1. Flashcards
Name the 5 phyla from least complex to most complex:
- Phylum Cnidaria
- Phylum Platyhelminthes
- Phylum Annelida
- Phylum Arthropoda
- Phylum Chordata
Name examples of Cnidaria.
Jellyfish and hydra
What type of symmetry do Cnidaria have?
Radial symmetry
Are Cnidaria diploblasts or triploblasts?
What do these terms mean?
Cnidaria are diploblasts
Diploblasts - organisms possess two layers, the endoderm and the ectoderm
Triploblasts - organisms possess three layers, endoderm, ectoderm and mesoderm.
(Endoderm = innermost layer, mesoderm = middle layer, ectoderm = outermost layer)
Do Cnidaria have an anus or coelom?
No, they don’t have an anus or coelom.
Coelom = body cavity filled with fluid where organs are suspended.
What type of skeleton do Cnidaria have?
Do Cnidaria have segmentation?
Hydroskeleton
No segmentation
Name examples of Platyhelminthes.
Flatworms, planarian & liver fluke.
Are Platyhelminthes multicellular or unicellular?
Multicellular
What kind of symmetry do Platyhelminthes show?
Bilateral symmetry
Platyhelminthes are flattened…
Dorso -ventrally
Are Platyhelminthes diploblasts or triploblasts?
Triploblasts
Do Platyhelminthes have an anus or a coelom?
No anus
Acoelomate = no coelom
What type of skeleton do Platyhelminthes have?
Hydroskeleton
Do Platyhelminthes have segmentation?
No segmentation
Describe Platyhelminthes organ systems.
Well-differentiated organ systems
Name examples of Annelids.
Earthworms and lugworms
Are annelids diploblasts or triploblasts?
Triploblasts
What symmetry do Annelids show?
Bilateral symmetry
Are annelids coelomate?
Yes (they have a coelom)
Annelids have a _____ - _____ gut
One-way gut (mouth and anus)
Annelids have segmentation. Describe this.
Each segment has its own muscle, blood vessel and nerve supplies. Some have reproductive organs.
What type of skeleton do Annelids have?
Hydroskeleton
Name examples of Arthropoda.
Insects and spiders
What type of skeleton do Arthropoda have?
Exoskeleton
Are Arthropoda diploblasts or triploblasts? What type of symmetry do they have?
Triploblasts
Bilateral symmetry
Describe the segmentation in Arthropoda.
- Fixed number of metameric segments
- Greater degree of specialisation than Annalids.
What is a notable fact about Arthropoda?
They are the most successful Phylum.
Arthropoda are haemocoel. What does this mean?
They have a reduced coelom.
Arthropoda have a brain. What is the term that describes the presence of a brain?
Cephalisation
What else do Arthropoda have apart from a brain?
Ventral nerve cord
Complete digestive system
Name examples of Chordata.
Mammals and birds.
What type of symmetry do Chordata show?
Bilateral symmetry
Describe the coelom of Chordata.
Well-developed
Describe the segmentation of Chordata?
Head, thorax and abdomen in humans.
Do Chordata show cephalisation?
Yes - they have a brain
Describe the nervous system of Chordata.
Complex
In Chordata, segmented muscles are in __ _______ _____
An unsegmented trunk
What type of circulatory system do Chordata have?
Closed circulatory system.
Are Chordata coelomate?
Yes
Chordata have a completed digestive system with the highest degree of specialisation. What else do they have?
Calcified bones
Jointed limbs
Highly differentiated tissues.
For Annelids, gas exchange occurs along…..
The length of its body.
Describe an insect.
3 pairs of jointed legs
2 pairs of wings
Head, thorax and abdomen
Describe a spider
Head and abdomen
4 pairs of jointed legs.
Define radial symmetry
Body parts radiate out from a central point.
Define bilateral symmetry
Right and left sides of the body are mirror images of each other.
