Origin of Cells 1.5

Question 1

Endosymbiotic theory

Answer 1

is the leading evolutionary theory of the origin of eukaryotic cells from prokaryotic organisms

The endosymbiotic theory explains that some eukaryotic cell organelles, such as mitochondria and plastids, evolved from free-living prokaryotes

Evidence Includes:

Membranes — Mitochondria have their own cell membranes, just like a prokaryotic cell does
DNA — Each mitochondrion has its own circular DNA genome, like a bacteria’s genome, but much smaller
Reproduction — Mitochondria multiply by pinching in half — the same process used by bacteria

Question 2

Genetic Code

Answer 2

The nucleotide triplets of DNA and RNA molecules that carry genetic information in living cells.

Question 3

Louis Pasteur

Answer 3

He pioneered the study of molecular asymmetry; discovered that microorganisms cause fermentation and disease;

He set up two experiments. In both, Pasteur added nutrient broth to flasks, bent the necks of the flasks into S shapes, and then boiled the broth to kill any existing microbes.

Confirmed that spontaneous generation does not exist. Cells must come from other cells.

Question 4

Spontaneous Generation

Answer 4

The hypothetical process by which living organisms develop from nonliving matter

Common examples include: dust creates fleas, maggots arise from rotting meat, and bread or wheat left in a dark corner produces mice.

Question 5

Sterilization

Answer 5

Sterilization describes a process that destroys or eliminates all forms of microbial life and is carried out in health-care facilities by physical or chemical methods.

Question 6

Process Needed for Spontaneous Generation on Earth

Answer 6

Formation of simple organic molecules
Formation of polymers and complex organic molecules (aka polymerization)
Formation of self-replicating molecules
Formation of cell membranes
Water tends to break-down large molecules- need to protect molecules with membranes.

Question 7

Miller and Urey Experiment

Answer 7

Tried to reproduce the environment thought to have existed during the Hadean (pre-life Earth) in a closed system.

Question 8

Panspermia

Answer 8

The idea that life or complex polymers actually originated in space and travelled to earth by comets/meteorites.

Question 9

The first cells origin from non living material:

Answer 9

Miller and Urey Experiment: Compounds formed from re-creating environment from inclosed system

Question 10

Sterilization

Answer 10

technique used for the elimination of microbiological organisms to achieve a sterile microbial environment.