ACT 11 - BIO 14

common attributes of animals

nucleus, membrane-bound organelles, multicellular, ingestive mode of nutrition, capable of sexual reproduction, capable of aerobic respiration, must be motile at some point

five grades of body organization

protoplasmic, cellular, cell-tissue, tissue-organ, organ-system

balance in the proportion in size and shape of animals

symmetry

types of symmetry

radial, bilateral, asymmetrical

division along a sagittal plane into mirror image, e.g., right and left halves

bilateral

tubular or vase form

radial

no symmetry

asymmetrical

symmetry in: Porifera

asymmetrical

symmetry in: Cnidaria

radial

symmetry in: Echinoderm

radial

symmetry in: Annelida

bilateral

symmetry in: Arthropoda

bilateral

symmetry in: Mollusca

bilateral

symmetry in: Chordate

bilateral

nervous tissues and sense organs are concentrated in a head, associated with bilaterally symmetrical animals

cephalization

body is organized into definite regions or segments

segmentation

segments are similar with each other

metamerism

segments are structurally different from one another and fused into functional groups

tagmatization

group of animals that lack dorsal bone support called vertebra or spinal column

Invertebrates

animals with backbone or spinal column or vertebra

vertebrates

two types of animals based on number of germ layers during embryonic development

diploblastic, triploblastic

produces 2 primary germ layers (endoderm, ectoderm), radially symmetrical, no body cavities, no organs

diploblastic

produces 3 primary germ layers (endoderm, mesoderm, ectoderm), bilaterally symmetrical, has body cavities, true organs

triploblastic

sequence of mitotic divisions that the zygote undergoes

cleavage

what do you call the smaller cells formed after the cleavage of a large cell

blastomeres

end of the cleavage where the zygote is divided into hundreds or thousands of blastomeres

blastula stage

increasing amount of yolk

isolecithal - mesolecithal - telolecithal

yolk evenly distributed throughout egg

isolecithal

yolk in the center of the egg

centrolecithal

large amount of yolk in one pole/tail of the egg

telolecithal

a yolk of intermediate size that is concentrated in one hemisphere

mesolecithal

two types of division patterns in cleavage

holoblastic (complete), meroblastic (incomplete)

types of isolecithal

radial, spiral, bilateral, rotational

which undergoes isolecithal - radial

echinoderms, amphioxus

which undergoes isolecithal - spiral

annelids, molluscs, flatworms

which undergoes isolecithal - bilateral

tunicates

which undergoes isolecithal - rotational

mammals, nematodes

which undergoes mesolecithal - radial

amphibians

which undergoes telolecithal - bilateral

cephalopod molluscs

which undergoes telolecithal - discoidal

fish, reptiles, birds

which undergoes centrolecithal

most insects

Cleavage subdivides the mass of the zygote until a cluster of cells called a ____ is formed

blastula

blastula cells form a layer around a central fluid-filled cavity called a?

blastocoel

To form a second germ layer, one side of the blastula bends inward in a process called

invagination

Converts the spherical blastula into a two- or three- layered embryo

gastrulation

The internal pouch is the gut cavity called

archenteron/gastrocoel

The opening to the gut, where the inward bending began is the?

blastopore

formed by endodermal cells moving into the space between the archenteron walls (endoderm) and outer body wall (ectoderm)

mesoderm

mesoderm lines outer edge of blastocoel, meaning body cavity is not entirely lined by mesoderm

pseudocoelomate

mesoderm completely fills body cavity

acoelomate

coelomic cavity forms inside mesoderm

eucoelomate

blastospore becomes mouth

protostome

blastospore becomes anus

deuterostome

examples of protostomes

molluscs, annelids, arthropods

examples of deuterostomes

echinoderms, chordates

fate of ectoderm

skin, nervous system

fate of mesoderm

muscles, skeleton, circulatory system

fate of endoderm

gut lining, internal organs

non-cellular gelatinous matrix found between the outer (ectoderm) and inner (endoderm) tissue layers of Radiata

mesoglea

body organization of porifera

cellular

how does porifera eat

filter feeders via canal systems, intracellular digestion

classes of porifera (based on spicules)

calcarea, hexactinellida, demospongin

structural support of porifera

calcareous skeletal spicules, flexible proteinaceous spongin

flagellated internal collar cells

choanocytes

Water enters sponges through microscopic incurrent openings called

ostia

excurrent opening that expels water

oscula

porifera with calcium-based spicules

calcarea

porifera with silicon-based spicules

hexactinellida

porifera with spongin, some with siliceous spicules, or both

demospongin

three canal systems in increasing complexity

ascon - sycon - leucon

radially symmetrical animals with no distinct internal organs but with definite tissue layers

cnidaria

a type of cell containing a large secretory organelle called a cnidocyst, that can deliver a sting to other organisms as a way to subdue prey, for food capture and defense

cnidocytes

sessile cnidaria body form

polyp

motile cnidaria body form

medusa

since cnidarians do not have a central nervous system, what does it have instead

nerve net

specialized cells in cnidarians that combine the functions of epithelial (covering) and muscular (contractile) cells.

epitheliomuscular cells

classes in cnidaria

hydrozoa, scyphozoa, anthozoa, cubozoa

Hydroids; most possess both medusa and polyp stages in their life cycle, with the polyp stage dominant. Most hydroids are marine and colonial.

hydrozoa

Jellyfishes; medusa stage dominant; polyp stage small, inconspicuous, and simple in structure. All solitary and marine.

scyphozoa

Corals, sea anemones and their relatives; only polyps occur in the members of the class, and they may be colonial or solitary.

anthozoa

box jellyfish

cubozoa