NS4: UNIT 3: LIVING THINGS AND ECOSYSTEMS

 

UNIT 3: Living things and ecosystems

3.1.- Living things

-       Ecosystems are made up of living things( human beings, plants and animals) and non-living things( rocks, wáter and so on)

-       Living things can be multicellular ( many cells) or unicellular ( just one cell). 

Ø  Multicellular organisms

-       Cells are the building blocks of life.

-       Cells interact to form tissues.

-       Different types of tissue form organs.

-       Some organs form systems such as the digestive system.

-       Many systems form an organism.

Ø  Life functions 

-       The three life functions are: nutrition, interaction and reproduction.

 

1.- NUTRITION

- According to the type of nutrition organism can be: producers, consumers and decomposers.

·      PRODUCERS.- They are most of the plants. They make their own food through the photosynthesis. 

·      CONSUMERS.- They are animals which feed on other living things.

·      DECOMPOSERS.- They are fungi and bacteria. They fee don the remains of dead plants and animals.

2.- INTERACTION

- Living things interact with each other and the enviroment.

- When something happen, they respond to it.

- Animals use their sense organs connected with nervious system.

- Plants react to the light.

3.- REPRODUCTION

-       Reproduction is the process to create other living things.

-       There are two types of reproduction:

·      Sexually reproduction.- A female cell is joined to male cell. They are multicelular.

·      Asexually reproduction.- Unicellular organims reproduce by dividing their cells.

   3.2.-Classification of living things

-       Living things are grouped in five kingdoms: the protist kingdom, the monera kingdom, the fungus kingdom, the plant kingdom and the animal kingdom.

Ø  The protist kingdom 

-       Most of them are unicelular and live in water byt they can be unicellular.

-       Examples are algae and protozoa. 

Ø  The monera kingdom

-       They are unicellular and include bacteria.

Ø  The fungus kingdom

-       They can be unicellular ( yeast) or multicelular ( mushrooms).

-       Fungi are decomposers.

Ø  The plant kingdom 

-       Plants are multicellular.

-       During the photosynthesis, the release oxygen into the air. 

Ø  The animal kingdom 

-Animals are multicellulars.

- They release carbon dioxide during the process of respiration.

- They use their senses to interact with their environment.

 

3.-Elements of ecosystems

- An ecosystem include living things and non-living things that interact in a specific area.

- A change in it affects all the ecosystem.

Ø  Living things.

-       All the ecosystems have flora ( plants), fauna ( animals) and other living things such as fungi, protists and bacteria.

-       A population is a group of the same specie that live in an ecosystem.

-       A community is the interaction of many populations.

Ø  The physical components

- The physical components in a ecosystem are: air, water, sunlight, temperatura, climate and soil.

 

3.4.-Food chains and food webs

- All living things form food chains and food webs.

Ø  Food chains

-       Food chains are made up of producers, consumers and decomposers.

·      Producers.- They use energy from the Sun to make their own food though the photosynthesis.

·      Consumers.- There are three types:

                          -Primary consumer.-Hervibores and omnivores. Example: rabbits.

                          -Secondary consumer.-Carnivores and omnivores. They eat primary.Example: foxes.

                          - Terciary consumer o predators.-They eat secondary. Predators Hunt their prey.                                                 Example: Eagle.       

·      Decomposers

-       They decompose matter and feed on the remains of dead organisms

Ø  Food webs

-       The food chains can be connected together to form a food web.

Ø  Other relationships 

-Organisms compete and cooperate in a ecosystem.

- Example: plants compete for the Sun.

- Example: Ants and bees cooperate together to survive.

3.5.-Types of ecosystems

-There are many types of ecosystems: 

Ø  Forest

-       Forest have got many trees in the same area. They can be:

·      Deciduous forest.-They lose their leaves. Flora: oaks and beches. Fauna: squirrel, wild bear.

·      Coniferous forest.-There are evergreen trees. Flora: pine trees. Fauna: foxes and deers.

·      Mediterranean forest.-Along the Mediterranean Sea. Flora: cork oaks. Fauna: eagles and foxes. 

Ø  Grasslands 

-       They are areas without water, just with grass. There are two types:

·      Savannahs.-They are warm. Herbivores live there such as giraffes and zebras.

·      Temperature grasslands.- They are colder. Fauna: deer and rabbits. 

Ø  Deserts

         -Deserts are dry and hot.

         - Flora: cacti.

         -Fauna: reptiles.

Ø  Ponds

-       They are área of fresh water.

-       Fauna: fish, mollucs, frogs and algae. 

Ø  Shoreline

        -The shoreline is when sea and land meet.

        - Fauna: seagulls, types of algae and fish.

Ø  Urban ecosystems

        -Towns and cities include natural and artifitial elements.

        - Flora: trees, bushes, flowers in the Parks.

        - Fauna: domestic animals, rats, bacteria and protists.