Lecture 4 Flashcards
What are the simplest life forms?
Viruses
What are viruses made up of?
Proteins, RNA and DNA
What is the function of RNA?
It codes, decodes, regulates and expresses genes
What’s the function of DNA?
It’s genetic material in all life for growth and development
What’s the importance of carbs?
Creating metabolism and energy resources, which are the building blocks of life
Why are viruses considered diseases?
Because they attack the building blocks of life
How old is our modern atmosphere and what elements does it contain?
It’s 3 billion years old and contains N2, O2, Ar, CO2 and H2O.
What are the key concepts of the Archean?
4.6-2.5 billion years old, has a thin, mobile crust, few plate-tectonic processes, minor weathering, unstable depositional environments, immature, detrital textures (sediment, sandstone) and minor carbonates
What are the key concepts of the Proterozoic?
2.5-570 million years old, thick stable crust, many plate-tectonics, significant weathering, stable depositional environments (sediment was deposited), mature detrital textures and common carbonates.
What are features of Prokaryotes?
Bacteria, cyanobacteria (e.coli), 1-10 micrometers, anaerobic-aerobic, non-motile with flagella, cell walls sugar, peptide, *no membrane-bounded organelles, DNA looped in cytoplasm, reproduce by binary fission, unicellular
What are features of Eukaryotes?
Protists, fungi, plants and animals, 10-100 micrometers, aerobic, motile, cellulose/chitin, mitochondria and chloroplast, DNA in nuclear membrane, reproduce by mitosis/meiosis and are multicellular
When were the earliest life forms originated?
3.8 billion years ago
When were humans originated?
10,000 year ago
What are the limitations of nutrient cycling?
There’s only 94 natural occurring elements, 6/17 account for 95% of all matter in life forms.
What are the 6 elements of life?
N, C, H, O, P and S
What are the parts of the ecological pyramid?
1st trophic level- producers (plants)
2nd trophic level- primary consumers (herbivores)
3rd trophic level- secondary consumers (carnivores)
What happens while trophic levels increase?
While trophic levels increase, the loss of energy available to use by successive trophic levels decreases by 10-20%
What happens when you go down trophic levels?
There’s an increase in biomass in the ecosystem.
What are the abiotic and biotic components of an ecosystem?
Abiotic: sun, solar radiation, heat energy loss
Biotic: producers, consumers and decomposers
Where did human species originate?
In Africa, 4.5 million years ago
When did humans begin to migrate away from Africa?
100, 000 yeas ago to Europe, 60,000 to Asia and 15,000-35,000 to North America
What is the series of events of climate vs. time?
There was an ice age and extinction of mammoths, then Egypt and early civilization occurred, Romans and now present day.
