Tag: Science

STEM Challenge

Hsin-Yuan ElainaLeave a comment

What building techniques make the tower stronger?

Making a strong base can help the tower to be stronger and be balance. If the base is not still, than the tower can not stand straight and will fall down. Also, using the string as a support will also help the tower to be stronger. The materials to make the tower is spaghettis, and using more spaghettis to make one pillar.

Does the placing of the marshmallows affect the strength of the tower?

The placing of the marshmallow affect the strength of the tower because when the marshmallow is a little bit more right or left, than the tower will not balance and fall down.

Could you build a stronger tower with more of the same materials? What alternative materials would be better?

By using the same materials, I think we can make a stronger tower by effectively using the string. Using the string as a support, to help the part that is too light, and balance the tower. Our tower is very strong, it didn’t break into two pieces. The problem is that it is unbalanced. So using the string can help the tower.

Does the size of the base alter the strength of the tower?

The size of the base will change the strength because the stronger the base is, the taller and stronger the tower will be. Also, I think if the base is taller, it will be more balance.

How do you think you worked as a group? Did you assume different roles? Did all groups work in the same way?

In our group, everyone give ideas and help to build the tower. We separate the work into 4 parts, and everyone do their part, so we can build the tower faster.

What is Force?

Hsin-Yuan ElainaLeave a comment

What is force? Force is a push or a pull, it include size and direction. The unit of force is n, which represent newton, and named by the scientist Isaac Newton. Force occur on object, meaning that you when you push, an object must receive it. But when force is happening, it doesn’t mean that motion will also occur. Motion is when an object move. Force is separated into two kinds, balance and unbalance.

When a force to object is balance, the object will not move. Like the example shown in the below picture, the table will not move because of the reaction force of the table and the weight of the metal block.

When a force is unbalance, the object will move. For example, because there are unbalance force (80n and 40n), the force will bigger n will make the wagon move the the direction it is pushing/pulling.

 

Citations:

http://eschooltoday.com/science/forces/balanced-forces.html

http://eschooltoday.com/science/forces/unbalanced-forces.html

Mitosis and Meiosis

Hsin-Yuan ElainaLeave a comment

There are two ways of making new cells, mitosis and meiosis. They are both making cells, but one is making same cell and the other is making different cell.

Mitosis:
For mitosis, its goal is to form a genetically identical “daughter” cell, and mitosis is how cell divide. Mitosis go through 5 phases, Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis. First, in early prophase, it is the setting up for the division. The chromosome will start to condense, and mitotic spindle will form. Also, the nucleolus will disappear. In late prophase, or prometaphase, the chromosome finish condensing and the nuclear envelope breakdown. In metaphase, the chromosome line up at metaphase plate, and the spindle checkpoint will make sure that all the chromosomes are at the metaphase plate. In anaphase, the sister chromatids separate from each other and are pulled towards opposite ends of the cell. In telophase, the cell is almost finish dividing, two new nuclei form. Cytokinesis, the division of the cytoplasm to form two new cells, and this is the final stages of mitosis.

Meiosis:
For Meiosis, its goal is to make more cells, but different kind of cell. To divide into more cells, meiosis need to go through two step process, meiosis I and meiosis II. In meiosis I, there are also prophase, metaphase, anaphase and telophase. In prophase I, homologous chromosomes pair up and exchange fragments, which is also known as crossing over. In metaphase I, homoloue pairs line up at the metaphase plate. In anaphase, homologue separate to opposite ends of the cell, and sister chromatids stay together. In telophase I, newly forming cells are haploid, and each chromosome has two non-identical sister chromatids. In meiosis II, first, in prophase II, the cells are the haploid cell made in meiosis, and the chromosome condensee. In metaphase II, chromosome line up in metaphase plate. In Anaphase II, sister chromtids separate to opposite end of the cell. Lastly, in telophase II, newly forming gametes are haploid, and each chromosome has just one chromatid.

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