Ch13-life-in-ocean-grsn-text

Ch13-life-in-ocean-grsn-text - Chapter 13 LIFE IN THE OCEAN...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
13 Chapter LIFE IN THE OCEAN   MAIN CONCEPTS Life on Earth is notable for both unity and diversity:  diversity   because there are perhaps 100 million different species (kinds)  of living things on Earth;  unity  because each species shares the  same underlying mechanisms for basic life processes. Living things are not exempt from the second law of  thermodynamics, but they can delay that inevitable descent into  disorganization because the transformation of energy in living  things allows a temporary and local remission of the second  law.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 Chapter LIFE IN THE OCEAN   Producers assemble food molecules using energy from the sun  (photosynthesis) or from energy-rich inorganic molecules  (chemosynthesis). Productivity is expressed in grams of carbon bound into  carbohydrates (food) per square meter of ocean surface per  year (gC/m2/yr). Primary producers—autotrophs—are organisms that synthesize  food from inorganic substances by photosynthesis and  chemosynthesis.
Background image of page 2
13 Chapter LIFE IN THE OCEAN   Producers and heterotrophs (consumers) interact in often- complex energy relationships called food webs. All of Earth’s organisms are composed of about 23 of the 107  known chemical elements. Four elements—carbon, hydrogen,  oxygen, and nitrogen—make up 99% of the mass of all living  things. Living organisms are supported and sustained by huge  nonliving reserves, and there is a large-scale transport of  elements between the reserves and the organisms themselves.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 Chapter LIFE IN THE OCEAN   The great bulk of the ocean lies in perpetual darkness. The  upper part of the photic (lighted) zone sustains photosynthetic  producers. Cold water can hold more gas in solution than warm water. Seawater tends to buffer solutions, preventing wide swings in  pH (acid-base balance). Diffusion, the movement of substances from regions of high  concentration to low concentration, and osmosis, the movement  of water through membranes, are important processes in  moving substances within and between living cells.
Background image of page 4
13 Chapter LIFE IN THE OCEAN   The environments populated by marine life may be classified by  their physical characteristics. Marine organisms are naturally classified by their physical  characteristics and by the degree to which they resemble other  organisms.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 Chapter LIFE IN THE OCEAN   An ecosystem is the totality of the  environment encompassing all chemical,  physical, geological and biological parts. Ecosystems function by the exchange of matter and energy.
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 27

Ch13-life-in-ocean-grsn-text - Chapter 13 LIFE IN THE OCEAN...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online