October 6th, 2011

Today in class we did day 2 for the egg demo. Since our egg broke yesterday we redid the experiment for day 2 and our results were:

• still the same shape


• that the egg was soft


• bubbles on the shell


• the shell was getting thinner so you could see the yolk a little bit


• the egg was slightly yellow as a result of the thin shell
  http://www.greensim.com/lemonade/egg1.JPG
  
  
  

We also went over the Mitosis notes from last night's homework.
-To find the notes log onto moodle and go to the biology page, then scroll down to Unit 2- Cells R us and click on the folder called class notes unit 2 and then click CH 7mitosis notes

In class we started the Mitosis lab in the UP packet on pages 53-56. We will finish the lab later in class.

Homework:

• Study for unit test on Tuesday


• work on lab UP pages 53-56


• Internet activities on pg. 4 (review)

Up next is Lydia

October 5th, 2011

In class today we first checked our Egg Mitosis DEMO. The egg was soaked in vinegar and we had to draw a picture and describe it. The shell was being eaten away by the vinegar so it did not make a noise when it was touched. It was soft instead of hard. There were bubbles all over it because the shell was being eaten away and there was no color change.

Next in class we did a lab about osmosis and diffusion on pages 41-42. Under a microscope, we looked at elodea leaves with regular tap water and 6% salt water. The plant cells looked normal in the tap water. The chloroplasts were all on the outside of the cell, the cell membrane was close to the wall, the vacuole was visible and the nucleus was seen. In the 6% salt water, though, the cell membrane condensed and the vacuole shrunk. Here is a cartoon showing what happened from http://waynesword.palomar.edu/images/elcell7a.jpg:

As can be seen, the water left the vacuole and it could not be seen, but is still present.

We also drew a picture (similar to these pictures) of what we saw in each type pf water. We also labeled what we saw. We then answered questions from the lab on page 42 by ourselves, and then went over them in class together.

We filled out page 43, which was about osmosis and different water concentrations inside and outside of cells.

At the end of class we watched an intro movie to mitosis.

Homework: Read Chapter 8 (pages 121-129), Mitosis notes from Moodle, and read mitosis labs from pages 53-60.

Next Scribe: Maddy

Oct. 3, 2011

Today we finished the notes on the cytoskeleton and began notes on the cell membrane. There is a quiz tomorrow on everything we've learned so far in the section. There is also a lab tomorrow. The homework is to read pages 37-39 in our UP and draw a picture of the lab.

Here are some basic overviews of what we learned.

Intermediate Filaments

• ropelike protiens
• anchor organelles

Microtubules

• straight, hollow tubes made of protiens called tubulins
• provide rigity and shape to the cell
• tracks for organelle movement
• guide chromosome movement in cell division
• move cilia and flagella

Cilia-propel protists

Flagella-propel some types of cells, long "tail"

Microtubule structure

• form a 9+2 arrangementto
• to move cilia or flagella, dyniens grap onto an adjacent microtubule doublet
• basal bodies and centrioles have identical structures

Plasma Membrane

membranes of a cell

• plasma membrane-outer membrane
• endomembranes-smooth and rough ER, golgi, vacuole,lysosome
• membraneous envelope-nucleus chloroplast mitochondria

membrane features

• semi-permeable, allow some substances to pass through, but not others

membrane structure

• two layer membrane called phospholipid bilayer, composed of protien and lipids
• lipids called phospholipids
• contain 2 fatty acids, not 3, fatty acids are hydrophobic
• contain phosphate groub in place of 3rd fatty acid

flexibility

• membranes not flexible, rigid
• protiens move freely in membrane plane
• called fluid mosaic

diffusion and osmosis

diffusion-the tendency of molecules to move from a higher concentration to a low concentration until equilibreum is reached

Passive transport

• diffusion across a membrane
• cell uses no energy
• selectively permeable membrane
• osmosis-passive transport of water across a semipermeable membrane
• in osmosis water moves across membrane not the solute

Hyper tonic-solution with a higher concentration of solute and a lower concentration of water

hypotonic- solution wit ha lower concentration of solute and a higher water concentration

isotonic-solution with equal solute concentration

Effect on living animal cells

• osmoregulation-control of water balance
• animals must use this when exposed to hypertonic or hypotonic environments
• fish use gills and kidneys to keep too much water out

Effect on living plant cells

• most plants thrive in a hypotonic environment when there is more water
• plants become wiltedin isotonic environment

next-Dana

9/26/11

Today in Biology we did the Enzyme lab. In the lab we used Catalase,hydrogen Peroxide, water, Sucrose solution, HCI solution, distiled water, NaOH sulution and three different temperatures to test the different speeds of reations by measuring bubbles made in each test tube. There were four different parts of this experiment.
in each of the four peices of the experiment, three testubes studied

Part I. Does catalase break down one specific substrate?

In each of thees three experiments 1 CM of one substance and 5 CM of another substance were added to each other in their test tubes. After the second substance was added to the first it was immidiatley swirled to mix and then after 20 second of waiting, each test tubes bubles were measured.

Part II. Effect of temperature on Enzyme activity

This experiment is very similar to the first as in measurments of substsnaces added but after the first substance was added to the three test tubes each one was put into one of three temperature controled areas. An incubater, a fridge, and boiling water. After 15 minutes the second substance was added to the tube, then swirled and measured.

Part III. Effect of Enzyme Concentration Catalase Activity

The first testube followed the same procedures as all the test tubes in Part I. Tube 2 followed the same instructions except the first mark was two centemiters and the second was six. As before, tube 3 follows the same procedures except the measurments were 3 and 7 centimeters.

Part IV. Effect of pH on Catalase Activity

The three test tubes in this last part only are simmilar to the other parts as in they were still swiredl to mix and waited 20 seconds before measuring but this time, before the swirl the tubes must si with the sullotion out for a minute and the measurments were different. the measurments were 1 CM, 3 CM, 7CM. Each tube had 1 CM of Catalase and two other substances.

The h0mework for tomarrow is pre lab on pages 23-26

Next Scribe: Jackson