Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
Age of the Earth: |
4.5 BYA |
|
Oldest known fossils: |
3.465 BYA |
|
Oldest known eukaryotic fossils: |
1.75 BYA |
|
Oldest known multicellular eukaryotic fossils: |
580 MYA |
|
Oldest known animal fossils: |
565 MYA |
|
Oldest known plant fossils: |
425 MYA |
|
The banded iron formations appear in sedimentary rocks that were (mostly) formed between 2.2 and 2.8 billion years ago. What is the significance of the banded iron formations in understanding the history of life? |
Evidence of 1st appearance of oxygen |
|
Many biologists believe that the appearance of plant fossils in the Silurian Period are a marker for when the land surface became available for occupation. Why might the land surface have been hostile to life prior to the Silurian? |
Early atmosphere contained co2, lacked o2. O2 makes up the ozone layer which protects from uv |
|
The proposition that life evolved from inorganic molecules (through the following sequence of events: inorganic molecules → simple organic molecules → organic macromolecules → complex structures → cells) is generally referred to as: |
Evolution? |
|
What is the name of the hypothesis that RNA was the original genetic molecule, and that DNA replaced RNA in this function later? |
RNA world hypothesis |
|
Who were the first researchers that were able to demonstrate the formation of simple organic molecules from inorganic precursors (using energy discharges in a sealed reaction vessel)? |
Miller and Urey |
|
Briefly explain why viruses are not included in the three domains of living things: |
Lack cell structure Lack metabolism No growth/development Don't interact w/ environment |
|
Viral nucleic acids are surrounded by a protein layer called the: |
Capsid |
|
Compare and contrast a lytic viral reproductive cycle with a lysogenic viral reproductive cycle: |
Lytic:Found in virulent viruses a) attaches to plasma membrane b) nucleic acid enters cell c) host cell dna is destroyed Lysogenic: temperate viruses a) attaches to plasma membrane b) viral dna becomes active |
|
Name one group of viruses whose nucleic acid is a single-stranded molecule of RNA: |
Togavirus, retrovirus, rhinovirus |
|
An infectious misfolded protein that causes other proteins to misfold is called a(n): |
Prion |
|
Briefly describe the cytological features of a “typical” prokaryotic cell: |
Small Unicellular Ribosomes DNA Loop Cell wall |
|
Most Bacteria have a cell wall composed of: |
Peptidoglycan |
|
How do Gram-positive bacteria differ from Gram-negative bacteria? |
Gram positive: thick layers of peptidoglycan (stain purple) Gram negative: thin layers of peptidoglycan (stain red) |