sections 6.2 and 6.3 reflection

This is what I learned about what the function of membranes is. I learned that the plasma membrane is composed of phospholipids. This plasma membrane is what holds the contents of a eukaryotic cell inside the cell. I learned that proteins are what allows the membranes to perform certain functions and these proteins also help cells communicate with one another. I also learned that membranes can permit certain substances and deny others access to the interior of the cell.
What I have found difficult about what I have studied are the contents in section 6.3. Some concepts I can understand but others such as hypertonic, hypotonic, and isotonic go right over my head. Also, I simply have no idea how to understand the pictures on pg. 120. After reading it several times, the whole idea seems to completely evade me.
Structure is related to function in cell membranes because membranes give the cell its rigid form and the membrane also serves as a regulator, allowing only certain substances inside the cell. This mean that the plasma membrane is very fluid and is constantly moving, allowing for substances to pass through in the first place. This membrane or boundary, holds many proteins that perform specific functions for the cell. Also, because the unique structure of the plasma membrane, the proteins that are lodged in the membrane are able to communicate with other cell's proteins.

JELLO HOMEWORK

Jello is essentially gelatin, which is processed collagen, which is a structural protein in animals

collagen is extracted from boiled bones and intestines of animals

the trapped liquid give gelatin its wiggle, but the protein allows for it to keep its shape

water is the biggest component in Jello

gelatin is made up of amino acids in a chain

Jello has little nutritional value

collagen makes up some of the protein in the human body

collagen is composed of three polypeptide chains that are held together by hydrogen bonds

introduction rough draft part 3

PART 3

The purpose of our lab is to determine what different amounts of water does to the germination of a yellow dent corn seed (Zea mays indenta). Through the observation of 5 separate germination tests we will be able to tell what amount of water is optimum for proper germination of the seed. There will be a total of 4 variables in our experiments, 3 of which will remain constant throughout: soil, light, and temperature. Each day the seeds will be watered with the appropriate amount in order to tell us which daily amount is best for fastest germination. All the corn seeds used will be used from a commercial seed packet. If a yellow dent corn seed is exposed to 2 tablespoons of water per day, then it will germinate at a faster rate than any other amount of water.

attributions

http://www.agry.purdue.edu/ext/corn/news/timeless/germemergreq.html   8/30/10

http://www.wyffels.com/pages/early_corn_development.html  8/30/10

corn-yellow dent seeds: germination

• dent corn will germinate and emerge slowly and unevenly when the soil temperature is below 50F
• enough moisture must be available in the soil for the seed to consume 30% of its total weight in water in order for germination to occur
• the first part of the seed to emerge is the "radical"
• the ideal growing point is usually 1-1.5 in. below the surface of the soil
• if the soil is too wet then the seed could decay
• soil should be between 70-85F for ideal germination