Author Question: Discuss why marine phytoplankton are generally smaller and more ornate than their freshwater ... (Read 262 times)

luminitza

  • Hero Member
  • *****
  • Posts: 555
Discuss why marine phytoplankton are generally smaller and more ornate than their freshwater counterparts.
 
  What will be an ideal response?

Question 2

Variations in Earth's orbit that influence long-term climate changes include ________.
 
  A) the shape of Earth's orbit (eccentricity)
  B) the tilt of Earth's axis of rotation (obliquity)
  C) the wobbling of Earth's axis of rotation (precession)
  D) eccentricity, obliquity and precession



Christopher

  • Sr. Member
  • ****
  • Posts: 316
Answer to Question 1

The photic zone is the upper portion of the ocean in which light levels are sufficient to support photosynthesis. In the open ocean, this layer is 100-200 meters deep. If autotrophic planktonic organisms sink below 200 meters, then they die. Marine diatoms are much smaller than freshwater diatoms; their increased surface area to volume ratio keeps them afloat. Additionally, marine diatoms have ornate spines that increase surface area. Many freshwater diatoms live in habitats where light penetrates to the bottom so sinking is not problematic. Freshwater diatoms lack the ornate spines frequently observed in marine diatoms because light penetrates to the bottom of the pond, stream, or puddle where they live.

Answer to Question 2

D



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

luminitza

  • Hero Member
  • *****
  • Posts: 555
Both answers were spot on, thank you once again



Christopher

  • Sr. Member
  • ****
  • Posts: 316

 

Did you know?

Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.

Did you know?

According to research, pregnant women tend to eat more if carrying a baby boy. Male fetuses may secrete a chemical that stimulates their mothers to step up her energy intake.

Did you know?

Atropine, along with scopolamine and hyoscyamine, is found in the Datura stramonium plant, which gives hallucinogenic effects and is also known as locoweed.

Did you know?

When intravenous medications are involved in adverse drug events, their harmful effects may occur more rapidly, and be more severe than errors with oral medications. This is due to the direct administration into the bloodstream.

Did you know?

Drug abusers experience the following scenario: The pleasure given by their drug (or drugs) of choice is so strong that it is difficult to eradicate even after years of staying away from the substances involved. Certain triggers may cause a drug abuser to relapse. Research shows that long-term drug abuse results in significant changes in brain function that persist long after an individual stops using drugs. It is most important to realize that the same is true of not just illegal substances but alcohol and tobacco as well.

For a complete list of videos, visit our video library