Lecture 4 Flashcards
6 key attributes of life
Order, Reproduction, Growth and development, Energy utilization, Response to the environment, and Evolutionary adaption
What is life (Biology)?
uses the combination of certain characteristics as signs of life, like metabolism, growth, reaction to stimulus, reproduction, etc. (every single one is not enough e.g. fire grows & breaths oxygen, crystals reproduce…)
What is life (Darwinian Evolution)?
is another main feature of life (even valid for viruses)
What is life (Physics)?
Physics uses entropy (level of discorder) as parameter, life is “negative entropy” (Schroedinger) i.e. it is reducing its own entropy at the expense of external sources
Key chemical ingredients of earth?
Life is a self-sustained set of chemical reactions based on + carbon (C) as the key chemical element and + water (H2O) as the key solvent
Most common elements in the universe?
H, C, N, O are the most common elements in just about every object in the
universe.
Why are abundances of elements so universal?
Hydrogen: has been around from the beginning
Carbon, oxygen: produced in red giant stars, which later explode as supernovae
Metabolism
needs sources of carbon and energy. All cells use adenosine triphosphate (ATP) as the basic energy currency inside the cell.
All life on Earth…
Uses ATP and is DNA-based -> we all share a common ancestor
DNA macromolecule:
genetic information
DNA’s structure is a double-stranded helix, and it resembles the look of a twisted ladder. The sugar and phosphates are nucleotide strands that form the long sides. The nitrogen bases are the rungs.
What does T pair with?
A
What does G pair with?
C
DNA replication process?
- DNA double helix
- Strands separate
- Each strand serves as a template for a new complementary strand
- Two identical “daughter” DNA molecules
What is a gene?
Basic unit of heredity in a living organism; genes hold the information to build and maintain cells and pass genetic traits to offspring.
What domain is animals and plants?
Eukarya
What is prebiotic chemistry?
Organic chemistry and aqueous solution, under plausible conditions of the primitive terrestrial environment, leading to compounds of biological interest
What was the science goal of the Miller-Urey experiment?
to simulate the formation of monomers, like amino acids
Natural selection is the name given to
The mechanism by which advantageous traits are preferentially passed on from parents to offspring
How does Darwinian evolution work?
By completely random selection of mutations that turn out to be advantageous for the survival of an organism
What is the evidence that supports the theory that all (current) life on Earth has a common ancestor?
All life uses DNA to encode the genetic information and uses the molecule ATP to store and release energy
