Animalia diversity and phylums Flashcards
What domain does kingdom animalia fall into?
Eukarya
What are some characteristics of kingdom animalia?
- Eukaryotic
- Multicellular
- Heterotrophic
- Huge diversity in morphology (structure, form)
What are the 3 types of symmetry?
- No symmetry
- Radial symmetry
- Bilateral symmetry
Radial symmetry
- Has a top and a bottom
- No front and back
- No left and right
ex. Sea anemones (Phylum: cnidaria)
Bilateral symmetry
- Top (dorsal) and bottom (ventral)
- Front (anterior) and back (posterior)
- Left and right sides
*Left and right is always the animal’s left and right
Cephalization
Evolutionary trend present in bilaterally symmetrical animals that has a concentration of sensory equipment (nervous tissue –> brain) at anterior end of body (head)
What kind of animals have radial symmetry?
- Sessile: Live attached to substrate
- Planktonic: Drift, weakly swim
What are the advantages of having radial symmetry?
Can meet environment equally well from all sides
What are the advantages of having bilateral symmetry?
- Move more and with direction
- They have the ability to choose and see where they are going correctly
True tissues
Collections of specialized cells isolated from other tissues by membranous layers
What animals do not have true tissues?
Sponges
How are tissues formed?
- Embryos become layered due to gastrulation
- Concentric layers of tissue (germ layers) form various tissues and organs
Ectoderm
- Germ layer covering surface of embryo
- Outer covering of animal
- Sometimes the central nervous system
Endoderm
- Innermost germ layer
- Lines archenteron
- Produces lining of digestive tract/cavity (liver and lings in vertebrates)
What are the 2types of tissue composition?
- Diploblastic
- Triploblastic
Diploblastic
Give an example
- Animals with only ectoderm and endoderm
ex. jelly fish, corals (phylum cnidaria)
Triploblastic
Give an example
- Animals with 3 germ layers
- Have mesoderm between ectoderm and endoderm
- All bilaterally symmetrical animals are triploblastic
ex. Crayfish, humans
Mesoderm
Forms muscle and organs between digestive tract and outer covering
Body cavity
- Most triploblastic animals have a body cavity
- Fluid or air filled space between the digestive tract and outer body wall
aka Coelom
Coelom
Main body cavity used to surround and contain digestive tract
Coelomates
- Have true coelom completely lined in mesoderm
Pseudocoelomates
Body cavity formed from mesoderm AND endoderm
Acoelomates
Have no body cavity
Functions of body cavities
- Fluid cushions suspended organs
- Fluid may act as a skeleton
- Internal organs can grow and act independently
Why are body cavities important?
The space created keeps organs from bumping into each other
Protosomes
- Display spiral, determinate cleavage
- As archenteron forms, solid masses of cells split to form body cavity (coelom formation)
- Solid balls of cell that can be acoelom, coelom, or pseudocoelom
- Blastopore form the mouth
Deuterosomes
- Display radial, indeterminate cleavage
- Mesoderm buds from wall of archenteron and cavity becomes coelom (coelom formation)
- Blastopore forms the anus
Characteristics of phylum porifera
Sponges
- Asymmetrical or radially symmetrical
- No true tissues
- Size can vary from a few mm to several m
- Mostly marine –> very few in freshwater
- Sedentary
How do sponges eat?
Suspension feeders
- Capture food particles suspended in water that passes through their body
- Water passes through pores and enters spongocoel
- Water flows out of osculum
- They capture food from the water passing through them
What are the different types of cells in porifera?
- Choanocytes
- Amoebocytes
Spongocoel
Large, central cavity of sponges where water enters through tiny pores and exit through osculums (openings)
Choanocytes
Line spongocoel in sponges
Amoebocytes
For intra-cellular digestion
- Use pseudopodia
- Take up food, digest it, carry nutrients to other cells
- Produce material for spicules
Hermaphrotic
Organisms that have complete or partial reproductive organs and produce both male and female gametes
Characteristics of cnidarians
Give an example
- Radial symmetry
- Diploblastic
ex. Hydras, jellyfish, corals
What is a cnidarian’s body plan?
- Sac with gastrovascular cavity
- Simple nervous system
How is a cnidarian’s gastrovascular cavity?
- One opening to cavity that acts as mouth and anus
- Incomplete digestion
- Enzymes secreted into gastrovascular cavity
- Cells lining the cavity absorb the nutrients
- Remains are expelled
Incomplete digestion
When the food comes in and goes out of the same hole. The gastrocavity takes up most space and most cells are close enough to take the nutrients so no need for separate tubes to transport nutrients around the body
How do polyps eat
Give an example
- Adhere to substrate with aboral end
- Extend tentacles and wait for prey
ex. Hydras, sea anemony
How do medusa eat?
- Flat, mouth-down version of polyp
- Moves passively or contracts body to move
Tentacles dangle from oral surface
Which animal has both polyp and medusa in their life cycle?
Obelia
Functions of tentacles
- Capture prey
- Direct food toward opening of gastrovascular cavity