THIS IS THE BEGINING OF 3RD BIMESTER

SCIENCE QUIZ

FRIDAY, December 11, 2009!
only 5 B
study nervous system....
it will be oral quiz, not to everybody, really easy.... I will only ask you to give me examples of how the nervous system works!

VEGETAL CELL

PARTS OF THE VEGETAL CELL

Cell Wall
A rigid layer that supports and protects the plant cell.
Cytoplasm
A jelly like substance that contains many chemicals to keep the cell functioning.
Nucleus
The organelle that determines all of a plant cell´s activities and the production of new cells.
Cell Membrane
A covering that holds the plant cell together and separates it from its surroundings.
Vacoule
An organelle that stores food, water or wastes.
Chloroplast
organelles that make food for the plant cell.
Chromosomes
threadlike structure that contain information about the characteristics of the plant.
Mitochondria
organelles that release energy from food.

THE MICROSCOPE

A little bit of history
The first microscopes were invented in the early 1600s. One scientist who built and used an early microscope was Robert Hooke. In 1665 Hooke observed a thin slice of cork through a microscope. The tiny walled spaces he saw in the cork reminded him of tiny rooms. So he called them cells. Over the next 200 years, scientists learn more and more about the cells. They learn that the cell is the basic unit of structure and function of all living things.

REMEMBER THAT THEY ARE SOME LESSONS THAT YOU HAVE IN YOUR NOTEBOOK!

Animal Cell

this are the only parts that you need to learn!

VIDEOS

INTERESTING VIDEOS ABOUT CELLS!

HOW A WHITE GLOBULE CHASES A BACTERIA
http://www.youtube.com/watch?v=JnlULOjUhSQ

THE DIFFERENCE BETWEEN BACTERIA GROWTH AND CELL GROWTH
http://www.youtube.com/watch?v=7kIZ7PTRgVQ&NR=1

REMEMBER TO STUDY VEGETAL CELL FROM THE COPIES I GAVE YOU ON CLASS****

CELL ESTRUCTURE

Cell membrane: a covering that holds the animal cell together and separates it from its surroundings. Through the membrane the cell takes substances that it needs to live and it removes the ones it doesn’t need.

Cytoplasm: a jellylike substance that contains many chemicals to keep the cell functioning. Its responsible for the breathing, it produces proteins and sugars, transform nutrients, etc.

Nucleus: the organelle that determinates all of an animal cell´s activities and the production of new cells. This is the place where all the genetic information is located, it´s like a huge library.

Mitochondria: organelles that release energy from food.

The cell division is essential for life, because it allows to create a similar cell. Unicellular organism, like bacteria creates other bacteria. The pluricellulars organism are duplicating at all times. Not all cells duplicate at the same speed. For example the skin cells duplicate every day to substitute the dead ones, but the neurons can’t reproduce, when they die it´s not possible to create new ones.Plants and animals are different.

The most important difference it´s that plants make their own food and animals have to go and get it. The cells of plants and animals are also different. Vegetal cells have chloroplast in the cytoplasm; there is where the photosynthesis takes place.The size and the function of the cells are related.

BONE CELL (OSTEOCITO)

ITS RESPONSIBLE OF THE BONE FORMATION.

WHITE GLOBULE

IT PROTECT US FROM TOXIC MICROORGNISM

RED GLOBULE

TRANSPORTS OXYGEN TO THE BODY.

MUSCLE CELL

IS RESPONSIBLE OF THE MOVEMENT

NEURON CELL

THIS CELL IS REPONSIBLE FOR THE TRANSMISIONS OF THE NERVE IMPULSE

THE CELL

A cell is hundreds of times smaller than a sand dust, so we can only see it through the microscope. With the microscope we can see all kinds of cells, but we can also see one cell and its parts. On the XIX century, scientist found out that all tissue, animals or vegetables were formed with cells. They are different types and shapes of cells. The shape they have is related to the function they do, for example we have some sphere shape, like the ones on our blood called red globule.

The cells born, reproduce and die. During these stages they eat, breath, and eliminate toxic substances and consume energy. The cells are related to the outside world in many ways, they can react to the light, nutriments or toxic substances.

UNICELLULAR ORGANISMS

Unicellular Organism

Through the microscope we can observe with detail the parts of the living things. If we study plants and animals we can find small structures called cells. All the living things are formed with cells, so we have different kinds and structure of cells. Living things with one cell are called unicellular, for example ameba and bacteria; and they are responsible of breathing, eating, and reproducing. Then this unicellular organism transforms and makes more organisms with more than one cell, called pluricellular, for example animals and plants.

Bacteria: When the bacteria reproduce it’s divide to form two new cells. If they have enough food it can form two cells every 20 minutes. Many bacteria use water or air movement to transport to one place or another. Some bacteria live in the air or in the soil. Other live as parasite inside of living things. Most of the bacteria are hurtful to these living things. Some live in our digestive system, for example in the mouth, the stomach, the intestine and they help us to digest the food. From one kind of bacteria we can get some medicines, like antibiotics that help us against some diseases. Without bacteria, life in Earth will disappear really fast. We also have some bacteria that can make sick plants, animals and human beings they are called pathogen bacteria, for example tuberculosis, pneumonia, cholera. Even that they are so little bacteria can affect our health.

