Exam 1

What experiment lead to the idea that organic molecules can be generated through electricity in the earth’s atmosphere?

Miller-Urey Experiment

When was the earth formed?

4.5 BYA

When did the earth become habitable for life?

3.8-3.9 BYA

When did first life evolve on earth according to the fossil record?

3.5 BYA

When did oxygenic photosynthesis first evolve?

3 BYA

When did eukaryotes first evolve?

2 BYA

When did eukaryotes acquire mitochondria through endosymbiosis?

1.6 BYA

When did eukaryotes acquire chloroplasts through endosymbiosis?

1.5 BYA

When was The Big Bang?

14 BYA

When was the end of heavy bombardment on earth?

4 BYA

What three things were important about the end of heavy bombardment?

The earth cooled, thousands of years of rain, earliest time life could exist

When was the primordial soup theory supposed to take place?

3.8 BYA

What three locations are involved in the primordial soup theory?

Tide pools, ocean, atmosphere

What was the 4 vessels setup for the Miller-Urey experiment to prove the primordial soup theory was plausible?

Water and heat, gas chamber for steam with electrodes, condenser, and water analysis

What was first found after the Miller-Urey experiment?

Amino acids

What changed in order to find nucleic acids and lipids and carbs in the Miller-Urey experiment?

Different atmosphere

For both the PST and DOT: Inorganic compounds to what?

Organic compounds

For both the PST and DOT: Organic compounds to what?

Polymers

For both the PST and DOT: Polymers to what?

Enzymatic molecules and self replication

For both the PST and DOT: Enzymatic proteins and self replication to what?

Enzymatic molecule networks

For both the PST and DOT: Enzymatic molecule networks to what?

Enzymatic molecule networks within lipid membranes

What was the two problems with the PST?

Temperature was too high and UVR was too high (no ozone layer)

Where does the Dark Origin Theory take place?

In the ocean within rifts created by tectonic plates

Within the black clouds expunged from these rifts created by the tectonic plates bringing magma close to the surface, what compounds are found?

Hydrogen sulfide, carbon dioxide, iron, infrared light, hydrogen and carbon monoxide

In the dark origins theory, instead of tide pools where did the organic material gather?

In porous chambers within the rocks of the rifts (they survived because of the heat capacity of water creating a temperature gradient)

What was the first organisms found in the fossil record?

Stromatolites

Why were stromatolites able to be discovered even though they existed 3.5 billion years ago?

They form rock on top of themselves as they grow

Did stromatolite have community?

Yes

What is one way to tell there is life on a planet?

Oxygen in the atmosphere

3 billion years ago, what helped life diversify?

Production of oxygen in the air

Do bacteria have organelles?

Yes, but they are small

What are the three non-cellular life examples?

Viruses, viroids, and prions

What shape is this?

Coccus

What shape is this?

Bacillus

What shape is this?

Vibrio

What shape is this?

Spirillum

What shape is this?

Pleomorphic

What shape is this?

Coccobacillus (mix of coccus and bacillus)

What shape is this?

Diplococci

What shape is this?

Chain

What shape is this?

Sheets

What shape is this?

Packets

What shape is this?

Clusters

What bacteria stick together as a swarm, kill and eat other bacteria, and when dried or starved clump together to form a fruiting body with spores as the fruit (showing specialization)

Myxobacteria

What cells are specialized in some filamentous cyanobacteria to form a nutrient factory for the other cells, producing nitrogen in nitrogen-scarce environments?

Heterocytes

What are some macromolecules within the phospholipid bilayer?

Proteins, glycolipids, glycoproteins, etc.

What are four purposes of the cell membrane?

Regulate movement in and out, generate energy, uptake nutrients, and interact with environment

How many membranes can prokaryotes have?

3

Can Ions and charged particles diffuse through the cell membrane?

No

Can large molecules diffuse through the cell membrane?

No

Can water diffuse through the cell membrane?

Yes

Can gases diffuse through the cell membrane?

Yes

Can urea diffuse through the cell membrane

Yes

Can small hydrophobic molecules diffuse through the cell membrane?

Yes

Can ethanol diffuse through the cell membrane?

Yes

What membrane?

Gram negative

What is the word for 2 and/or 3 membranes?

Gram negative

What bacteria have 3 membranes?

Cyanobacteria

When ions and water are not allowed to diffuse this is known as?

Disequilibrium

What membrane?

Gram positive

What is osmosis in this class?

Water moving across the membrane toward ions

Hypertonic, hypotonic, or isotonic?

Hypertonic

Hypertonic, hypotonic, or isotonic?

Hypotonic

Hypertonic, hypotonic, or isotonic?

Isotonic

What type of cell membrane transport requires no work and releases a proton gradient?

Passive transport

What type of cell membrane transport requires work and moves ions against the gradient?

Active transport

What type of cell membrane transport requires a protein to bring the molecule through the membrane?

Active transport

What is an example of passive transport?

Ion channels

What is an example of active transport

Proton motive force

What is an example of the active transport that gets proteins to bring molecules across the memebrane?

ATP binding cassette

What is an example of group transport across the plasma membrane?

Glycolysis attaching a phosphate to glucose to get it across the membrane

What is another example of active transport that requires atp?

Protein secretion

What is the cell wall made of?

Peptidoglycan

The alternating NAG and NAM “bricks” of the cell wall are made of what?

Sugars

The “glue” between the “bricks” of NAG and NAM are made of what?

Amino acids

The “glue” that is between the “bricks” of NAG and NAM attach where?

NAM

In gram positive cells, the “glue” between the “bricks” of NAG and NAM include what alteration?

A glycine linker

If you are staining cell walls, which will remain violet after washing?

Gram positive

What type of cell wall can be counter-stained for further identification?

Gram negative

What medicine affects cell walls and inhibits the enzyme that connects two NAMs?

Penicillin

Can penicillin affect current cells or does it only affect newly formed cells?

Newly formed cells

When does transpeptidation occur?

Cell division

What enzyme can break the bonds of NAG and NAM, that is also produced in our tears?

Lysozyme

What polysaccharide structure is very important for connecting biofilms?

Capsules/Extracellular polymeric structures (EPS)

Biofilms provide protection from what three hazards?

Viruses, antibacterial agents, and desiccation

Biofilms and, more specifically, EPS help attach to what two things?

Surfaces and other microbes

Why are biofilms so resilient?

Most antimicrobials can only penetrate the first layer which can be regrown

What are extreme versions of biofilms that exist in hot springs, lakes, and coastal intertidal zones?

Microbial Mats

What is the filament called that makes up the flagella?

Flagelin

How is a prokaryotic flagella powered?

Proton motive force to spin 360^o

What type of flagella?

Polar

What type of flagella?

Peritrichous

When bacteria want to move forward with their flagella, which way does it rotate?

Counter-clockwise

When bacteria want to tumble, which way does their flagella rotate?

Clockwise

Why can’t bacteria steer their flagella?

They are too small

Why can’t bacteria sense where something is coming from?

They are too small, one side of the bacteria feels what the other side is feeling

How do bacteria move toward a food source?

They can sense concentrations over time and judge if they are going toward or away from something

Bacteria who are attracted to chemicals are known as?

Chemotaxis

Bacteria who are attracted to light are known as?

Phototaxis

Bacteria who rely and magnets to orient themselves are known as?

Magnetotactic