Bio 1500 Final Exam UPDATED Exam
Questions and CORRECT Answers
Dragonflies - CORRECT ANSWER - Formidable aerial and aquatic predators
Identify dragonflies as ancient insects (when, what, why) - CORRECT ANSWER -
Carboniferous period (360 - 300 mya)
Identify huge body size as the outstanding characteristic of animals (including dragonflies)
during the carboniferous period - CORRECT ANSWER - ...
Dates of major milestones in the history of life on earth, as indicated in the online learning
module - CORRECT ANSWER - Earth formed - 4.6 bya
Oldest rocks - 3.8 bya
Oldest fossils (= signs of life) - 3.5 bya
Cyanobacteria - 2500 mya
Algea - 1200 mya
Cambrian Explosion - 545 mya
First dinosaurs - 230 mya
First birds - 150 mya
Dinosaur extinction - 65 mya
Modern humans - 200,000 ya
Identify interesting and 'unusual' events in the history of earth - CORRECT ANSWER -
"Snowball" - ice ages: the whole earth froze and created a giant ice ball, which was caused by the
Pangea, meaning instead of there being seven continents, there was only one supercontinent.
Cambrian explosion: The animals alive during this period are what interested me the most, they
almost look like crustaceans, but they are a million times bigger, which astonished me. One of
the animals described had five eyes!
,Recall environmental characteristics of the Carboniferous period - CORRECT ANSWER -
At the beginning of the carboniferous period, it is assumable that once again we have a giant
continent with only small break offs, and just complete water at the two poles. The continent
begins to expand to the poles, but one side of the earth still has no land and strictly just water.
Oxygen during this tie was at a pearl or beginning to peak ,eating that this was a time where
oxygen on the earth was higher than the eras before.
Relate changes of O2 levels in the atmosphere to biological events in the history of life -
CORRECT ANSWER - Oxygen concentration is a key physiological control on body size,
especially in groups like flying insects that have high metabolic oxygen demands. So, the more
oxygen in the air, the more consumption of oxygen by the dragonflies, increasing their organs,
and overall their size.
Recognize that all O2 on earth stems from biological processes - CORRECT ANSWER -
O2 was created by cyanobacteria, which are green bacteria that harvest energy from the sun and
create sugars, while O2 was the byproduct. (Photosynthesis)
Recognize the geology of earth has been dramatically changed by biology - CORRECT
ANSWER - 60% of earth's minerals are biogenic, which means the earth's minerals use
oxygen produced by life; they were generated through life.
Describe the mechanism of diffusion at the level of single particles - CORRECT
ANSWER - From high concentration to low concentration
Describe the pattern observed due to diffusion at the level of many particles - CORRECT
ANSWER - ...
Explain how the behavior of single particles explains the observed pattern at the many particles
level - CORRECT ANSWER - Each particle moves on its own, going from a naturally
high concentration to a low one, but this occurs by random particle movements. The particles
naturally go to a lower concentration, but this happens only by the particles colliding with other
moving particles. This then leads us to be able to predict, generally, where the molecules are
going, because as we stated, we cannot predict the exact movement of each individual particle.
, Diffusion - CORRECT ANSWER - • Movement of molecules from an area of high
concentration to an area of low concentration
• Driven by Brownian (thermal) movements of molecules
Particles move randomly on both sides
• There are more particles at the side of high concentration
• Thus, it is more likely one will move from high to low concentration
• This continues until there is an even number on both sides
• Random motion of individual particles result in the net flow of particles from high to low
concentration
Each molecule: - CORRECT ANSWER - Moves randomly (not directed to low
concentration)
Unpredictable
Never stops
Net (= total) movement of all molecules: - CORRECT ANSWER - From high to low
concentration
Predictable
Stops when reaches equilibrium
Diffusion over distance - CORRECT ANSWER - T = x2/ 2D T = time X = distance D =
diffusion coefficient (depends on temp)
• e.g. O2 in water: 10 micro(m) in 12 ms
1 mm in 2 mins
1 cm in 3 hours
1 m in 4 years
Diffusion is very efficient within most cells (1 - 100 micro(m) but is not useful over greater
distances)
Questions and CORRECT Answers
Dragonflies - CORRECT ANSWER - Formidable aerial and aquatic predators
Identify dragonflies as ancient insects (when, what, why) - CORRECT ANSWER -
Carboniferous period (360 - 300 mya)
Identify huge body size as the outstanding characteristic of animals (including dragonflies)
during the carboniferous period - CORRECT ANSWER - ...
