
odontoblast
cells present only during tooth development that deposit tooth enam
ameloblast
irregularly shaped cells, in semifluid ground substance with reticular fibers, gives rise to all other types of connective tissue
mesenchyme
comprise endoskeleton of higher
vertebrates
special connective tissue
differentiates
into muscle, cartilage or bone develop into either
fibroblasts or osteoblasts
blastema
form collagen
fibroblast
impregnated with calcium and inorganic salts
(30% of bony tissue); calcium hydroxyapatite
crystals (60% of the bone) provide compressive
strength for the bone
matrix
30 percent of bone tissue
calcium and inorganic salts
60 percent of the bone
calcium hydroxyapatite
housed in lacunae with bony matrix
osteoblasts
are a series of tubes around narrow channels formed by lamellae, canals surrounding lamellae
haversian canals
cell that maintains bone tissue
osteocyte
cell that form bone matrix
osteoblast
stem gell in bones
osteogenic cell
resorbs bone
osteoclast
type of bones
hard bone/compact bone
spongy bone
concentric rings of matrix around the haversian canal
lamellae
passage for blood vessels and nerves
haversian canal
structures that contain each osteocyte
lacunae
tiny canals protruding from the lacunae connecting access to haversian canal via lamellae, since the haversian canal allows access to blood vessels for nutrient supply
canaliculi
type of growth since insterstitial growth is inhibited by the presence of rigid matrix, deposition of minerals and inorganic salts
appositional growth
bones are formed in two ways:
intramembranous ossification
endochondral ossification
process by which membrane bones are formed such as bones of the lower jaw, skull, and pectoral girdle
intramembranous ossifiction
ossification in teleost, urodeles, and apodans
intramembranous ossification
process by which bone is
deposited in pre-existing cartilage forming a cartilage
bone or a replacement bone.
endochondral ossification
A model for the formation of endoskeleton in ALL
vertebrates
cartilage
differentiates into
chondroblasts (young cartilage cells) or osteoblasts
(young bone cells)
blastema (mesenchymal cells)
young cartilage cells
chondroblast
young bone cells
osteoblast
housed in lacunae
(spaces) develops into chondrocyte or osteocyte
chondroblasts and osteoblasts
secrete a clear matrix
chondrocytes
where each
daughter cell forms matrix & cartilage grows
instertitial growth
cartilage in the adult body
hyaline
elastic
fibrocartilage
most abundant type of cartilage
hyaline
example of hyaline cartilage
ribs (costal cartilage)
articular surface of bones
larynx
trachea
bronchi
Contains more elastin fibers (cartilage)
elastic cartilage
location of elastic cartilage
external ear
epiglottis
Fibrous attachment in between bones, and
attachment of tendons and ligaments.
(cartilage)
fibrocartilage
fibrocartilagei s present in
invertebral discs
attachment of tendons and ligaments
exoskeleton can be (@)
keratinized exoskeleton
bony exoskeleton
cranial skeleto ncan be (3)
splanchnocranium
chondrocranium
dermatocranium
Cranial skeleton
Jaw
Centra & Vertebral Column
Ribs & Sternum
axial skeleton
Pectoral and Pelvic girdles
Upper and Lower limbs
appendicular skeleton
skeletal framework of a vertebrate head
skull
has a skull consisting of a braincase and cartilages of the tongue
lamprey
skull made of a braincase and isolated upper and lower jaw bars
shark
embryonic component that includes cartilaginous brain case or neurocranium
and cartilaginous capsules of olfactory, optic, and
otic sense organs. The chondrocranium is replaced
by bones in most vertebrates
chondrocranium
is derived from the visceral or pharyngeal skeleton
which is cartilaginous but becomes largely replaced
or invested by bones in higher forms. It provides
support to the gills and forms the jaws and
suspensorium in gnathostomes.
splanchnorcranium
It consists of dermal bones which become attached
to the chondrocranium and splancnocranium in bony
fishes and tetrapoda. A dermatocranium is absent in
cyclostomes, elasmobranchs, and a few higher
fishes because the entire skull is cartilaginous.
