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Saturday, January 29, 2011

Apologia Biology, Module 10, Ecology

M10 Recap blog post at Sahm-I-Am
Quizlet Vocabulary Game, M10

(1) p. 299-301, Introduction
Ecology is the study of the interactions between living and nonliving things -- the way living things live in a specific environment and how they survive, what they eat, consumers, producers, etc.  All the consumers will not eat up all the producers.  If the food starts to get scarce, like a particular animal that is food for another consumer, the animals that are consumers will move to find a source of food.  Then the animal that is food will gradually populate the area once again.  The same thing happens with plants that animals eat.  Things will stay balanced in this way.

►►Watch this video about Population Ecology.
Click Animation.

Certain animals only live in one specific type of environment.  This could be where it is hot and dry, or cold, or wet and rainy, or warm and rainy, or other combinations.  These also depend on the season.
This is called a biome.
►A few general kinds of biomes are aquatic, deserts, forests, tundra, and grasslands.
There are different types of each of the general biomes that I listed.  For example, there are tropical rainforests, temperate deciduous forests (leaves turn each fall), or temperate coniferous forests (cone-IF-er-us: cone-bearing trees).

►See the temperate zones at this link, highlighted in pink.
Temperate refers to a region not too near the north pole or south pole, but not too near the equator either.  They have hot summers and cold winters.
There are two temperate zones, one in the middle of the northern hemisphere (hemi = half), and one in the middle of the southern hemisphere.  Think of someone who is even-tempered.  In the middle.  =)

What is an Ecosystem?  (population, community)

►See a lake ecosystem. (source)
►A sagebrush ecosystem. (source)
►Specific biomes are found in specific locations in relation to the poles and equator, such as the temperate forests mentioned above.

A biome is made up of ecosystems. 
An ecosystem is categorized by climate, animals, and plant life.  Ecosystems are made up of communities, which are groups of populations living and interacting in the same area.
Read the definitions on p. 299. 


In your text, you will read about rabbits that were brought into Australia, and that there was no consumer, no predator for rabbits.  Therefore the rabbits overpopulated Australia, and it took over 50 years for anyone to figure out how to control the rabbit population.
There must be balance in ecosystems, and God created natural predators, called consumers.  If left alone (no one trying to "fix" things), nature will stay balanced.

In your Study Guide, question # 2 asks, "When fruits or vegetables are imported into the U.S. from a foreign country, they are always very closely inspected for insects, even though the vase majority of insects are not really harmful.  Why is the inspection done?"
I was watching something this morning about a plague that initially affected the Eastern Roman Empire in the years 541-544, AD.  It was a bubonic plague, and, occurring during the reign of Roman Emperor Justinian I, was called the Plague of Justinian.
(not "The Plague" or the Black Death of Asia and Europe during the 14th century)
The origin of the Justinian Plague was thought to have been carried by fleas on rats that came into Constantinople on grain boats.  The Plague was believed to have killed as many as 5,000 a day in Constantinople at the peak of the epidemic (about 40% of the inhabitants), and eventually thought to have caused the deaths of as many as 100 million people.
I didn't find anything about whether this affected the ecology (I'm sure it did), but while I was watching this documentary, I thought of this question in the Study Guide.  Makes one think, doesn't it?


(2) p. 301-305, Energy and Ecosystems

All living things need energy.  They need food.  Plants, animals, and other organisms need food.
►If a plant or other organism makes its own food, it is an autotroph.  Autotrophs are eaten by other animals, therefore an autotroph is a producer.  It does not eat other organisms.  
Look at the bottom of the diagram.  →
►An organism that eats a producer is a primary consumer.  (Primary meaning first.)  These are herbivores.
►An organism that eats primary consumers is a secondary consumer.  These are carnivores because they do not eat plants.
►A carnivore that eats other carnivores (secondary consumers) is a tertiary consumer.  (TER-she-air- ee)
*An omnivore would be both a primary consumer and a secondary and/or tertiary consumer.

These relationships of producer and consumers are called trophic levels.

You have probably seen this demonstrated in a food chain.

But it is a little more complicated than that.  A hawk can eat a snake, and the hawk would be a tertiary consumer.  But if the hawk eats a mouse, the hawk will be a secondary consumer.  Remember what I said earlier about an omnivore?*
This can be demonstrated by a food web.
What organisms are in a particular food web is determined by what kind of biome, or more specifically, what ecosystem we are talking about.

