Summaries

Building up and breaking down

As the earth´s crust moves the rocks can change, it can change its position going up, down or sideways. rocks can also change their shape. They can be bent, squeezed, twisted or broken.
The most comon type of mountain is the fold mountain, fold mountains is made mostly of layyers of rocks. a fold black mountain is made of huge lifted blocks of rocks. Plateaus are offten found next to mountains ranges. They where probably formed in teh same way as the mountains.

Another forces that transform earth ´s surface are weathering an erosion. Weathering is the breaking down of rocks into small pieces and erosion is picking up and removal of particles.
Weathering result on building new soil. the slow soil development is called soil horizon. horizon A is the top soil, horizon B is subsoil and horizon C is weathered.

Lift carry and drop

Along mountain tops and hillside, weathering breaks down rocks into sediment. The sediments can be fine bits of clay or largerparticles such as sand or gravel. Gravity is always pulling things down and with erosion create material deposition.

glaciers are like big buldozers that puch down large cuantities of materials creating valleys chaping earth´s surface, like Valley Glacier.

Rock Cycle

To begin with, rocks are solid .They make Earth's crust . A mineral is a naturally occuring solid with a definite structure. Each mineral is made up of a particular elements. A rock can be one mineral or a mixture of minerals. The properties include hardness , a measure easily a mineral can be scratched. Other property is luster, how a mineral reflect light . The streak of mineral is its colar when it is ground into power. 

The recycling machine works something like this. Liquid  rock material solidifies either at or below the surface of the earth to form igneous rocks . Uplifting occurs forming mountains made of rock. The exposure of rocks to weathering and erosion at the earth's surface breaks them down into smaller grains producing soil. The grains  are transported by wind, water and gravity and eventually deposited as sediments. This process is referred to as erosion. The sediments are deposited in layers and become compacted and cemented  forming sedimentary rocks. Variation in temperature, pressure, and/or the chemistry of the rock can cause chemical and/or physical changes in igneous and sedimentary rocks to form metamorphic rocks. When exposed to higher temperatures, metamorphic rocks may be partially melted resulting in the creation once again of igneous rocks starting the cycle all over again.

Geologic time

Superposition is a series of rocks layers being the top layers the youngest and the lower ones the oldest.

Fossils are remains trace or imprints of living things preserved on earth ´s crust. Fossils tell us what kind of creatures lived in the past. They are also clues to know how their surroundings looked like.

	PALEOZOIC	MEZOSOIC
	CAMBRIAN		CENOZOIC
	ORDOVICIAN	TRIASIC
PRECAMBRIAN	SILURIAN		TERTIARY
	DEVANIAN	JURASIC
	MISSISSIPIAN		QUATERNARY
	PENNSYLVANIAN	CRETACEOUS
	PERMIAN

Heredity

Is the passing of traits from one generation to the next. The word generation refers to parents and their off-springs being each one generation itself.

Heredity refers to all organisms, plants animals or even bacteria. humans have inherited traits too, hair and color are example of human inherited traits.

Pollination is the transfer of pollen grains from the male part of a flower to the female part of a flower. There are two pollination processes, cross and self pollination.

Predicting traits

Probability means how likely it is that something will happens .The probability that something will happens

can be calculate with mathemathics.Probabilities can be written in as ratios .They also be written as

percentages or as fractions. In genetics you can use a kind of table to help predict inherited traits.

The table is a Punnett Square . A Punnett Square is a table used to predict the outcome of crossing

different forms of a trait , such as Mendel s experiments .In a Punnet Square , letters are used to represent

Mendel s factors for each trait .

* A capital letter stands for dominant

factor , and a lowercase letter stands

for the recessive factor .

* To make a Punnett Square , draw a

large squre and divide it into four smaller

squares .Write the parent s factors for

the trait outside the square.

* Fill in each square with the letter above

it  and the letter to the left of it . The square

combinations of  traits in the offspring.

A Punnett Square shows the different combinations of factors offspring can inherit from their parents.

The combinations of factors inherited by offspring is not exactly the same thing as the physical appearance

of the offspring.


How Heredity Works

To understand how this factor works , first find out where it is .It is actually a molecule.This molecule is found in one of the parts of a cell.  Which part do you think a factor is in ? Every cell surrounded by a cell membrane . Inside the cell membrane is a fluid called cytoplasm . In the center of the cytoplasm is the cell nucleus , which contains chromosomes .Chromosones are made of molecules. A human body cell contains 46 chromosomes . A rabbit body cell contains 44 chromosomes  . Every  organism has its own number of chromosomes. A human sex cell comtains 23 chromosomes.

Mitosis is the division of the nucleus while a cell is dividing into two indentical cells . During mitosis a second set of chromosomes is formed inside the cell.

Meiosis is the division of a nucleus , resulting in sex cells with half as many chrmosomes as in other cells.  In this process a cell divides twice . The nucleus divides twice as well.

A  genes is the portion of  a chromosomes  that controls a particular trait . Genes  contains the imformation needed for a cell to function .

Genes are portions of a long , complex molecules called deoxyribonucleic acid or DNA . DNA contains the codes that tell each cell how to operate.

Using What We've  Learned

Do you have any dominant traits ?
Some common traits in people that follow simple patterns of dominant and recessive traits are :

Dominant Traits                                          Recessive Traits

* Freckles                                                                                        * No Freckles               

* Long Eyelashes                                                                             * Short Eyelashes 
* Free Earlobes                                                                               * Attaches Earlobes


                                                                                          
Sickle - Shaped Cell
Some inherited traits in people are not as simple as dominant or recessive . One example is the shaped of red blood cell. Red blood cells carry oxygen and nutrients to all parts of the body. Let R stand for the gene for round red blood cell . R° stands for the gene for sickle - shaped cells.

* Most people have the gene pair RR . That is , they have only round red blood cell.
*  People with R° R° genes have only sickles-shaped cells. 
* However , people may also inherit one R gene and one R° gene.