NEW UNIT!!!! REPRODUCTION

this week we started a new unit: reproduction!!!! We started the new unit with a few questions.....

1. How do organisms reproduce??

I said: Organisms reproduce by when a male and female have sexual contact. A sperm needs to fertilize the ova or egg to reproduce. Males identify if the

organism is male or female. Females only have X chromosomes males xan have X or Y. If a X matches up with an X then the organism is a female if an X matches up with a Y then the organism is a male.

2. How do cells reproduce?

I said cells reproduce by splitting in half, this process is called mitosis. Mitosis is a process of cell division which results in the production of two daughter cells from a single parent cell. The daughter cells are identical to one another and to the original parent cell.

Mitosis has a process or steps:

The steps to mitosis:

Interphase: Cells may appear inactive during this stage, but they are quite the opposite. This is the longest period of the complete cell cycle during which DNA replicates, the centrioles divide, and proteins are actively produced. For a complete description of the events during Interpha

se, read about the Cell Cycle.

Prophase: During this first mitotic stage, the nucleolus fades and chromatin (replicated DNA and associated proteins) condenses into chromosomes. Each replicated chromosome comprises two chromatids, both with the same genetic information. Microtubules of the cytoskeleton, responsible for cell shape, motility and attachment to other cells during interphase, disassemble. And the building blocks of these microtubules are used to grow the mitotic spindle from the region of the centrosomes.

Prometaphase: In this stage the nuclear envelope breaks

down so there is no longer a recognizable nucleus. Some mitotic spindle fibers elongate from the centrosomes and attach to kinetochores, protein bundles at the centromere region on the chromosomes where sister chromatids are joined. Other spindle fibers elongate but instead of attaching to chromosomes, overlap each other at the cell center.

Metaphase: Tension applied by the spindle fibers aligns all chromosomes in one plane at the center of the cell.

Anaphase: Spindle fibers shorten, the kinetochores separate

, and the chromatids (daughter chromosomes) are pulled apart and begin moving to the cell poles.

Telophase: The daughter chromosomes arrive at the poles and the spindle fibers that have pulled them apart disappear.

Cytokinesis: The spindle fibers not attached to

chromosomes begin breaking down until only that portion of overlap is left. It is in this region that a contractile ring cleaves the cell into two daughter cells. Microtubules then reorganize into a new cytoskeleton for the return to interphase.

January 7th, 2010

i think the second day of our new unit we started to look at a slice of an onion root under a microscope.

We saw a few interesting things under the microscope. A few cells had two nuclei in 1 cell, some would have a bunch of little dots in 1 cell, others would have just 1 nuclei in a cell.

december 19 2009

this really stinks because i have no notes in my journal from this week ill try my best to remember though.

this week we basically went through a review on what we need to know on the test. ( that ill probably fail) we had to make a essay i guess is what you can call it and we had to write about organelles and how it would be in a city.

this week was a review and we did an activity showing this.....

i really dont know what to write about so i guess ill just leave it to this

december 14, 2009

this week we started learning about DNA and RNA!! We learned about ADANINE, THYNINE, CYTOSINE, AND GUAYNINE. '

ADANINE ONLY GOES WITH THYNINE AND GUAYNINE ONLY GOES WITH CYNINE

LATER ON WE PLAYED A GAME I GUESS IS WHAT YOU CAN CALL IT AND WE GOT TO SEE HOW THE PRODUCT IS MADE?

DNA MEANS DEOXYRIBOSENUCLEICACID

RNA MEANS RIBOSENUCLEICACID

rna is like half of dna

the one on the right is dna and th left is rna. RNA has one backbone and Dna has two. Dna starts with a certain base its ATCG and RNA is AUGC. OH i forgot to mention that U STANDS FOR URACILE. URACILE IS ONLY IN RNA AND IT ONLY GOES WITH ADANINE.-

ATP= energy.

homework

i have no clue what to right because i have no clue what week we are on but ill give it a try.



this week we learned about respiration, photosynthesis, and fermantation.



photosynthesis- the synthesis of complex organic materials, esp. carbohydrates, from carbon dioxide, water, and inorganic salts, using sunlight as the source of energy and with the aid of chlorophyll and associated pigments.


PHOTOSYNTHESIS
h2O + CO2 + LIGHT -------> C6 + H12 + O6 + 02


RESPIRATION:

C6 + H12 + 06 + O2 ------> CO2 + H2O + ENERGY

FERMENTATION--- RESPIRATION WITH OXYGEN


SUGER --> C6 + H12 + O6

WE ALSO LEARNED ABOUT DNA.

- ITS TORNADO SHAPED
-LARGE MOLICULE
-NUCLEUS IS WERE ITS FOUND
THE REAL WORD FOR DNA IS DEOXYRIBONUCLEIC acid

i have no clue what week it is--- SCIENCE HW

this week we started on what an organism was. we had a disscussion in class, and my opinion of a organism was that an organism is a living thing.For example animal, plants, etc. and example of a non-organism is... minerals and water.

this is what i thought since we were talking about potato cells as our example!


an organism is ------> living
a potato is ----------> living
potato cells are in the ----> potato a potato is ----> living ------living means---> organism


Finally we came to a conclusion an organism one or more cells that can independantly sustain life.

after we finished our discusion the next day we learned about prokaryotic and eukaryotic.

a prokaryotic cell is a cell that has no nuclus, a ribosome but no membrane,e. coli and bacteria are examples of prokaryotic.

eukaryotic- is any organiasm that has a nuclus is complex, has membane organelle .
ex. plant cell -> potato
cheek cell -> animal cell


then later we started on working on photosynthesis we did a expirament with why plants need photosynthesis.
we learned about atoms, typles o0f sugers( like glucose and galacose ) we learned about alot of things this week.

i dont have to blog!!!!!!!!!!

I DON'T HAVE TO BLOG!!!!!!!!!!!!!! ( fyi this was supposed to be for last weeks hw)

science hw 11/5/09

this week we didn't do alot, because it was only a three day week, but.....

this week so far we have learned about organelles and their functions.

we made a chart and a Venn-diagram with 3 circles.

this week we also learned about paramecium's, a yesterday we tried to look for some paramecium in pond water. we looked under a microscope my partner was Yolanda.

i will add some more stuff tomorrow( Friday)