Class notes
Biol184 Animals Notes
- Course
- Biology 184 (BIOL184)
- Institution
- University Of Victoria (UVic )
Biol184 Animals Notes
[Show more]
Seller
Follow
Content preview
Bio 184 Animals NotesCambrian Explosion
505 mya
Lots of new species – mostly bilaterians
Fossil evidence in Burgess Shale, BC
65 million years later – mass extinction of earlier life due to natural selection
1. Rise in atmospheric oxygen
Would help some species and hurt some
2. Homeotic genes evolved
Homeotic gene – regulate body plan
3. New predator prey relationships
New adaptations to attack or defend
Avg life span of species = 1 million years
Humans been around 100,000-200,000 years
99% of all life extinct
Animal features
1) Multicellular
2) No cell walls
3) Collagen – structural support
4) Nutrition – ingest all food
Different from plants (ps) and fungi (absorption)
5) Homeotic genes – regulate development and position of body parts
6) Diploid dominant lifecycle
Zygote – cleavage (mitosis) to 8 cells then to form blastula
Blastula – hollow ball of cells (cavity called blastocoel)
Gastrulation – one end of embryo folds inwards, expands and fills blastocoel
Archenteron – pouch formed from gastrulation
Pouch opens to outside via blastopore
Endoderm – walls of archenteron
Ectoderm – outside layer
7) Body plan
1. Symmetry
Radial Bilateral
Sides Oral, aboral Dorsal, ventral, anterior,
posterior, left, right
Blastic Diploblastic(no mesoderm) Triploblastic
Movement Sessile or drifting Move actively
Cephalization No Yes
e.g. Cniderians and comb jellies Everyone else
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller paytonbraun. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for CA$10.86. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
75632 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now