Class Notes (838,888)
Canada (511,142)
Biology (Sci) (2,472)
BIOL 111 (283)
Multiple (19)

October 18.doc

9 Pages
Unlock Document

Biology (Sci)
BIOL 111

Bio 111 Alanna Houston October 18, 2007 SPONGES Asexual Reproduction: - Fragmentation: o Not self-induced o Waves, predators - Budding: o Clone of parent Sexual Reproduction: - Hermaphroditic o Sperm and eggs develop inside single cells o Broadcast sperm o Filter in different sperm o Eggs fertilized, develop in jelly layer (mesohyl) o Larvae released o Settle on suitable substrate o Develop in sessile adult Sponge Origins: - Evolved ~ 700 MYA - Ancestor – coanoflagellate (protists) cells are similar to choanocytes of modern sponges Limitations of Sponges: - Very successful group, but… - Unable to feed on larger prey than choanocytes o Digestion is intracellular - Unable to achieve high level organization or coordination between body parts o Cellular level of organization o No tissues etc. cannot respond to stimulus and do not have muscles to move When in time first displayed a gut: C (look at phylogeny) Evolutionary innovations: - Gut o Enables extracellular digestion - Tissues o Enable body organization ANIMALS Which is not a characteristic of animals: - D: a haploid multicellular life stage - Their multicellular life stage is diploid Characteristics of Animals: - Eukaryotic - Heterotrophic Bio 111 Alanna Houston - No cell walls - Motile at some life stage - Multicellular - Have tissues - Life cycle mostly diploid - Unique embryonic development Embryonic Development - Embryo: a young animal or plant contained within a protective structure (seed, egg or uterus) - Zygote: multicellular organism - 2 major processes during embryonic development o Cleavage: cell division – process forming many cells from one cell o Gastrulation: infolding – process forming embryonic tissue layers (2-3) from one layer of cells o o Zygote – cleavage  morula (solid ball)  blastula (hollow ball) – Gastrulation  early gastrula and blastopore (opening)  late gastrula forming a higher bigger blastopore o Bio 111 Alanna Houston - Gastrula: o Layers of embryonic cells = germ layers o Germ layers: ectoderm (epidermis, nervous system) – outer layer, endoderm (lining of digestive and respiratory systems) – inner layer - Animals with two germ layers are diploblastic (simpler animals) o 3rs layer is called mesoderm (inside) – most internal organs: muscles, skeletal system, heart, stomach - Animals with three germ layers are triploblastic (us) - Blastopore turns into mouth of anus - Archenteron is the digestive space (gut cavity – one opening) - A tract has an in and an out whereas a cavity only has one opening - - Triploblasts start after cnidarians CNIDARIANS Challenge One: Obtaining Energy - Heterotrophic - Sometimes sessile during life - Multicellular – how get nutrients to all cells? (Cells have to be small) Must be another way other than simple diffusion - Capture food with cnidocytes (stinging cells) Bio 111 Alanna Houston o o Fastest most powerful cellular process o Can penetrate carapace of crab shell - Predators - Corals, Anemones, Sea fans, - Coral Reefs are in clear places (not much nutrients – symbiosis with photoautotroph) Body Plan: - Sac of cells - - Gastrodermis (from endoderm – lines digestive cavity) - Gastrovascular cavity (blind gut – from archenterons) - Mouth (from blastopore) - Epidermis (from ectoderm) - Mesoglea – jelly non-living layer (forms hydrostatic skeleton) - Diploblastic Two Forms: - Polyp o Sessile o Sea anemone - Medusa o Motile o Jellyfish Bio 111 Alanna Houston - Cnidarian Diversity: - Scyphozoans o Medusa is dominant, polyp is reduced o Jellyfish o Cup animals o Large amount of mesoglea o All marine o Example: Cassiopeia  Upside down jelly  Symbiotic algae – use algae to supplement O2  Tolerates low O2 conditions - Anthozoans o Polyp is dominant, no medusa o Coral
More Less

Related notes for BIOL 111

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.