Animal DiversityLAB - Week 1

Sagittal Plane

bisects body into right and left halves

Frontal Plane

divides dorsal and ventral sides

Transverse Plane

divides anterior and posterior

Anterior

front or head end

Posterior

tail or hind end

Dorsal

back or uppermost side

Ventral

belly side

Lateral

side of the body

Medial

at or near midline of body

Cephalic/Cranial

head end

Caudal

trail end

Proximal

toward point of attachment

Distal

away from point of attachment

Longitudinal

lengthwise

Peripheral

parts away from the center

Superficial

on or near surface

Oral

mouth or region around mouth

Aboral

away from mouth

Radial Symmetry

any plane passing through longitudinal axis will divide body into like halves

Bilateral Symmetry

only a sagittal plane will divide the body into like halves

Characteristics common to ALL animals

-eukaryotic

-multicellular

-heterotrophic

-lack cell walls

-motile at some point

-sexual reproduction

Characteristics common ONLY to animals

-nervous tissue

-connective tissue

-develop blastula

Zygote → Morula → Blastula → Gastrula

fertilized egg, solid mass, hollow mass, opening forms

Diploblastic

2 germ layers

Triploblastic

3 germ layers

Blastocoel

center of blastula

Blastopore

forms either mouth or anus

Archenteron

hollow tube created by invaginated cells of gastrula

Protostome Characteristics

spiral cleavage, mosaic development, mouth first

Deuterostome Characteristics

radial cleavage, regulative development, anus first

Cladistics

biological system in which things are grouped together based on shared, derived characteristics

Molecular Phylogenetics

any method inferring evolutionary relationships from similarities or differences in molecular structure

Nested Clades

emphasize specificity and differentiation; what fits into what

Phylogenetic Tree

evolutionary history of an organism, relating to all extinct and extant species

Sister Group

two groups that are more closely related to each other than any other group

Outgroup

taxon that is closely related to, but not included within the focal group being studied

Homologous Traits (Shared Derived)

features among different organisms that share a common ancestor

Analogous Traits (Convergent Evolution)

features or structures in different species whose similarities are not due to common evolutionary origin

Monophyletic

Paraphyletic

Polyphyletic

Ectoderm

forms nervous system, epidermis, and nasal/oral epithelium

Endoderm

forms GI tract epithelium, digestive organs, and respiratory system

Mesoderm

forms muscle/bone/connective tissue and circulatory system