Animal Diversity Intro Flashcards
Describe the foundation of kingdoms
- created by Linnaeus
- split into 3 kingdoms: animals, plants, minerals
Describe the development of kingdoms
Hogg and Haeckel
- added protists and eukaryotic microorganisms
- removed minerals
Whittaker
- created 5 kingdoms: plants, fungi, animals, protists, bacteria
Woese
-created rRNA analysis
-added 3 domains: animalia, plantae, fungi
Explain rRNA analysis
In protein synthesis ribosomes are used for translation
DNA makes RNA to code for the ribosomes = rRNA
They are slightly different in all species - can be used to find similarities between species and see evolution
What are the different ways of classifying?
- morphology (looks)
- nucleus acids
- biogeography (habitat)
What is the hierarchical classification system?
Domain Kingdom Phylum Class Order Family Genus Species
What should you use if an organism doesn’t fit into the hierarchy?
Super - if larger than one level
Sub - if smaller than one level
Infra - for inside a level
What is the proper way to name an organism?
Use genus and species name
If typed: genus capitalised and in italics
If written: genus capitalised and underlined
What are key features of animals? (8)
- multicellular
- larger (than Protozoa)
- heterotrophic
- motile (part/all post embryonic)
- polarisation along anterior-posterior locomotive axis (have front/back in direction of travel)
- epithelial system
- Ach/cholinesterase system
- monophyletic clade (all related to each other)
What is the importance of epithelial cells?
Flexible
- are complex shapes so compartmentalise so have anatomical complexity (make organs/organ systems)
Waterproofing
-held together with proteins
-have fluid filled spaces for support and concentration (stops shrivelling)
-pass urine
-animals without bones need for structure
What is a clade?
An organism and all its descendants
Can be shown through circular graph
What are the 5 main animal phyla?
-Sponges (Porifera)
-Ctenophores
-Placozoans
-Cnidarians
(All above don’t have bilateral symmetry - most do)
-Bilaterians
Describe Sponges
- around 8,500 species of sponge
- one of most ancient orgs
- loosely organised
- no true organs
- no specialised cell layers
- spicules (hard body elements)
- choanocytes = specialised feeding cells
Describe Placozoans
- only around 2 species (but they are found often)
- no mouth or gut
- diploblastic (2 cell layers)
- contractile fibre cell in the middle (helps move)
- not well studied
Describe Ctenophores
- around 250 species
- radial symmetry
- diploblastic: ectoderm and endoderm
- mesoglea (extracellular matrix)
- has a complete gut
- nervous system developed independently of other animals (means evolved twice)
- 8 ctenes (cilia rows used for movement/ teeth-like - are bioluminescent)
- may have tentacles that are used to catch prey
Describe Cnidarians
- soured 12,500 species
- e.g. jellyfishes, Sean anemones, corals
- gastrovascular cavity (space for circulation, digestion, gas exchange)
- typically have sessile and motile life stages
- nematocysts (specialised cell with hollow barbed thread that turns out from cell w/ stimulation, often contains poison)
Describe Bilaterians
-triploblastic (exoderm, endoderm, mesoderm)
Two major groups of orgs:
Happens at embryonic stage and will already have polarity
- protosomes: mouth made first from Blastopore (fold in the embryo)
-deuterostome: anal opening made first from blastopore
- ectoderm: turns into epidermal layer of skin
- endoderm: forms lining of gut liver and lungs
- mesoderm: forms muscle, bone, kidneys, blood, gonads and connective tissue
Which phyla become protostomes?
- flat worms
- annelids
- mollusks
- nematodes
- arthropods
Which phyla become deuterostomes?
Chordata
Describe flatworms
- structurally diverse
- can be free living or parasitic (all mostly gut endoparasites)
- most of 30,000 species are tapeworms/flukes
- vertebrates
- lophotrochozoan (clade) can be identified by RNA: has ciliated feeding tube and free living larvae stage
- schistosoma spp: causes sleeping sickness (over 200 mil cases a year)
Describe annelids
- e.g. worms
- segmented bodies & separate ganglia for each segment
- thin permeable body (useful for gas exchange)
- lophotrochozoan
Descibe mollusks
- most diverse lophotrochozoan
- large foot
- main organs in a visceral mass covered by a mantle
- e.g. squid, slugs, octopi, snails, muscles, oysters
Describe Nematodes
- ecdysozoan (day 3 layered cuticle/membrane): useful for gas exchange
- mostly roundworms
- unsegmented (contract body to move)
- many are predators and parasites
- has 3 sexes
- caenorhabditis elegans = org that has useful genetic model and has taught a lot about human life (scientists know its every cell and its see through so easy to observe)
- Ascaris lumbricoides = 25% pop infected by them
Describe Arthropods
- ecydsozoans
- diverse and numerous (around 1.2 mil species)
- segmented
- exoskeleton (made of chitin = waterproofing)
- muscles on the inside
- jointed and specialised appendages
Describe Chordata
-includes lancelets, tunicates and vertebrates
common features evident at some stage of development include:
-dorsal hollow nerve cord
-tail that extends beyond anus
-dorsal supporting rod (notocord)
