Download Part 1: The Factors of Life!

Part 1: The Factors of Life!
Study the pictures below. Can you name the abiotic factors as well as the biotic factors?
Abiotic Factors
Biotic Factors
A “factor” is something essential to the existence of life. And we know that all living organisms require
some non-living (abiotic) factors to survive.
List several factors an organism needs to survive:
1. _______(moderate temperature) __________
How many of these factors are non-living,
or abiotic? _____3_______
2. _____________(water)___________________
3. ____________(nutrients/minerals)_________________
4. _____________(sunlight)_________________
What kind of environmental changes might alter the availability of these resources? (Hint: Consider
weather cycles, or the effect of human community development.)
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
How Organisms Obtain Energy and Satisfy Nutritional Needs
Introducing: The Producers
Autotrophs (“auto” means _self_ and “troph” means _nourish ) use photosynthesis (or
chemosynthesis) to build their plant bodies and produce ATP, stored energy. Oxygen is a byproduct of
photosynthesis. Write the chemical formula for photosynthesis below:
___6 CO2____ + __12 H2O____+ sunlight
Carbon dioxide
+ water + sunlight
___C6H12O6__ + _6O2_ + _6H2O_
Glucose + oxygen + water
Introducing: The Consumers
Heterotrophs- “hetero” means __________
1st order heterotroph/primary consumers are herbivores that eat plants.
2nd order heterotroph/secondary consumer are carnivores that eat herbivores.
3rd order heterotroph/tertiary consumers are carnivores that eat carnivores.
An omnivore is a consumer that eats both plants and animals.
Introducing: The Decomposer
A decomposer is a consumer that breaks down and releases nutrients from dead
organisms
(e.g. bacteria, protozoans, fungi)
QUESTION: Can a tertiary consumer be an herbivore?
Other nifty terms to describe feeding habits: (provided by the teacher)
Detritivore- consumes dead organic/plant matter
Piscivore- eats fish
Planktivore- eat plankton
Scavenger- eats carrion (dead animals)
Food Chains and Food Webs
Trophic level (feeding step in a food chain)
How do the abiotic factors affect biotic factors?
Although there are a number of different abiotic factors that affect producers, two we will look at are
temperature and sunlight.
1. The effect of temperature on the rate of photosynthesis (i.e. food production).
Enzymes are an important factor in photosynthesis. But they are sensitive to temperature. The enzymes
will not function if temperatures are extreme. Enzymes will reduce or even halt their processes in
extremes. Study the graph below and answer the questions following.
http://fhs-bio-wiki.pbworks.com
1)
What happens to the rate of photosynthesis (y axis) as the temperature climbs to 25 degrees
Celsius?
______________________________________________________________________________
______________________________________________________________________________
2) Once the temperature exceeds 25 degrees Celsius, what happens to the photosynthesis
production?
______________________________________________________________________________
3) Compare the ineffectiveness of photosynthesis on either side of the graph. Make a statement
about the “curve” as you compare both sides. ________________________________________
______________________________________________________________________________
4) Considering that photosynthesis is food production (glucose) for the plant, what can you
generalize about temperature and the health of plants?
______________________________________________________________________________
______________________________________________________________________________
2. The effect of sunlight on the rate of photosynthesis.
We know that there are producers (plants) in aquatic environments, just as there are
on terrestrial (land) biomes.
Name several aquatic plants:
__________________________
________________________
__________________________
________________________
So often we think of trees as the oxygen producers for living organisms, when in reality, it is the oceans’
algae that produces at least half, if not more of our atmospheric oxygen. The green areas below
indicate the highest degree of high biologicigal productivity.
Part 2: Let’s look at aquatic factors!
Types of Aquatic Systems
Have the students give local examples of each in your locale if possible.
1) Flowing- rivers and streams
2) Wetlands- swamps, marshes, bogs
3) Water bodies- ponds, lakes, ocean, estuaries
Identify the components and characteristics of an aquatic environment. How can we define a pond
environment as it differs from the aquatic environment of a deep ocean trench?
Question: What are some characteristics that make them different?
1. __light________________
2. __temperature_________
3. __salinity_____________
4. __oxygen level_________
5. __flow_____________________
Factor #1 Light
We have established that sunlight is essential for photosynthesis to occur. But as light strikes the
surface of the water, much is reflected back. The more movement made by the water, the more light is
reflected off of the surface and back into the atmosphere. Most visible light waves are absorbed within
33 ft. (10 meters). Blue and violet waves of light travel deepest, giving most water its color. Identify
below the two zones of aquatic environments, one with sunlight and the other without.
1. Photic zone - ___the zone in which there is sufficient sunlight for photosynthesis to take place in
aquatic plants, such as phytoplankton. ______________________________________________
Microscopic
phytoplankton
is an essential
food source to
many marine
animals.
Brown kelp is a
large type of
algae common
in ocean waters.