Other unicellular organism very important is the green-blue algae. They live in the water.
The amoebas are bigger organism than bacteria and they don’t have a definite shape. A lot of amoebas are parasites that live inside of animals or humans, and they cause sickness that could be dangerous if they are not treated on time. To prevent amoebas you can do some of the following tips:

1.Boil the water you drink for at least 10 minutes.
2.Disinfect fruits and vegetables.
3.Wash your hands before you eat and after going to the restroom.

Diversity and range of living things.

In earth we have a layer that goes from the highest mountains to the deepest oceans. It has 20 km. of thickness and it’s named Biosphere. In there we can find all the ecosystems; the natural ones (jungle, deserts, lakes) and the ones that have been changed like cities, towns, agriculture fields on rural communities, etc. The weather, types of soil, animals, plants and microorganism are important elements of each ecosystem. In all of this diversity, living things have characteristics of their own that allows them to adapt to the environment in which they live.

Even that they are so different, all living things share the same characteristics: they all need to breath and eat in order to have energy to grow and reproduce.Millions years ago, after Earth was formed, the first living things appeared.

They were small and very simple. As time passed, these organisms were multiplicated and became more different and complex. Today we have a great diversity of shapes and sizes of living things that live in almost all the places and climates of the world. All the living things that we can’t see at first sight we called them microscopic. Some examples are plants and animals that live in the water, soil, or air, and bacteria.

Thanks to the development of the microscope we are able to see these small living things. If we want to represent them in real size we could not do it. For that we need to amplify their size in a proportional way. In the case of big objects we need to make them smaller, we call this reduction.

A range tells us the number of times an object has been amplified or reduced and it can be expressed in centimeters.

ECOSYSTEMS

HERE IS A VERY INTERESTING VIDEO ABOUT ECOSYSTEMS, QUESTIONS ABOUT THE VIDEO COULD COME ON THE BIMESTRAL EXAM....
http://www.youtube.com/watch?v=AY8okmtEEEc

RURAL AND URBAN POLLUTION

RURAL POLLUTION:

1. WATER POLLUTION- WHEN WE THROW TRASH TO RIVERS, LAKES, SEA.

2.SOIL POLLUTION- WHEN WE BURN TRASH AND FARMERS FUMIGATE THE PLANTS.

URBAN POLLUTION

1. WATER- TRASH IN THE LAKES, ETC, WHEN WE DO LAUNDRY.

2. SOIL -BURN TRASH AND WHEN WE DONT SEPARATE THE FOOD, PLATIC, GLASS.

3. AIR- SMOKE OF FACTORIES, CARS, QUIMICHALS LIKE HAIR SPRAY, CIGARETTES, ETC.

* RURAL COMMUNITY = MORE PEOPLE = MORE CONTAMINATION *

NEW RELATIONSHIPS WITH NATURE

HOW TO AVOID POLLUTION:


- Water Pollution:
Use soap "zote" to do laundry.
Keep all water recipients closed.
Don´t throw trash to rivers, lakes, sea, etc.

-Air Pollution:
Don´t waste electric energy.
Use the bike or walk to go to close places.

-Soil Pollution
Don´t eat food wrapped so we can have less inorganic trash.
Separate the food in organic, inorganic and pet.

Mexico´s Ecosystem

In Mexico we have a lot of different plants and animals. Mexico´s flora (plants) is bigger than USA and Canada´s together, and it´s twice as big as the flora in Europe. The fauna are the animal species. Mexico has the biggest number of reptiles in the whole world. The second in mammals, the 4th in amphibians and the 7th in birds. This great diversity of flora and fauna it´s thanks to the different climate and territory, such as mountains, Cliff, coast, caves, etc.A species it´s a group of animals or plants that share the same characteristic. If we change ecosystems in a negative way we affect many species of animals that are in danger of extinction. Also earthquakes, climate changing, volcanoes, etc are natural changes in ecosystems that affect animal species.
Some of human action that affect ecosystems and the extinction of some species:

1. The growth of cities.

2. Pollution

3. Cutting trees.

4. When we move species from the original ecosystems, for example the cactus from the north of Mexico and Oaxaca.

5. Fishing and hunting.

6. Illegal hunting.

The 5 food groups!

remember to eat healthy!

** you have this information in english in your notebook**

How we change Mexico´s ecosystem

In Mexico, old civilizations such as olmecas, mayas, aztecas, etc were based on the modification of natural ecosystems introducing the agriculture. This is one out of two main activities, they did to change natural ecosystems. These civilizations that lived in our country gived the world more than 80 species of cultivated plants, such as corn, beans, chilli, tomato, vanilla, tabaco, etc. The second main activity old civilizations did, was to transformed a natural ecosystem into a place to live, to plant vegetables and to raise animals. In our days we have communities known as rural and urban communities.
A rural community is a small gruop of people, its more important activity is agriculture, and it has less than 2,500 residents. An urban community is bigger than a rural it has more than 2,500 residents and they use commerce and industry as a main activity. As the grow they expand and they change natural ecosystems by building houses, buildings, industries, pipes for w0ater, lines of communication, energy plants, etc. When an urban community reaches 50,000 residents or more it´s called a city.
Urban communities have more and a better quality of services, such as schools, medical center, transportation, access to clean water, electricity and more options to work as a profesional, than a rural community.in some cases this causes more traffic and pollutions wichs affects the residents.