dermatocranium
Make up the skeleton of the jaws & gills in fishes &
amphibians
splanchnocranium
establishes a supportive
platform that is joined by the contributions from
Splanchnocranium (green), the epipterygoid.
chondrocranium
gives rise to articular,
quadrate, hyomandibula & hyoid apparatus.
splanchnocranium
encases most of the
chondrocranium together with contributions from
the splanchnocranium
dermatocranium
any small oepning or pore
fenestra
has been the most problematic, partly
because the origin of this condition has long been
debated.
euryapsid
This skull is modified from the ___
condition
diapsid
possess only an upper temporal fenestra, usually
bordered by the parietal, postfrontal, postorbital, and
squamosal. - Ex: Placodonts, nothosaurs, and
plesiosaurs (marine reptiles of the Mesozoic era)
euryapsid
possess single temporal fenestra bordered by the
jugal, postorbital, and squamosal. The quadratojugal
and the parietal occasionally contribute to the edge of
this fenestra. (Ex: mammals, therapsids &
pelycosaurs=fin-backed lizard)
synapsid
this fenestra can be called a lower
temporal fenestra
diapsid
is derived from the most anterior
two pharyngeal arches supporting the gills, and
usually bears numerous teeth
vertebrate jaw
jawless fishes
agnaths
theory that states jaw formed from 1 anterior branchial
arches
serial theory
theory stating mandibular arch - formed from
several adjacent arches (neurocranium)
composite theory
ormed from
epibranchial(premandibular arch) & Epibranchial &
pharyngobranchial(mandibular arch)
palatoquadrate
formed from ceratobranchial
meckel’s cartilage
formed from epi/cerato/
hypobranchial (3rd gill
hyoid arch
jaw attachment with no suspension to the skull
plasteostyly
mandibular
arch suspended by ligaments between
chondrocranium and palatoquadrate; attached
directly to skull but no hyoid arch support.
euautostyly
(primitive sharks, some osteichthyes,
crossopterygians or lobe-finned fish) dual suspension by palatoquadrate and hyomandibula; 2
articulations with hyomandibula.
amphistyly
(modern sharks and actinopterygians):
suspension by hyomandibula; supported by
sympletic bone - provides more mobile upper jaw
hyostyly
(most amphibians, reptiles)
suspension by quadrate bone (ossification of
posterior region of palatoquadrate cartilage).
metautostyly
the ossification of the posterior
part of Meckel’s cartilage.
articular bone
the jaws are mostly dermal
elements. Metautostyly frees up the
hyomandibular for other functions (see below).
tetrapods
Support from quadrate and palatoquadrate bones
metautostyly
entire upper jaw
incorporated into braincase and lower jaw is
suspended. The mammals’ jaws are completely
dermal. The Meckel’s cartilage and palatoquadrate
ossifications are in the middle ear.
craniostyly
in Teleosts; supported also by
the hyomandibula
modified hyostyly
Forms the main axis of the body
axial skeleton
Composed of the notochord, vertebral column, ribs
and the sternum
axial skeleton
The primitive axial skeleton, replaced by the
vertebral column
notochord
Unsegmented and composed of dense fibrous
connective tissue
notochord
The first skeletal element to appear in the embryo of
chordates
notochord
composed of a centrum, one or two
arches and various processes
vertebra
vertebral colum originated from where
notochord
structure of vertebral column that accomodate rib, and lateral process
centrum
head of the rib in v.c.
capitulum
arches in v.c.
neural arch
haemal arch
arch surrounds blood vessels
haemal arch
type of vertebra based on centra:
no centra
aspondyly
type of vertebra
1 centrum
monospondyly
type of vertebra with two centra
diplospondyly
type of vertebra with 5 to 6 centra
polyspondyly
type of vertebra with centra/spine separate
aspidospondyly
type of vertebra with fused centra
holospondyly
type of centra based on shapes
flat ended
concave
type of centra that limit motion, withstand compression
flat-ended
type of centra that permits any direction, vertical and lateral flexion, but prevent rotation
concave
type of centra that is concave, both ends permit any direction
amphiocoelus
type of centra that is concave, convex, permits any direction
procoeous
saddle shaped centrum
heterocoelous
flat-ended; withstand compression
mammals
tail in sharrks
heterocercal tail
tail in lungfishes
diphycercal
tail in teleost
homocercal tail
This foramen is where sciatic nerve passes through
that innervates the lower limbs
obturator foramen
Upright and improved locomotion of mammals is
through well-developed and greater sciatic nerve,
thus this has to increase in size.
