Animal Diversity Flashcards
How are animals classified and who devised the system?
Classified according to the Hierarchial System devised by Linnaeus.
What is the layout for the classification system?
Phylum Class Order Family Genus Species
What is the taxonomy for a human?
Phylum: Chordata Class: Mammalia Order: Primates Family: Hominidae Genus: Homo Species: sapiens
What is specific to the phylum, chordata?
Animals have a ‘backbone’
What are the four main characteristics for an animal?
Multicellular
Heterotrophic
Internal digestion
Movement and nervous systems.
How many phyla are within the animal kingdom?
Between 32-39
How many know species are there of the phyla, Cycliophora and where are they found?
Three known species which are found on the mouth parts of lobsters.
What is the estimated common ancestor between all animals?
A colonial flagellate
What phyla are sponges classified under and how many species are known?
Porifera and 5,500 known species.
Describe cells in a sponge
Cells are embedded in spongin and are supported by spicules.
How do sponges gain oxygen and food?
Provided from water currents that are generated by collar cells.
How do collar cells generate water currents?
Beating flagellum creates the water current.
What is a collar cell made up of and what are they alternatively known as?
Made up of micro hairs which filter tiny food particles. Sometimes know as choanocytes.
Name the cells sponges are made up of
Pinacocytes, porocytes and amoebocytes.
What is the role of pinacocyte cells?
They are contractile and so act a bit like muscle. They are able to slightly change the shape of the sponge and so can control water currents and also produce collagen.
What is the role of porocyte cells?
Allow water to pass through the body walls
What is the role of amoebocyte cells?
They move around the body and carry out a number of tasks.
Some secrete spicules or spongin and others become reproductive cells.
Why are spicules important?
Important for species identification and provide skeletal support.
What do species classed under the phyla Porifera all have in common?
All aquatic animals, mostly marine found up to 5.5 miles down.
How much water can a large sponge filter in a day?
1500 litres
Why is embryonic analysis important?
Provides key differences between animal groups.
Describe the embryonic development of a sponge
Zygote (cleavage) eight cell stage (cleavage) Blastula (gastrulation) Gastrula.
What are the two layers of cells called that make up a diploblastic embryo?
Endoderm and ectoderm.
What do the endoderm and ectoderm develop into?
Ectoderm develops into outer skin and endoderm develops into the gut lining.