Marine Bio Unit 1 Flashcards
What was James Cook’s contribution to marine science?
He conducted detailed mapping of the Pacific Ocean, collected data on ocean currents, and used a chronometer to measure longitude.
What was the Challenger expedition, and why is it important?
It was the first scientific expedition focused on oceanography, discovering 4,700 species and studying ocean depths and temperatures.
Where is the first major American marine laboratory located?
The Marine Biological Laboratory is in Woods Hole, Massachusetts.
What is sonar and how does it help in warfare?
Sonar uses sound waves to detect underwater objects, aiding in submarine detection.
Compare a scientific hypothesis to a scientific theory.
A hypothesis is a testable explanation, while a theory is a well-substantiated explanation based on extensive evidence.
What is a control in an experiment?
A control is an unchanged element used as a comparison in experiments.
Define a controlled experiment.
An experiment where only one variable is changed, while all others are kept constant.
What is a variable?
A factor that can change in an experiment. Independent variables are manipulated, and dependent variables are measured.
Name the 4 major ocean basins.
Pacific, Atlantic, Indian, and Arctic.
Which ocean basin is the largest?
Pacific Ocean.
Which ocean basin is the smallest?
Arctic Ocean.
What’s the difference between continental and oceanic crust?
Continental crust is thicker, less dense, and primarily granite, while oceanic crust is thinner, denser, and mainly basalt.
Compare active and passive continental margins.
Active margins are tectonically active with trenches and earthquakes, while passive margins are stable with wide continental shelves.
What occurs geologically at mid-ocean ridges?
Sea floor spreading occurs, where magma rises and creates new oceanic crust.
What happens geologically at trenches?
Subduction occurs, where one tectonic plate moves under another, recycling oceanic crust.
How are submarine canyons formed?
Submarine canyons are formed by erosion, often by underwater landslides or turbidity currents.
Describe the features of a central rift valley.
Rift valleys have active volcanoes, hydrothermal vents, and frequent earthquakes due to tectonic activity.
How do sediment build-up, seafloor age, and magnetic anomalies support seafloor spreading?
Older sediment is found farther from ridges, and symmetrical magnetic stripes show the periodic reversal of Earth’s magnetic field during seafloor spreading.
How were the Hawaiian Islands formed?
The Hawaiian Islands were formed by volcanic activity over a stationary hotspot in the Earth’s mantle.
Compare the asthenosphere and lithosphere.
The lithosphere is rigid and includes the crust and upper mantle, while the asthenosphere is semi-fluid and allows plate movement.
What is the difference between seamounts and guyots?
Seamounts are underwater volcanic mountains, while guyots are flat-topped seamounts eroded by wave action.
What is the composition of a water molecule?
A water molecule consists of two hydrogen atoms covalently bonded to one oxygen atom (H₂O).
Why do hydrogen bonds give water its unique properties?
Hydrogen bonds create cohesion and surface tension, and allow water to have a high heat capacity
What is heat capacity, and why is it important for marine life?
Water’s high heat capacity allows it to absorb and retain heat, stabilizing marine environments.
What is salinity, and what is the average salinity of seawater?
Salinity is the concentration of dissolved salts in water, with an average of 35 parts per thousand (ppt) in seawater. Sodium and chloride make up 85% of sea salts.
Where do dissolved substances in seawater come from?
Dissolved substances come from the weathering of rocks, volcanic activity, and atmospheric deposition.
