Week 10 Flashcards
What kind of genetic material was in most organisms for a long time?
RNA
What different theories exist for how life came about?
hydrothermal vents, primordial soup (with amino acids), asteroids
What does photosynthesis convert sunlight into? how?
biomass through autrophy
How does photosynthesis work?
Sunlight, carbon dioxide, and water get turned into oxygen (byproduct) and glucose (carbohydrates)
what two colors are used for photosynthesis?
red and blue
What are C3 plants?
- have rubisco metabolism which requires lots of water because the leaf’s stomata co2 loss during respiration
- calvin-benson cycle
- they were the standard until 65 mya
- most trees and plants
- puts 3/4 carbons together for energy?
- positive feedback?
what are C4 plants?
- have PEPC metabolism which requires lots of sun
- water efficient, doesn’t lose it during photorespiration
- came into being when things dried up 65 mya (cenozoic)
- insulates calvin-benson cycle with o2?
- most grasses, sugar, corn
What is sex and why is it good?
- allows for the mixing of genes
- miosis instead of mitosis
- variable offspring
- adaptive evolution
what are eukaryotes and when did they develop?
- complex organelles
- RNA/DNA in nucleus, membranes
- 1.8 bya
Describe multicellular organisms that
- eukaryotic cells that specialized (into structural, metabolic, etc ones)
- made complex organisms possible
skeleton facts
- developed during the cambrian explosion 550 mya
- increased biodiversity in the water (calcium carbonate, shells)
- first developed as collogen
when did land plants develop? what kind were they?
- 500 mya late cambrian
- non-vascular plants like mosses and liverworts
when did insects appear?
early ordovician
wheb did land vertebrates appear? what kind?
- 425 mya silurian
- amphibians
- reproduced in bodies of water
- millipedes
describe the amniotic egg
- eggs have fluid that allows fetus to survive out of water
- shells protect fetus from harsh environment
- eggs can exchange O2 and CO2 in and out
what are the different kinds of potential energy?
- nuclear
- electrical
- gravitational
what does energy mean?
ability to do work
what are the laws of thermodynamics?
- energy moves between two bodies
- energy conserved
- moves from organized to chaos (energy lost)
- absolute zero cannot be reached
what are the two kinds of energy? what do they mean?
kinetic: motion
potential: stored energy
List the trophic levels. define them too.
- auto/chemotrophs: make their own energy (primary producers)
- herbivores: eat plants
- carnivores: eat other animals
- supercarnivores: exists in the ocean (mercury gets concentrated)
- decomposers: eat dead things
where can we see many trophic levels?
in the ocean- phyto and zoo are unique
do trophic levels only move one way?
no, some species feed at many levels
what is the community effect? give an example
- when feeding habits affect ecosystem function
- animals depend on each other
- otters, kelp, sea urchins, and reproductivity
what does productivity mean?
the amount of biomass/energy/carbon that can be incorporated into other organisms
how can we understand ecosystem function?
following the energy
what does gross primary productivity mean?
the rate of photosynthetic carbon uptake
AKA photosynthesis
What is net primary productivity?
GPP- nighttime respiration
where is npp highest? why?
at the equator because there is more water there
what is net ecosystem productivity?
caron that plants do not respire
AKA soil and litter activity
what does net ecosystem exchange mean?
carbon transfer between land and atmosphere (perhaps water too?)
what are the different levels of energy storage?
tissue -> leaves (we eat reproductive organs) -> fat
what do chemoautotrophs use to make energy?
sulfur compounds
what are heterotrophs? give examples
they make organic matter from other organics
ex: animals, fungi, bacteria
what do organisms use energy for?
work and growth
list the trophic levels
primary producers, primary consumers, secondary consumers, and tertiary consumers
how much energy is available to each trophic level?
there 90% less energy at each trophic level (90% of energy is lost)
ie. 1M -> 10k -> 1k -> 100 -> 10
what is the limiting agent on land? in oceans?
land- water
ocean- nutrients
how do we calculate ecologic efficiency?
energy provided by a trophic level / energy used
- comes out to be between 2-10%
what does succession mean?
how an ecosystem matures through evolution from one stage to another
what is primary succession?
- from scratch
- where there was nothing before
ie glaciation, pond filling
what is secondary succession?
- a restart after a disaster
ie fire, storm, saw
what do colonizers do?
provide soil and nutrients but they are short-lived plants with low needs
What is the order in which species move in for succession?
colonizers (herbaceous plants), early (pines), late (maples/oaks)
describe the conversion of a lake via succession
- sedge lays down floating runners creating a floating mat strong enough to support other plant while sediment is deposited at the bottom of the lake until it is filled in
how does community structure change through time during succession?
- biomass and diversity increase (peak) the go down and then squiggle from there
- soil organic matter and total ecosystem storage of chemical elements increases than decreases slowly until stabilizing in the middle
- a lot of nitrogen fixation before plummeting
- plant and litter stable at a low point
- small bump in soil phosphorus
what does facilitation mean?
- set the stage for others to come
- prepare the landscape
- stabilize environment
what does interference mean?
- when pioneer species prevent the growth of others
what does chronic patchiness mean?
- when species don’t mess with each other leaving gaps
- when the physical environment is too harsh for succession to occur
compare and contrast early vs late successional species
early: quick to germinate and grow
late: slow growing but live longer