--In your textbook, the arrows flow from the consumer to the animal or plant being consumed.
--In these pictures, the arrows flow in the direction of energy going from the organism being eaten, to the one doing the eating.
►See this ocean food web.

Some great links I found posted at Applie's Place:

It is important to realize that each trophic level requires a lot of food for energy from the previous one.

It is important to remember that energy is lost each time it moves up a trophic level in an ecosystem.
If you need to, re-read the last few paragraphs on p. 303 to understand this, then watch this video.

You also need to understand the significance of biomass.  Biomass is the measure of the total dry mass of organisms within a particular region.  If an animal eats something with a lot of water in it, it will probably need to eat more to sustain life.
Look at the diagram on p. 304, similar to the trophic pyramid above with the ocean life.
On p. 304, the producers are many times more than the primary consumers.  If you look at the width of the primary consumer level, it is about 3 times as wide as the secondary consumer level.  And the secondary consumer level is about 3 times as wide as the tertiary consumer level.
These percentages are not the same as the diagram above in the ocean life example.
Each ecosystem will not be exactly the same as another ecosystem.

Last we need to mention decomposers.  Decomposers tend to feed at all trophic levels, so they were not included in the trophic pyramid.  Decomposers take care of the energy that is "lost" between trophic levels.  God makes sure that the energy that is "lost" gets back into creation by decomposition.


(3) p. 305-309, Mutualism
Those who believe in the "survival of the fittest" do not like mutualism.  According to macroevolution, species should compete with one another for survival.  This video is just one example of mutualism between unlikely couples.  You can see more odd couples here.  =)  


(4) p. 311-313, The Water Cycle
Watershed -- an ecosystem where all water runoff drains into a single body of water.
transpiration -- evaporation of water from the leaves of a plant



(5) p. 314-315, The Oxygen Cycle
Through photosynthesis, plants take in carbon dioxide and give off oxygen which humans and animals breathe.
Carbon dioxide is also converted to oxygen by other means, and vice versa.


(6) p. 316-322, The Carbon Cycle
When animals and humans breathe, we take in oxygen and give off carbon dioxide.
Other means of producing carbon dioxide include decomposition and burning fuel.
Although carbon dioxide is constantly being produced, it is also constantly being taken away.  Most carbon dioxide is used up by photosynthesis.  Some carbon dioxide is dissolved into the ocean, where some organisms use it to form their shells.  There are other ways too.
Carbon dioxide has an important job -- it keeps the earth warm.  This is called the greenhouse effect.
Have you ever been in a greenhouse?  It is very warm! 

When certain gases trap heat here on earth (that would otherwise escape the earth and go into outerspace), this is called the greenhouse effect. 

Some people say we are having warmer winters, but if they would think about it, not every place on earth is having warmer winters.  Some are having colder winters and/or even cooler summers.  Therefore it is not "global" warming.
Also, you can’t just look at one year.  If you look at a larger time span, like the Figure on p. 319, you will see the overall warming is very slight, and fluctuates often.  Look at the numbers on the left of the graph and see how many total degrees the temperature has risen.

►Also look at the site of Dr. Roy Spencer, former NASA scientist.
Scroll down to see the latest global temps.
Temperatures were up in 2010, but when I first posted this, I said we were due for some cooling down.  See the graph?   
Look at the left of the graph for the total rise in average temps since 1979.  Not even ½ of a degree.  =) 

Since carbon dioxide can be produced by burning fuel, some people think that we are getting too much carbon dioxide into the air, and that this causes excess global warming.
Watch this video by Answers in Genesis, part 1.


(7) p. 322-325, The Nitrogen Cycle
The Nitrogen Cycle is very fascinating to me! 

I love the cow!  =)

Not only do animals eat plants with nitrogen, secondary consumers and tertiary consumers eat other animals to get their nitrogen.  Also, dead plants and animals, as well as waste, put nitrogen back into the soil for plants. 

Here's a video about the nitrogen cycle in water.


  1. Thank you so much for sharing your experience and knowledge. My daughter had to drop her awesome co-op class and this site is helping me to fill in the gaps as I work to catch up a bit.


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