Test 1 Flashcards
Know what gasses were present in the earth’s atmosphere before 2 bya. Know relative proportions (p 508)
Gasses that were present: nitrogen (N), carbon dioxide (CO2), methane (CH3), ammonia (NH3), hydrogen (H) , and hydrogen sulfide (H2S).
· Proportions: Low O2, High N and CO2
Know what autocatalytic RNA molecules are (p.509)
RNA that self replicated and could catalyze
Where was the first hereditary information found? (p. 509)
RNA, it can carry genetic info and also be autocatalytic
Why would the evolution of life switch to DNA to carry the genetic code? (p. 510)
Switched from RNA to DNA b/c DNA is more chemically stable and replicates with fewer errors
What allowed earth’s early chondrites to survive and also allowing the earth’s original amino acids. Know what the source was (p. 509)
The early atmosphere was dense, slowing down the chondrites which contained at least 80 different amino acids
Determining absolute dates by radiometric dating requires what things? (p. 512)
Accumulation of daughter isotopes; loss of parent isotopes
What role did cyanobacteria play in earth’s development? (p. 516)
Cyanobacteria contributed the most to developing the earth’s early atmosphere; made oxygen later it’s why the atmosphere is what it is
What event took place at the end of the snowball earth period? (p. 517 – 518)
The Cambrian Explosion – accelerated growth of life
How far back does the body fossil record go? (p.514, Fig 25.7)
3.5 BYA
What effects or causes does 2 continental landmasses have when they converge? (p. 520)
Global Climate Change
· Change of ocean currents and wind patterns
· Net loss of inter-tidal zones and habitats
· Extinction of many species
In regards to morphology, how would Linnaeus classify organisms differently than modern biologists would
Linnaeus would have classified the Hawaiian sliver swords as multiple species
What would you expect from an organism with a large number of hox genes?
Hox genes are responsible for the growth of body parts, where they grow, and how big. If you have more hox genes you will be more complex organism. Provides positioning information
Know what Homeotic genes are (p. 526)
Basic features of positional information hox genes are type of homeotic genes
Understand the roles that different anatomical features may have.
For example: feathers were used for warmth before they were used for flight. Or that a lung can be used as a swim bladder when fish evolve. Lung changed into swim bladder in fish. This is called EXAPTATION
What does exaptation mean?
When a body part is utilized for a new purpose than it was before
Know why plants, fungi, and prokaryotes are placed in different Taxa (p. 557)
Their cell walls are made of different stuff
Where is peptidoglycan most commonly found?
Gram + bacterial cell walls, gram + has more peptidoglycan and gram- less peptidoglycan
What is plasmolysis?
When the cell membrane pulls away from the cell wall due to loss of water
sugar will lyse the cell wall of bacteria.
What are the unique characteristics of endospores? (p. 560)
They can survive harsh climates for long periods of time. BUT endospores are NOT present in all bacteria. They are also immune to acidity.
Understand and know what structures/processes are involved in conjugation
Sex pili and stuff
