Honors Biology

Module 10 Ecology

January 23, 2014

Class Challenge

CREATIVE HAT DAY

Quiz

The Geological Column

Ecology

Is the study of the interactions between living and nonliving things.

We are going to study how organisms are specifically designed to interact with other organisms as well as their physical surroundings.

EcologyIs divided into subgroups:

• Population: A group of interbreeding organisms coexisting together.

• Community: A group of populations living and interacting in the same area.

• Ecosystem: An association of living organisms and their physical environment.

• Biome: A group of ecosystems classified by climate and plant life.

These groups go from narrowest to broadest

1. Population is the narrowest, as it includes only one species (is a set of organisms that can interbreed).

2. Community is made up of one or more populations.

3. Ecosystem includes not only several populations, but also their physical surrounds.

4. Biome is a very broad classification, encompassing several ecosystems.

Life is a balance

In order to assure that life can continue on any part of the earth, there must be a critical balance between the organisms living in an ecosystem and the nonliving chemical and physical processes that play critical roses in the support of life.

Rabbits in Australia

From your reading in Module 10 (pages 299-300) please explain what happened to the grasslands of Australia.

Energy and Ecosystems

All organisms need energy in order to survive. Almost all of the energy ultimately comes from the sun.

Autotrophs convert energy from the sun for food. (some autotrophs use chemicals)

Autotrophs are called producers.

Producers produce food for themselves and other creatures.

Herbivores: Eat only plants and get their food directly from producers, they are called primary consumers.

Trophic Levels (Fig. 10.1)

Primary producers are eaten by ---- Secondary producers

Carnivores (eat other carnivores) are called

Tertiary consumers.

This is commonly referred to as a food chain.

Trophic Levels

Hawk – Tertiary Consumer

Snake- Secondary Consumer

Mouse – Primary Consumer

The plant - it is the lowest on the food chain.

Food Web

Trophic levels of some animals can change. A more complex diagram called a food web better illustrates feeding relationships among organisms in an ecosystem.

See figure 10.2

Why are trophic levels so important in an ecosystem?

1. Every living organism must have some type of preditor or the organism will overrun its ecosystem.

2. Trophic levels track energy as it moves through the ecosystem.

1. When energy comes into the ecosystem, it is usually through the sun. (first and highest level of energy). The energy of sunlight is used by producers to make food for themselves.

2. When producers are eaten by primary consumers, energy moves to the next trophic level.

3. Secondary producers eat primary consumers, energy moves up to the next trophic level.

How is energy lost?

Each time energy moves up a trophic level, a lot of that energy is lost.

1. When cellular respiration occurs, some energy is lost in the form of heat. When a fox eats a rabbit, it does not eat the whole thing; it eats only the meat and fat. The fur, skeleton, etc. of the rabbit are not used by the fox. All that energy is lost because it does not end up being used by the consumer.

Ecological pyramid

Figure 10.3

In previous modules we have discussed decomposers. Decomposers feed at all trophic levels. Dead plants, dead primary consumers, dead secondary producers and dead tertiary consumers.

They have their own unique trophic level and it is hard to fit them into a food chain or food web.

Nevertheless, they are vitally important to an ecosystem. As decomposers eat, it is creation’s way of making sure that the energy “lost” from trophic level to trophic level is not lost in creation.

Mutualism

Is the relationship between two or more organisms of different species where all benefit from the association.

Pages 305-309.

Mutualism

In Module 3 remember we learned about the termite that eats the wood but cannot digest the cellulose and the protozoa lives in the gut of the termite that eats the cellulose that the termite cannot digest. This keeps the termite alive while providing ample food for the protozoa.

Mutualism

In Module 4 we read about the mutualistic relationships between algae and fungi, which are called lichens.

Also the mutualistic relationships between plants and fungi, which are called mycorrhizae.

Mutualism

Clownfish and the

Stinging tentacles

Of sea anemones

Biologists believe

That the chemical

Makeup of a layer of mucus that covers the clownfish is very similar to the sea anemone mucus. This allows the fish to swim without harm.

The clownfish benefits by the anemone as it is swimming/hiding in the anemone as it is protected from predators who would be stung.

The anemone benefits because the motion of the clownfish swimming near or in the anemone tantalizes predator fish creating food for the anemone.

Ecosystems

http://youtu.be/Ot_KmOTYfRA

Food Webs

Homework

Read Module 10 pages 309 – 324

Answer OYO questions 10.1 – 10.4

Answer Study Guide questions a-I and 2-6

Complete lab book “Food Web”

Class Challenge

Quiz: Explain the “Taxonomy” of Ecology

Explain Food Webs.