Class Notes (783,538)
Canada (480,727)
Biology (2,219)
BIO130H1 (431)
Lecture 2

Lecture 2 notes.docx

3 Pages
Unlock Document

University of Toronto St. George
Melody Neumann

Lecture 2 – January 9, 2014 - Tree of life: classification based on similarity in rRNA; came from a common ancestor cell o Broken into 3 domains  Bacteria  Archaea: in extreme environments  Eukaryotes: more similar to archaea - Clicker question#1: If we assume the diversity that we’ve just been talking about is the result of different genes or different patterns of gene expression are: o Modification of existing sequences o Synthesis of novel stretches of DNA - Two main types of cells o Prokaryotic  No nuclei; single celled  Plasma membrane, nucleoid, cell wall, ribosomes  Depend on diffusion  A lot simpler than eukaryotes  Eubacteria, archaea o Eukaryotic  Nuclei; single celled or multi-cellular  A 1000 times the volume of a prokaryote  Microtubules: give structure (part of cytoskeleton); Nucleolus: where ribosomes are made; Vacuole: regulates pressure in plant cells (turgor); Mitochondria; Chloroplasts  Have endo-membranes (ER, golgi body)  Plants, fungi, animals, humans - Eukaryotes evolved from prokaryotes. o Endo-symbiont theory: predatory nature of ancestral cell  Anaerobic ancestor  engulfed a bacterium which managed to escape digestion & provide ATP  Evidence • Genomes: mitochondria & chloroplast have their own genome • House-keeping machinery: have their own DNA machinery & protein synthesis • Double membrane (both with different composition): the prokaryote already had a membrane & when it was engulfed another membrane was put around it • Carnivorous single-celled eukaryote exits now - Clicker question#2: All of the following support the endo-symbiont theory except o Mitochondria & chloroplast only need RNA to replicate them selves - Approachestho study dithrsity o 19 & early 20 century: small info from looking at a few organisms o 20 & 21 century: using many mechanisms study model organisms - General attributes of model organisms o Rapid development with short life cycles o Small adult (reproductive) size o Readily available (collections or wide-spread) o Tractability – ease of manipulation or modification o Understandable genetics - Model system examples o Prokaryote  E. coli: heterotrophic eubacterium found in
More Less

Related notes for BIO130H1

Log In


Don't have an account?

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.