02/9/11 (Wednesday, February 9th)

-Announcements: BIO DAY TOMORROW! (in the auditorium, apparently its a great movie.)

-Homework: Study for Unit 7: Evolution Test.

Today in class we took very brief notes on the dates and timelines of how animals branched off of each other to become different species.

We also took notes on how researchers can tell how long an animal has been dead by how long its been in the ground and which of the two animals ages are approximately.

Mr. Paek also went over the Quiz as a review for the test.

We also did a brief lab today.

-Lab Explanation:

To measure the variations of the same species of grasshoppers for the length of there legs.

lab can be found on page 233. The title is "Variation in Grasshopper Legs"

-Directions:

Use a metric ruler to measure one femur on each grasshopper.(look at figure 1 to locate the exact spot of where to measure.) Use the same points on each femur you measure. The measurements should be accurate to the nearest 0.1 cm.

Point of the Lab:

The point of the lab was to show how even though animals are the same species they can come in different sizes, in this case, for grasshoppers it was the femur.

-Side Notes:

-Bio Day Tomorrow.

-TEST FRIDAY!(study)

Danny your the next scriber.

Tuesday, February 8

-Announcements: There will be a bio day on Thursday, February 10th

-Homework:

+Read 26.3 (notes are optional, but recommended)

+Finish Lab

+Review Quiz Tomorrow (won't count as a grade, just to help study)

+Unit 7: Evolution test FRIDAY (study!)

I. Notes

Today we took notes in our student handout To Be Or Not To Be notes packet. The notes were taken under roman numeral V. Human Evolution. The blue is what we added. They are as follows:

V.Human Evolution

First Humans...

-Ape-human split- (5-7 million years ago)

-Australopithecus "Lucy"- Found in Africa

Got name from beatles song

Oldest and first species of humans.

-Homo Habilis- "Handy Man"

Had the ability to use tools

2.5 MYA (million years ago)"

-Homo Erectus first to migrate- (1.8MYA)

Walked upright

Used Fire

-Homo Sapiens- 200,000 mya

-Homo Sapiens- Made excellent tools

Good hunters

Had burial rituals

Primates...

-Binocular Vision (3D)

-Flexible forelimbs and shoulders

-Problem Solving Ability

II. Next We Did A Lab

Brief Notes Taken Before Lab:

-Brow bridges less prominent

-Skull capacity went up

-Jaw shape went from "U" to "V"

-Sagittal crest decreased

Lab Explanation:

We worked on a short lab today. The lab can be found on UP pages 42-47. It is titled Evolutionary Changes In Primates.

-What you have to do:

Based on the diagram on p.43 (Figure 1) & p.46 (Figure 3+4) we recorded data onto a chart (p.45). Using the chart we answered questions on page 47. In order to fill in the chart you needed a protractor & a ruler (using CM side). The procedure part on p.42&44 explained how to measure & analyze the diagrams. Filling in the chart was a little difficult but the procedure explains it pretty well.

-Main Point of Lab:

The main point of the lab was to observe the evolutionary changes from gorilla to australopithecus to modern human. By observing the three skulls, jaws, and pelvic features it is easy to link the evolutionary similarities and note the differences.

+Similarities:

The biggest similarities between the two is the jaw structure. They have the same amount of teeth and the "U" and "V" shapes are quite related as well. Their skull structures, overall, resemble one another clearly

+Differences:

In contrast, the individual brain area is very different among the three. The human brain area is much larger and the skull is much smaller than that of the gorilla and australopithecus. The pelvis between the human & australopithecus are much smaller & wider (bipedalism) than a gorilla (walks on all fours).

-Lab Conclusion

So as you can see, the lab basically enforces Darwin's discoveries in that a species evolved from a common ancestor.

III. Scribe Post Conclusion

Thats pretty much all that we did today. Don't forget to go over the lab q's and studyyy!!

The next scriber will be...Danny. Ha! sorry. unless he has a game that night. then jordan.

Scibepost for October 13, 2010 by Amreen M(=

Today we had shortened classes because of late arrival, so for 35 minutes, Mr. Paek taught us about Mitosis and we took notes. He also gave us a worksheet with some of the notes and pictures of the stages of mitosis.

First, he explained that the reason we don't have a bunch of big cells in our body is because with small cells, theres more surface area in terms of volume so its easier for gases to get exchanged.

Mitosis-the life cycle and division of a cell

Mr. Paek explained to us that interphase, which are the three big parts of this cycle, takes much longer then metaphase, which are the four small parts. Interphase has three parts: the G Phase, S Phase, and the G2Phase, and it basically is preparing the cell to divide. During interphase, the individual chromosomes cannot be distinguished and appears as a dark mass of material called chromatin.

Interphase- Each chromosome is replicated, consisting of two identical "sister" chromatids; the DNA of each chromosome replicates at the end of this stage.

After he explained Interphase for a couple minutes, he went on to mitosis, which has four stages. Phrophase, Metaphase, Anaphase, and Telephase. Mr. Paek said that when he was learning the cell cycle in school, he used an anagram called IPMAT, which stands for Interphase, Prophase, Metaphase, Anaphase, and Telephase. These stages are also in order.

Prophase-The stage when chromatin condsenses into chromosomes, centrioles seperate, spindle fibers form, the membrane gets broken, and the nuclear envelope disapears. This is a picture of a cell in the prophase stage.You can tell its in the phrophase stage because the membrane has holes in is and is beginning to break.

Metaphase-The chromosomes line up at the center of the cell. Each chromosome is connected at the centromere to the spindle fibers.

Anaphase-The paired chromosomes split into individual chromosomes and are moved apart.

Telephase- The chromosomes gather at opposite ends of the cell and then split. The spindles are broken apart, the nuclear envelope reappears, and the nucleus divides

We also briefly talked about Cytokinises, which takes place after Telophase. Cytokinesis is when the cytoplasm pinches in half and each daughter cell has duplicate chromosomes. Here is picture summing up everything:

After we were finished taking notes, Mr. Paek let us watch the Last Lecture for the last two minutes of class. Our homework is to read, highlight, and complete page 40-43 in our Unit Packet. These pages are our Mitosis Pre-Lab for the lab that we will be doing tomorrow

The next scriber is..MALIHA!=D