Animal Diversity Intro

Question 1

Describe the foundation of kingdoms

Answer 1

• created by Linnaeus

- split into 3 kingdoms: animals, plants, minerals

Question 2

Describe the development of kingdoms

Answer 2

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

Question 3

Explain rRNA analysis

Answer 3

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

Question 4

What are the different ways of classifying?

Answer 4

• morphology (looks)
• nucleus acids
• biogeography (habitat)

Question 5

What is the hierarchical classification system?

Answer 5

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 6

What should you use if an organism doesn’t fit into the hierarchy?

Answer 6

Super - if larger than one level
Sub - if smaller than one level
Infra - for inside a level

Question 7

What is the proper way to name an organism?

Answer 7

Use genus and species name

If typed: genus capitalised and in italics
If written: genus capitalised and underlined

Question 8

What are key features of animals? (8)

Answer 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)

Question 9

What is the importance of epithelial cells?

Answer 9

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

Question 10

What is a clade?

Answer 10

An organism and all its descendants

Can be shown through circular graph

Question 11

What are the 5 main animal phyla?

Answer 11

-Sponges (Porifera)
-Ctenophores
-Placozoans
-Cnidarians
(All above don’t have bilateral symmetry - most do)
-Bilaterians

Question 12

Describe Sponges

Answer 12

• 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

Question 13

Describe Placozoans

Answer 13

• 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

Question 14

Describe Ctenophores

Answer 14

• 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

Question 15

Describe Cnidarians

Answer 15

• 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)

Question 16

Describe Bilaterians

Answer 16

-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

Question 17

Which phyla become protostomes?

Answer 17

• flat worms
• annelids
• mollusks
• nematodes
• arthropods

Question 18

Which phyla become deuterostomes?

Answer 18

Chordata

Question 19

Describe flatworms

Answer 19

• 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)

Question 20

Describe annelids

Answer 20

• e.g. worms
• segmented bodies & separate ganglia for each segment
• thin permeable body (useful for gas exchange)
• lophotrochozoan

Question 21

Descibe mollusks

Answer 21

• most diverse lophotrochozoan
• large foot
• main organs in a visceral mass covered by a mantle
• e.g. squid, slugs, octopi, snails, muscles, oysters

Question 22

Describe Nematodes

Answer 22

• 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

Question 23

Describe Arthropods

Answer 23

• ecydsozoans
• diverse and numerous (around 1.2 mil species)
• segmented
• exoskeleton (made of chitin = waterproofing)
• muscles on the inside
• jointed and specialised appendages

Question 24

Describe Chordata

Answer 24

-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)