obturator formaen
type of gait
plantigrade
digitigrade
unguligrade
- entire sole touches the ground
- primitive type
- humans
humans
- metacarpals & metatarsals with
pads
- elevated wrists & ankles
- reduced thumb
- rabbits; cats
digitigrade
m is a group of organs that originates
from the endodermic cells of the developing embryo. The
organs of the skeletal system (osteo-) is primarily
composed of two (2) types of cells which are
the cartilaginous cells (chondrocytes and
chondroblasts) and calcified cells (osseous cells –
osteocytes, osteoclasts and osteoblasts).
skeletal system
(chondrocytes and
chondroblasts
cartilaginous cells
osseous cells –
osteocytes, osteoclasts and osteoblasts)
calcified skells
Forms an important part of the endoskeleton in ALL VERTEBRATES
cartilage
Organic component is primarily ____, which gives bone great tensile strength
collagen
- Major site of red marrow for production of blood cells.
bone
Plays a role in the metabolism of minerals (calcium and
phosphate)
bones
solid, strong bone that is resistant to bending located along the diaphysis of long bones
compact bone
provide solid structure to the skeltal frame, forms hollow tube called medullary cavity
compact bone
made of many branching, bony plates
compact and spongy bone
reduces the weight of the bone, provides strength to bones especially against forces of compression
spongy bone
highly organized transformation of cartilage to bone
endochondral
appositional periosteal bone formation
intramembranous
retain a cartilaginous neurocranium throughout life
cartilaginous fishes
retain highly cartilaginous neocranium that is covered by membrane bone
bony fishes, lungfishes, and most ganoids
embryonic cartilaginous neurocranium is largely replaced by replacement bone
other bony vertebrates
cartilage surrounding the formaen magnum and replaced as many as four bones
occipital centers
forms basisphenoid bone, presphenoid bone, side walls above basisphenoid and presphenoid form
sphenoid centers
tend to remain cartilaginous and form
ethmoid
cartilaginous otic capsule replaced in lower vertebrates
otic centers
– retain a
chondrocranium throughout life
cartilaginous fishes
retain highly cartilaginous neurocranium
bony fishes, lungfishes, most ganoids
embryonic cartilaginous
neurocranium is largely replaced by bone
tetrapods
primitive skull, has no temporal fenestra, possessed by turtles, and other primitive reptiles
anapsid skull
has two temporal fenestrae, possessed by most members of diapsida including crocodile, birds, and lizards
diapsid skull
derived diapsid
euryapsid skull
one fenestra located in a different place than euryapsid skull
synapsid
composed of dermal bones that overlie the chondrocranium and splanchnocranium
dermatocranium
encircles the external naris forming the snout
facial series
encircles the eye defining the orbit
orbital series
lies behind the orbit completing the posterior wall of the braincase
temporal series
located across the top of skull covering the brain beneath
vault series or roofing bones
dermal bones of primary palate covering the roof of the mouth
palatal series
encases the meckel’s cartilage
mandibular series
ancient chordate structure associated with filter feeding surfaces
splanchnocranium
arises from the neural crest departed from the sides of neural tube and migrate into the walls of the pharynx between successive pharyngeal slits
splanchnocranium
Make up the skeleton of the jaws and gills in Fishes and
Amphibians
splanchnocranium
May remain cartilaginous or become covered by dermal
bone
splanchnocranium
characteristic of jaw attachment of agnathans, none of the arches attach directly to the skull
paleostylic
earliest jawed condition, found in placoderms, and acanthodians
euautostylic
found in early sharks, some osteichthyians and crossopterygians
amphistylic
found imodern bony fishes, mandibular arch is attached to the braincase primarily through hyomandibula with aid of symplectic bone
hyostylic
found in most amphibians, reptiles, and birds, attached to the braincase directly through quadrate bone