2. Aphotic zone ____the region of perpetual darkness where there is insufficient sunlight for
photosynthesis to occur. _________________________________________________________
Light intensity increasing in
shallower waters
Food production
(increasing)
Food production
(increasing)
Knowing what you do about photosynthesis, can you sketch the curves on the following graphs?
Light intensity decreasing in
deeper waters
Factor #2 Depth
So what about the depths of aquatic environments? Is it lifeless and useless? Not at all! Most things that
die sink to the bottom where decomposers or ______detritivores___________ recycle those nutrients.
If the recycled nutrients are on the bottom, how do they bring nourishment to plant life near the
surface?
Upwelling- Temperature and currents will cause the recycled nutrients on the bottom of the ocean to
move up and come to the surface. This provides nutrients for the phytoplankton, and thus for the
entire ecosystem!
Even though there is no visible light, one really cool adaptation is the ability to produce
bioluminescence, the emission of light. It is a characteristic of some bizarre looking deep sea fish as well
as some insects on land.
____Bios ____is Greek for “living” and ___lumen____ is Latin for “light”. Fireflies and deep water fish
both produce light when the pigment, luciferin, is activated by the enzyme luciferase.
One example is the angler fish that uses it for bait.
http://www.youtube.com/watch?v=UXl8F-eIoiM Planet Earth web bite!
Factor #3 Temperature
We know that the visible light translates into heat. There are three temperature zones in ocean water.
The surface layer, or mixed layer, is the warmest as it is most affected by the surrounding air and
sunlight, as well as wind and rain. The shallow coastal surface waters in the tropics can reach 100°F
(38°C). The second layer, the thermocline, is where the water temperature drops as the depth
increases. In the third layer, the deep-water layer, water temperature decreases slowly as depth
increases. Water temperature in the deepest parts of the ocean is averages about 36°F (2°C).
The location on the earth makes a difference as well.
•
Light intensity is higher at lower ___ latitudes ___ (closer to the equator)
•
The more light absorbed by the water, the __higher___ the temperature
From "Ocean Talk" by Naval Meteorology and Oceanography Command
1) Where would you expect to see temperature fluctuate , or change, the most?
Surface waters due to changes in light intensity and wind convection/currents
2) Where would you expect to see more constant temperatures?
At great depth and nearest the poles (north and south).
Factor #4 Salinity
Salt water becomes more concentrated in areas where the sun’s intense heat causes water to
evaporate. This denser surface water forms currents as it falls to the lower levels of the ocean
and rises again. These are called thermohaline currents. ___ ”Thermo” ____ means heat, and
“___ ”haline” ____ means salt.
Bill Nye demonstrates:
http://www.youtube.com/watch?v=w_8mw-1HYFg&feature=related
Most organisms are adapted to a specific, narrow range of salinity.
Estuaries are very special in that the organisms that live within this environment must be
tolerant of a constantly changing level of salinity. Animals that have the ability to adapt are blue
crabs and oysters. Mangroves are short trees with roots that not only tolerate change in
salinity, but they also provide protection for nesting animals among their many exposed roots.
Other creatures of the estuary are mud worms (bristleworms), stalk-eyed mud crabs and
cockles, a small burrowing shellfish. Scallops, a popular seafood live in this constant flux of
salinity.
Factor #5 Dissolved Oxygen
Oxygen is an essential element required for aerobic ___respiration___ Remember, respiration has the
opposite chemical reaction to photosynthesis. Write the formula for respiration below:
C6H12O6 + 6O2
6 CO2 + 6H20 + energy (ATP stored energy)
ATP provides energy to all organisms. Life on earth would cease to exist without it.
The concentration of ___dissolved_______ __oxygen_____ (DO) varies in water. Using prior knowledge of light, temperature and depth, hypothesize about the concentration of DO in various levels
of the ocean:
Where do you think most of the oxygen is located in the ocean waters? _________________________
Here are two hints:
Hint #1- Wind currents and waves stir up the surface water.
Hint #2-Decomposers are doing a lot of work at depth (cellular respiration) and there are typically no
plants (no photosynthesis)
Surface oxygen from the air is constantly being trapped in the upper surface area of the ocean by wind
and wave activity.
Sunlight in the surface area allows for the growth of plant life. Their product is ___oxygen____.
Whereas, ____detritivores_____ consuming dead matter in the ocean depths, utilize oxygen for
respiration.
Fill out the table below to characterize and define the different types of aquatic systems. Use the
following terms: low, moderate, high, variable
Aquatic
System
A shallow
River/Stream
Swamp/Bog
Characteristic
Light
Depth
Temperature
Salinity
Dissolved
Oxygen
The bottom
of a deep
Lake
Shoreline of
a Salt Marsh
Estuary
The surface
of the Ocean
The bottom
of the Ocean
Thought Questions!
1) How might the salinity change in an estuary after a heavy rainfall?
2) How might the salinity of an estuary be different in different locations, such as the mouth of an
input river or at the pass leading to the ocean?
3) Would you expect the dissolved oxygen to be higher or lower at the head or bottom of a river?