Week 1 - Animal Diversity Flashcards
How do animals stand upright + are not blobs if they have no cell walls?
Collagen
Collagen (composition)
PROTEIN INNOVATION. Foundation of bone, crystals of calcium and phosphate are deposited onto it. Other tissues can be draped onto collagen.
What binds muscle to bone?
Collagen
What 3 things allow animals to move?
Collagen, muscle tissue and nervous tissue
What is a blastula?
Hollow multicellular sphere. A stage of an animal embryo
What is Gastrulation?
The infolding of the blastula.
What would happen if gastrulation was to change?
The fundamental meaning of what it means to be an animal would change
What are hox genes?
Set of genes that dictate embryonic development
Which phyla does not have any Hox genes?
Porifera
How many genes make up a set of Hox genes?
Up to 13
How many sets of Hox genes do invertebrates have
1
How many copies of the Hox gene set do vertebrates have?
4
Why are vertebrate organ systems more complex (ie. more bells and whistles but same base) compared to invertebrates?
Vertebrates have more copies of the Hox gene sets
In what geo. era did the animals ancestor come from?
Ediacaran era (635 mya)
When was the Ediacaran era
635 mya
What are the closest relatives to animals/ common ancestor? Why?
Choanoflagellates. They greatly resemble the cells that make up sponges’ bodies (choanocytes)
Earliest molecular and chemical evidence of animals?
1 billion years ago
Earliest fossil evidence of animals?
500 mya. Soft bodied ediacaran
What is so special about the Cambrian period?
Animals with muscles, neurons, collagen, hox genes appeared
What is needed for endo/exo skeletons?
Collagen
When was the cambrian period
542 mya
What is the cambrian explosion?
Radiation during cambrian period. MOST IMPORTANT MOMENT IN HISTORY OF ANIMAL EVOLUTION (bc start of hox genes, collagen muscle, nervous)
When did plants emerge?
Ordovician period (488mya) of the Paleozoic era
What caused the Cretaceous extinction?
An asteroid
When was the Cretaceous period?
145 mya
What caused the domination of mammals?
The cretaceous extinction killed off dinos, leaving their niches empty. MASSIVE RADIATION to fill those niches
What caused the success of mammals (after their radiation)
The domination of angiosperms. Why?- food source (modern: agriculture)
When was the radiation of mammals and birds?
Paleocene epoch of the paleogene period of the cenozoic era
When did the dominance of angiosperms start?
Eocene epoch (56mya) of the paleogene period of the cenozoic era
What are the body plans that sort the animal phyla?
Type of symmetry, embryonic tissues, body cavity, embryonic development
What are the types of symmetry?
Radial, bilateral, none
What’s weird about the porifera phyla?
No true tissues, no hox genes
Which phyla are radially symmetrical
Ctenophora, Cnidaria
What is cephalization?
The clustering of neurons and sense organs (formation of head + brain)
What is the clustering of neurons and sense organs (formation of head + brain) called?
Cephalization
What are the three embryonic tissues?
Ectoderm (the outside of the gastrula), endoderm (the inside of the pouch) and mesoderm (between endo and ecto)
What does the ectoderm produce?
nervous tissue, sensory system and epidermis of skin
What does the endoderm produce?
epithelial cells lining digestive and respiratory systems
What does the mesoderm produce?
dermis of skin, skeletal and muscle systems, circulatory sys, etc
What is a diploblastic animal? Name two phylas that are diploblastic
Only has ecto and endoderm- no mesoderm. Ctenophora and Cnidaria
What is a triploblastic animal? Which phylas?
Have all three layers (endo, ecto, meso). All bilateral animals are triploblastic
What is a ceolom
Fluid- filled space/ body cavity
What are ceolomates. Example?
Mesoderm covers and seperates the ecto and endo layers, creating a gap between the layers of mesoderm. Organs are suspended. Ex: earthworms (annelida)
What are pseudocoelomates? Example?
Mesoderm only covers ectoderm. Organs can move independently of the rest of the body. Example: nematoda (round worm).
What are acoelomateas? Example?
No cavity. Cavity is filled with cells. Ex: flatworm (platyhelminthes)
What are the characteristics for protostomes?
- Spiral cleavage.
- Determinate.
- Mesoderm splits into two
- Mouth develops from blastopore (formed first)
What are the characteristics for Deuterostomes?
- Radial cleavage.
- Indeterminate.
- Mesoderm pinches from endoderm layer, stays one
- Anus develops from blastopore (formed first)
