BIO EXAM 3 Lec 10 Flashcards
endoderm examples
liver, pancreas, thymus
mesoderm examples
skeletal system, muscular system, notochord
ectoderm examples
cornea and lens of ete, nervous system, spidermis of skin
Triploblastic
has three germ layers: the ectoderm, endoderm, and mesoderm.
Diploblastic
having two germ layers; ectoderm and endoderm
endoderm develops into
gut lining
mesoderm
source of muscles
ectoderm
start of the tissue that linesthe body surface
2 animal body plans
cavities, layers in embryo
gastrula parts
ectoderm, mesoderm, endoderm, archendom, blastocoel,blastopore
animal embryotic development
- Zygote –> eight cell stage –>blastula –> gastrulation –> blastopore
posterar is towards the
tail
dorsal body part is towards
upper part or back of the standinganimal
ventral body part is towards
lower part of body, if standing its stomach area
anterior body part is towards
the head
body regions in bilateral animals
anterior, posterior, dorsal, ventral
bilateral symmetry
one plane of symmetry
radial symmetry
infinite planes of symmetry
arthropods
most diverse species of animals
invertabrate
make upover 95% of the known species ofanimals
the vertabrates include
mammals,birds, reptiles, amphibians, and fishes
animals have ___ in some stage of life
mobility
most animals perform what type of reproduction
sexual
animals are ____ heterotrophs
aerobic
animals are
multicellular, most have tissues, organs, andorgan systems
first animals
sponges
Choanoflagellates are similar to a part of a sponge called
collar cell, choanocytes
First animals appeared approx
800m years ago
Coelom
a fluid or air-filled space located between the
digestive tract and the outer body walldigestive tract and the outer body w
function of coelom
prevent injury to internal organs, enables
organs to grow and move independently of the outerorgans to grow and move independently of the outer
body wallbody wall
True coelom forms from the
mesoderm
animals with a
true coelom are known as
coelomate
what are psuedocoelomates
a coelum that is formed from both the mesoderm and
the endoderm
psuedocoelomates are ancestral to
coeluoms
acoelomates
lack a body cavity
acoelomates are ancestral to
psuedoceolmates
coelomate
all vertebrates;
some derived groups of
invertebrates (earthworms)
psuedocoelomate animal
Nematoda
acoelomate animal
Platyhelminthes: Planarians
(most ancestral condition)
why must acoelomate animals remain small?
they have no coelom so organs and skin touch and if grow there body will explode. they can grow vertically. they can only grow in length
Protostome
Development v.
Deuterostome
Development
- Cleavage
- Determination of
earliest cells - Coelom
Formation - Fate of the
Blastopore***
PDvDD cleavage
protostome spiral and determinat
deuterostome radial and indeterminant
PDvDD determination of earliest cells
protostome in earliest stages; those cells have already been designated for a specific function (determinant)
deuterostome cells have yet to be given a function (stem cells)
PDvDD fate of blastopore
protostome becomes mouth
deuterostome becomes anus
PDvDD coelom formation
protostome Mesoderms split and form coeloms
deuterostome folds of archentron form coelum
stem cell
not given a roll
determinent
cells assignment a role in early stage
spiral cleavage
cells divide in a circular motion
around the polar axis
radial cleavage
cells divide toward the
polar axis
All animals share a common ancestor
(ancestral colonial flagellate – protist)
the most ancestral animals
sponges
Eumetazoa
is a clade of animals with true tissues
eumetazoa includes all animals except
sponges
Most animals demonstrate
bilateral symmetry
Chordates and Echinoderms are
deuterostomes
deuterostome development is
derived
protosome development is
ancestral
Rapid mitotic division is known as
cleavage
means empty in biology
coel
cephalization
an evolutionary trend of the concentration of sense organs and nerve control towards the anterior end of a animal
archentron
hallow space
blastopore
entrance to archentron
Outer layer of cells is
ectoderm
Gastrula is comprised of
: outer layer cells(ectoderm), endoderm
inner layer of cells is
endoderm