metautostylic
found in mammals, entire upper jaw is part of the braincase but lower jaw is dentary bone is suspended from the squamosal bone
craniostylic
composed of centrum, one or two arches, and various processes
vertebra
monospondylous vertebra in which single centrum is separate
stereospondyly
two centra per segment
diplospondyly
diplospondylous vertebra in which approximate equal sized central are separate
embolomerous
centra and spine are separate
aspidospondyly
centra and spines are fusedi nto single bone
holospondyly
holospondylous vertebra with husk shaped centrum usually pierced by notochordal canal
lepospondyly
type of centra based on shapes (5)
amphicoelous
procoelous
opisthocoelous
heterocoelous
acoelous
persistent in adults jawless vertebrates, Placoderms,
Chimaeras, Pleurachants, Dipnoans, Acanthodians, Crossopterygians and
Primitive ray-finned fishes
notochord
have no free caudal vertebrae instead a rodlike urostyle
anurans
are unique in forming bony platelike caps or
epiphyses at the ends of their centra posterior to the first
intervertebral joint
mammals
series of cartilaginous or elongated bony structures served as attachment for the vertebrate extending into the body wall
ribs
meet ventrally with the sternum, consist of two jointed segments
true ribs
vertebral or costal rib
proximal sgement
sternal rib
distal segment
articulate iwth each other but not with sternum
false ribs
do not articulate ventrally
floating ribs
midventral skeletal element that usually articulates with the more anterior thoracic ribs and the pectoral girdle
sternum
occur in all jawless vertebrates
median fins
prevent body from turning around the vertical axis (yawing) and around the longitudinal axis (rolling)
dorsal and anal fins
dorsal and anal fins are supported within the contour of the body by a series of rod-like radials
pterygiophores
if the spine is straight to the tip of the tail
diphycercal
if the spine tilts downwards with longer ventral lobe than dorsal loe
hypocercal
if the spine tilts upward with longer dorsal lobe than ventral lobe
heterocercal
if all the fin membrane is posterior to the spine with equal ventral and dorsal lobe
homocercal
older, larger and more complicated thna pelvic girdle
pectoral girdle
right and left halves fused on the midline forming a U-shaped girdle
pectoral girddle
have a blade-like scapula that is oriented to the spine
birds
membrane bone in therian mammals
clavicle
much enlarged over that of fishes, relatively uniform in basic structure
tetrapods
solid, triangular shaped pelvic girlde with the ilium forming the apex
primitive amphibian
have various shapes patterned after basic plan of labyrinthodonts
reptiles
have large pelvic girdle that is firmly attached to the synsacrum
birds
have a long and expanded ilium extending only forward from the acetabulum
mammals
Bones of the wrist
carpus
bones of ankle
tarsus
collective term for carpal and tarsal bones
podials
forefoot
manus
hindfoot
pes
collective term for metacarpals and metatarsals
metapodials
marrow of long bones produce blood cells, a function not
performed by the skeleton of fishes.
amphibians and higher vertebrates
have limbs positioned far to the sides of the body except some
dinosaurs and mammal-like reptiles which are under body
reptiles
are usually cartilaginous but
* may ossify in lizards
epiphyses
- Phalageal formula in Reptiles
manus and pes
- 3-4-5-3 for manus
- 2-3-4-5-4 for pes
- Phalageal formula of foot in birds
2-3-4-5-0
forms the heelbone or calcaneum
tarsus, fibulare
joins the intermedium forming a large bone called astragalus that
lies over the calcaneum
tibiale
basic pharyngeal formula in mammals
2-3-3-3-3
bones embedded in interrupting tendon
sesamoid bone
example of sesamoid bone
patella
bone in the penis of carnivores, bats, insectivores, ordents, and some priates
baculum
type of locomotion
graviportal
cursorial
volant
aerial
saltatorial
aquatic
fossorial
scansorial
arboreal
familiarize youself with tables
GOODLUCK BEH POTA
