Chapter 1- Biological Theories

Question 1

Cell theory

Answer 1

1. All lifeforms have one or more cells
2. The cell is the most simple unit of life
3. All cells come from other cells

Question 2

Modern Cell theory

Answer 2

1. All life is composed of one or more cells, where cells are basic structural, functional, organizational unit of life.
2. All cells come from other cells via cell division, genetic information passed from cell to cell.
3. Metabolism and energy flow occur within cells, all cells have same chemical composition.
   (does not apply to viruses, not living thitngs)

Question 3

Central dogma of genetics

Answer 3

Information flows from DNA to RNA to Proteins.
RNA comes from DNA. Protein come from RNA.

Information moves interchangeably through RNA and DNA
but not protein to protein
not protein to nucleic acid
One exception: for protein - protein =Prions

Question 4

Prions

Answer 4

misfolded proteins that send information to other proteins to misfold, destroying their function

Question 5

RNA world hypothesis

Answer 5

says that the Earth’s “primordial soup” had a lot of RNA nucleoside triphosphates, which made phosphodiester bonds with each other to create short strands of RNAs. As the strands grew longer and longer, they became more and more stable.
hypothesis says that RNAs continued to evolve until they could replicate, either on their own or with the help of other small molecules in “primordial soup”

• Two central facts support the RNA world hypothesis:
  
  1. RNA can store genetic information like DNA
  2. RNA can catalyze chemical reactions like proteins