Lecture 1 - How did life on earth arise

Question 1

Vitalism

Answer 1

Religious theory, pre scientific

Question 2

Example/ argument for vitalism

Answer 2

Urea unique to living organisms and can be made form basic chemicals - when something unique to humans its seen as God

Question 3

Darwins theory

Answer 3

large body of water of chemicals randomly reacted to form life

Question 4

Oparin - haldene discovered whihc theory

Answer 4

Primodial soup theory

Question 5

Original Urey miller experiment + observations

Answer 5

set up flasks of water, hydrogen, ammonium + methane w/ spark - pretend lighteninig
after a day = colourless to pink
after a week = pink to red = amino acids present

Question 6

Orgel, crick, cech experiment - why it didnt work + improvement

Answer 6

try to prove DNA was starting point
DNA couldn’t of survived in the harsh conditions
Could of been RNA instead

Question 7

RNA theory - why ppl thought it wouldn’t work first + development

Answer 7

Though RNA had no enzymes but found Ribozyme which means RNA self replicating and can pass on its genetic info

Question 8

Why rna wouldnt work + development

Answer 8

difficult to make - base and nucleotide might not stick during early earth instead PNA = peptide nucleotide acid

Question 9

Characterisitcs of PNA

Answer 9

polyamide backbone instead of sugar

can pair w/ strands DNA, act as enzyme, transfers gentic info and can replicate

Question 10

How was PNA found

Answer 10

Urey miller repeated experiment with gases actually present on early earth and found PNA

Question 11

Compartmentalisation

Answer 11

scientists argued dont need genetic info or proteins but membrane important

Question 12

what did oparin find in primordial soup theory

Answer 12

coacervates= very basic cells - like oil sits on water (insouble) end up reacting + can take in chemicals or split off and grow

Question 13

Evidence for primordial soup

Answer 13

presemce montmorillonte (clay) + coacervates one earth earth and m catalyses reactin of C

Question 14

Hypothermal vent/ metabolism theory`

Answer 14

most evidence- lots organisms near vents + life present
v hot + acidic so life prestn but not for long
so forms and then moves to sea
alkaline vents discovered and acidic sea= proton gradient so energy

Question 15

LUCA

Answer 15

last common ancestor - evidence for vents

look at bacteria work back to common gene- can metabloise hydrogen and use proton gradients

Question 16

Phylogneetic tree

Answer 16

show how things related

Question 17

3 groups of life

Answer 17

Bacteria Archea Eurarya

Question 18

Eukaryote

Answer 18

orgnaism consisting of a cell or cells where fnentic infor in dna un form chromosomes cintained w/in nucleus

Question 19

Bacteria

Answer 19

member of a large group of unicellular organisms whihc have cell wall but lack organelles +unorganised nucleus - some can cause disease

Question 20

Archea

Answer 20

microorganism similar to bacteria in size and simplicity of structure but radically diff in molecular organisation

Question 21

difference between prokaryote and archea

Answer 21

both prokaryote
histone - no histones
both 70s ribosomes but diff shape
sensiitve to antibiotics - not sensitive

Question 22

examples extremeophile

Answer 22

human gut and most archea

Question 23

how to prokaryotes replicate

Answer 23

binary fission

Question 24

Prokaryotes characteristics

Answer 24

linear Dna
membrane bound organelle
no cell wall
cytoskeleton

Question 25

Why ribosomes support RNA theory

Answer 25

has own RNA

found in mitochondria + chlorplasts

Question 26

functions of er

Answer 26

SER lipid synthesis- molecule modification

RER protein sorting

Question 27

Golgi apparatus

Answer 27

flattened sacs- modification transport and dispatch proteins

Question 28

lysosomes peroxisomers vacuoles

Answer 28

breaks things down

Question 29

Peroxisomers

Answer 29

oxidative enzymes break down fatty acids

Question 30

Mitochondria

Answer 30

gnerate energy
double membrane
mitochonr=drial dna only from mum

Question 31

chloroplasts

Answer 31

3 membrance - thylakoid and chlorphyll

circular DNA

Question 32

endosymbiotic theory

Answer 32

how multicelluar from single
chlotoplast and mitochondira own DNA because ancestral prokaryote engulf either one end u with symbiotic relationship - didnt kill prokaryote and gained enrgy to form photosynthesising prokaryore + aerobic prokaryote

Question 33

Syncytial theory

Answer 33

multiple nuclei

aggregate cells + membrane formed around cells - inner meembrance differente differently so diff organs

Question 34

Colonial theory

Answer 34

most ec-vidence aggregatess of same species

basic cells aggregate togther but not divided as should and w/ in group they differentiate

Question 35

7 kingdoms

Answer 35

animals fungi bacteria chromista protista archea plantae