1_Introduction Flashcards
Invertebrate classification and
relationships are based on?
Cell number/embryology
Symmetry
Lifestyle and Habitat
Evolutionary Relationships
What are the three major invertebrate classification and relationships?
CELL NUMBER
SYMMETRY
DEVELOPMENT
The two cleavage patterns are:
Radial cleavage and Spiral cleavage
In this pattern, early deuterostome embryo.
Four cells are undergoing
cleavages parallel with and
perpendicular to the original
body axis.
Radial cleavage
In this pattern, early protostome embryo.
Four cells are undergoing
cleavages oblique to the
original body axis
Spiral cleavage
What is the rearrangement of the cells of a blastula to form an embryo? and what is its 3 germinal layers?
Gastrulation;
Ectoderm, Endoderm & Mesoderm
What is a body cavity (fluid space) found within
coelom
Functions of coelom:
- Space for development of internal
organs - Allows gut to work separately from the
body wall - Fluid can act as a hydrostatic skeleton
- Fluid acts as a shock-absorber to
protect organs
a system of classifying (hierarchal
classification) and naming (binomial system of nomenclature) of organisms
Taxonomy
Who invented the taxonomy/ Hierarchal classification?
Carolus Linnaeus
Coelom formation:
Protostomes: ___________ - coelom formation occurs by the gradual enlargement of a split in the mesoderm.
Deuterostomes: _______________ - coelom of deuterostomes forms from a part of what eventually becomes the gut.
Schizocoely
Enterocoely
What are the three domain systems?
Bacteria, Archaea, & Eukarya
a taxon (group of
organisms) which forms a
clade, meaning that it
consists of an ancestral
species and all its
descendants.
Monophyletic Group
taxon is composed of
unrelated organisms
descended from more
than one ancestor.
Polyphyletic Group
– is a group of
organisms that
includes an ancestor
but not all of its
descendants.
Paraphyletic Group
Invertebrates form a
____________________
because their vertebrates
descendants (e.g.,
chordates) are excluded
Paraphyletic group
Types of Mobility?
Mobile
Sessile
Sedentary
Planktonic
FEEDING HABITS?
herbivores - eat plants/ algae
carnivores - eat animals
suspension feeders - filter small food particles
deposit feeders - consume organic matter from sediments
TROPHIC LEVELS
autotrophic - produce their own food
heterotrophic - obtain energy by consuming other organisms.
mixotrophic - can switch between autotrophy and heterotrophy
