Evolutionary aspects of the animal kindom Flashcards
what is the biological definition of an aminal
refers to all members of the kingdom Animalia aka metazoa
what is the latin meaning if animal
form the latin animalis (having breath or having soul
how many know animal species are on the earth
there is more then 1 million know on earth
what kind of diversity do all animals on the planet have, how can they range
-diverse species
-diverse habitats
-diverse characteristics
what is monophyletic
meaning all taxa evolve form a single common ancestor
what is monophyletic
the animal kindom
what is phyla
group of animals or in some classifications plants sharing one or more major characteristics that set them apart from all other animals or plants and forming one of the main categories in biological classification that ranks above the class and below the kingdom
how can phyla be grouped
in clades
what are clades
a why that phyla can be grouped
what are some ways to define an animal
-multicelled eukaryote that lacks a cell wall
-heterotroph
-motile at least one point in their lives
-reproduce asexually or sexually (most)
-have nerves and muscles
when, how, and what from did multicellular eukaryotes most likely evolve
-form a colonial unicellular ancestor during the precanbrian era (700 mya)
-probably a flagellated protist
-cells in protists gradually became more specialized and layered
animals were probably a colonial flagellated protist what was believed to evolve from this
Choanoflagellates
a group of unicellular flagellated protists found in aquatic environments—and a sister group, the multicellular animals
how are the Choanoflagellates made up
they have a crown type head with a flagella sticking out. they made colonies with there “heads” pointing in that move together (some form of communication)
what evidence did conanoflagellates support
morphological and molecular evidance
what are the differences in a plant cell vs a animal cell
-plant cell has a chloroplast and cell wall, animals do not
-animal cells have centrioles, plants do not
if animal cells dont have a cell wall hoe is tissue stability achieved
through extracellular matrix and cell junctions. they are what allows cells to stay together and stay rigid
what are the different cell junctions
anchoring junction- have room between cells for things to pass through
tight junction- small space between cells allows for more control of what passes through
gap junction- important for synaptic transmission (nervous system)
animals can be based in features of there “body plan” what are these plans influenced by
-embryonic development pattern
-germ cell layers
-body symmetry
-body cavity type
what kind of reproduction do germ line cells undergo
meiosis to produce haploid gametes. but can also undergo asexual reproduction as well
what kinds of asexual reproduction can animals undergo
budding in hydra, fragmentation in echinoderms (starfish), and parthenogenesis in insects and come reptiles (development of unfertilized eggs)
what happens to gametes during fertilization in sexual reporduction
gametes fuse during fertilization to form a diploid zygote
what is zygote cleavage
-the division of cells in early embryos
-zygotes undergo rapid cell cycles with no significant growth
what does the zygote develop into after zygote cleavage
a compact mass of cells called morula
what does the morula turn into
it derives into a hollow sphere of single layers of cells termed blastula. this process in blastulation
why are zygote cleavage patterns important
it is an important trait that distinguishes two major lineages
what are protostomes
a zygote cleavage pattern that exhibits spiral cleavage- newly produced cells lie in the space between the cells immediately below them
what are deuterostomes
zygote cleavage pattern that exhibits radical cleavage- newly produced cells lie directly above and below other cells of the embryo
what cells are the development fates decided right away? which ones are humans?
-protostomes have a predetermined cell fate
-humans are deuterostomes meaning developmental fates of the first few cells are not determined
in deuterostomes what happens if a cell is removed form a morula
it will go on to form a complete organism (identical twins)
is the blastula see in everything
no it is specific to animals
what further happens after blastula
blastula invaginates and undergoes further differentiation into 2 or 3 (most amimals) germ layers
what are the three germ layers that form from blastula invaginating
ectoderm
mesoderm
endoderm
what do different germ layers differentiate to form
tissues and organs
what are diploblastic animals
i.e jellies, corals
they have two germ layers, the ectoderm and the endoderm
what are triploblastic animals
i.e flat worms, chordates (us)
have three germ layers ectoderm, endoderm, and mesoderm
what things does the ectoderm make up
skin and nervous system
what things does the endoderm make up
digestive tract
what things does the mesoderm make up
muscle and skeleton
what is the different orders of embryonic developments of the anus and mouth of protostomes and deuterostomes
deuterostomes- blastopore develops into anus; mouth forms later
protosomes- blastopore develops into mouth; anus forms later
what is the body cavity called
coelom
where does the mesoderm differentiate, and the coelom originate in protostomes
the mesoderm differentiates near the blastopore and the coelom (body cavity) originates as a split in the mesoderm (schizocoelom)
what is schizocoelom
the coelom (body cavity) originates as a split in the mesoderm
where does the mesoderm differentiate, and the coelom originate in deuterosomes
mesoderm originates form out pocketing of archenteron (primitive gut). the coelom develops from space within the outpocketings (enterocoelom)
what is the enterocoelom
coelom develops from space within the outpocketings
what is radical symmetry
can be divided equally by any longitudinal plane passing through central axis (diploblastic)
what is bilateral symmetry
can be divided along a vertical plane at the middle to create two identical halves (triploblastic)
what characteristics do animals with radial symmetry have
-diploblastic (except adult echinoderms)
-exhibits no left or right sides (have a top (dorsal and a bottom (ventral) side)
-often circular or tubular in shape with a mouth at one end
what do cnidarians and ctenophores have
often circular or tubular in shape with a mouth at one end
what are some features animals with bilateral symmetry have
-triploblastic
-balanced duplicate distribution of most body parts
-specialized head with feeding and sensory organs (cephalization)
-digestive chamber with two openings, mouth and anus
what is cephalization
specialized head with feeding and sensory organs found in animals with bilateral symmetry
what is segmentation
-seen in animals with bilateral symmetry
-repeated structures along the anterior-posterior axis
-seem in annelids, arthropods, chordates
-advantages: movement, specialization
what does the coelom do
it separates the gut form the body wall
what is a eucolomate
-most animals are
-a fluid filled cavity between the intestines and the body wall
-formed within the misoderm of the embryo
what is acelomate
-no body cavity
-flat worms (phylum playthelminthes)
-diploblastic are all acoelomates
what is psuedocoelomate
-fluid filled or organ-filled space between endoderm and mesoderm
-roundworms (phylum nematoda)
what are the phylum playthelminthes
Acelomates
what are the phylum nematoda
pseudocoelomate
why do we study animal diversity and evolution
-animals (and their body systems) have a common evolutionary history
-helps us to learn common principals
-animals occupy very diverse types of environments
-helps us understand environmental adaptaions
what is the physiological phenotype a product of
the genotype and the environment
what challenges must animals overcome to be able to survive and reporduce
-extract nutrients and O2/energy form the environment
-eliminate toxic metabolic waste form the body
-sense environmental changes and respond favourably
-maintain near constant internal body conditions
