« previous next »

Author Question: The habitable zone is the area around a star where: A) planets with life have been found. B) ... (Read 66 times)

luvbio

  • Hero Member
  • *****
  • Posts: 623
on: Jul 27, 2018
The habitable zone is the area around a star where:
 
  A) planets with life have been found.
  B) human beings could live.
  C) the Greenhouse Effect is possible.
  D) a planet could have an atmosphere.
  E) temperatures are suitable for planets to have liquid water.

Question 2

Why does detection of abundant free oxygen in an atmosphere suggest life is present? Does its absence prove life could not be present?
 
  What will be an ideal response?


lkanara2

  • Sr. Member
  • ****
  • Posts: 329
Reply #1 on: Jul 27, 2018
Answer to Question 1

E

Answer to Question 2

Oxygen is highly reactive, and unless quickly replaced by photosynthesis, would soon disappear into surface rocks, as it has on Mars and Venus. However, life on Earth certainly evolved before it released the abundant present oxygen, and on other worlds, photosynthesis may not have evolved. Yet other forms of life may thrive using methane or hydrogen sulfide, all energy processes found here as well.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

luvbio

  • Hero Member
  • *****
  • Posts: 623
Reply #2 on: Jul 27, 2018
TY


lkanara2

  • Sr. Member
  • ****
  • Posts: 329
Reply #3 on: Jul 27, 2018
You're welcome


« previous next »
 

Did you know?

About 80% of major fungal systemic infections are due to Candida albicans. Another form, Candida peritonitis, occurs most often in postoperative patients. A rare disease, Candida meningitis, may follow leukemia, kidney transplant, other immunosuppressed factors, or when suffering from Candida septicemia.

Did you know?

The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.

Did you know?

Everyone has one nostril that is larger than the other.

Did you know?

Approximately 25% of all reported medication errors result from some kind of name confusion.

Did you know?

Fewer than 10% of babies are born on their exact due dates, 50% are born within 1 week of the due date, and 90% are born within 2 weeks of the date.

The most abundant elements found in living organisms The most abundant elements found in living organisms
Location of the Planets Relative to the Sun Location of the Planets Relative to the Sun
Having a time zone map located near the telephone will assist you when making long distance calls ou Having a time zone map located near the telephone will assist you when making long distance calls ou
Gossip and ridicule increase the status insecurity of this time of life. Gossip and ridicule increase the status insecurity of this time of life.
Should We Prolong Life at all Costs? Should We Prolong Life at all Costs?
Video: The 4 steps of translation Animation

For a complete list of videos, visit our video library