Dates of major milestones in the history of life on earth, as indicated in the online learning
module - CORRECT ANSWER - Earth formed - 4.6 bya
Oldest rocks - 3.8 bya
Oldest fossils (= signs of life) - 3.5 bya
Cyanobacteria - 2500 mya
Algea - 1200 mya
Cambrian Explosion - 545 mya
First dinosaurs - 230 mya
First birds - 150 mya
Dinosaur extinction - 65 mya
Modern humans - 200,000 ya
Identify interesting and 'unusual' events in the history of earth - CORRECT ANSWER -
"Snowball" - ice ages: the whole earth froze and created a giant ice ball, which was caused by the
Pangea, meaning instead of there being seven continents, there was only one supercontinent.
Cambrian explosion: The animals alive during this period are what interested me the most, they
almost look like crustaceans, but they are a million times bigger, which astonished me. One of
the animals described had five eyes!
,Recall environmental characteristics of the Carboniferous period - CORRECT ANSWER -
At the beginning of the carboniferous period, it is assumable that once again we have a giant
continent with only small break offs, and just complete water at the two poles. The continent
begins to expand to the poles, but one side of the earth still has no land and strictly just water.
Oxygen during this tie was at a pearl or beginning to peak ,eating that this was a time where
oxygen on the earth was higher than the eras before.
Relate changes of O2 levels in the atmosphere to biological events in the history of life -
CORRECT ANSWER - Oxygen concentration is a key physiological control on body size,
especially in groups like flying insects that have high metabolic oxygen demands. So, the more
oxygen in the air, the more consumption of oxygen by the dragonflies, increasing their organs,
and overall their size.
Recognize that all O2 on earth stems from biological processes - CORRECT ANSWER -
O2 was created by cyanobacteria, which are green bacteria that harvest energy from the sun and
create sugars, while O2 was the byproduct. (Photosynthesis)
Recognize the geology of earth has been dramatically changed by biology - CORRECT
ANSWER - 60% of earth's minerals are biogenic, which means the earth's minerals use
oxygen produced by life; they were generated through life.
Describe the mechanism of diffusion at the level of single particles - CORRECT
ANSWER - From high concentration to low concentration
Describe the pattern observed due to diffusion at the level of many particles - CORRECT
ANSWER - ...
Explain how the behavior of single particles explains the observed pattern at the many particles
level - CORRECT ANSWER - Each particle moves on its own, going from a naturally
high concentration to a low one, but this occurs by random particle movements. The particles
naturally go to a lower concentration, but this happens only by the particles colliding with other
moving particles. This then leads us to be able to predict, generally, where the molecules are
going, because as we stated, we cannot predict the exact movement of each individual particle.
, Diffusion - CORRECT ANSWER - • Movement of molecules from an area of high
concentration to an area of low concentration
• Driven by Brownian (thermal) movements of molecules
Particles move randomly on both sides
• There are more particles at the side of high concentration
• Thus, it is more likely one will move from high to low concentration
• This continues until there is an even number on both sides
• Random motion of individual particles result in the net flow of particles from high to low
concentration
Each molecule: - CORRECT ANSWER - Moves randomly (not directed to low
concentration)
Unpredictable
Never stops
Net (= total) movement of all molecules: - CORRECT ANSWER - From high to low
concentration
Predictable
Stops when reaches equilibrium
Diffusion over distance - CORRECT ANSWER - T = x2/ 2D T = time X = distance D =
diffusion coefficient (depends on temp)
• e.g. O2 in water: 10 micro(m) in 12 ms
1 mm in 2 mins
1 cm in 3 hours
1 m in 4 years
Diffusion is very efficient within most cells (1 - 100 micro(m) but is not useful over greater
distances)
