May 8th, 2012

Today in class: For the entire period, we worked on the What Nutrients are in Foods? lab (which is a separate packet from our regular unit packet). Mrs. Andrews also collected our "Design a Quiz" projects.

As far as homework goes: ~ Finish the nutrient lab that we worked on in class today
                                             ~ Work on review packets (TEST this thursday)

NEXT SCRIBE: Emily

As you probably all know, the purpose of the Nutrient lab was to test different foods (about 10 of them) for the presence of macromolecules (particularly starch, simple sugars, protein, and fats or lipids).  Because of the many different parts to this lab, your group of four (which were predetermined) had to divide up the work, so one person would find the results for each test, all working at the same time.  At the end of the period, the individual groups met with each other and exchanged data from each test.

In part 1 of the lab, your job was to set up the control for the various experiments.  The iodine test was first, where you observed the color change when with the mixtures starch and water, water and Lugol's iodine, and starch, water, ad Lugol's iodine all together.  If the mixture turned DARK PURPLE, that would be an indication that simple or complex starches were present (as it should have happened with the mixture of all three substances in this first experiment--the rest of the tests should have provided results that indicated there was no starch present).

To test for simple sugars, you had four different test tubes, two contained the mixture of glucose and Benedict's solution, and two contained the mixture of water and Benedict's solution.  One of each mixture was to be heated, and the other two were just supposed to be mixed together and observed.  Every one of the test tubes should have provided you with a negative result EXCEPT the test tube that had glucose and Benedict's solution that was heated--the color of that particular mixture should have been red, testing positive for glucose.

Next, you had to test for proteins.  The three test tubes in this experiment had the mixtures egg albumen, egg albumen and Biuret reagent, and water and Biuret reagent.  If the solution turned PURPLE, then this was an indicator for the presence of protein (the rest should have had negative results).


Lastly, you had to test for lipids.  One square of an unglazed brown paper bag should have been labeled "oil" and the second, "water."  You then had to wait until each substance evaporated to see whether or not the paper was translucent (light can go through, but one cannot see a clear image through the translucent substance)--if it was, lipids were present.  If not, than there were no lipids in the substance (distilled water tested negative, the oil tested positive).


After all of these "control tests," we had to perform the same experiments to test foods for each of the four different macromolecules (9 listed substances, and 1 from home).


To review, Benedict's test is an indicator for simple sugars, Biuret's test is an indicator for proteins, Lugol's iodine solution shows the presence or absence of starches, and an unglazed paper bag can be used to test for lipid (fats).


Think about this:


Which of the four macromolecules from the lab could be present in this chicken dinner?

This is basically what we did in the lab today--just think about what is in the food we eat and how the digestive system breaks it down/absorbs its nutrients! :)

May 7th, 2012

Today in class we took some practice quizzes and discussed the calorimetry lab.

Homework

• finish calorimetry lab, due tomorrow
• design a quiz, due tomorrow
• study for Tissues, Excretion and Digestion test, Thursday
• make sure you've read the chapters (21 and 22)

NEXT SCRIBE: Emma

Digestion Notes

There are 4 stages of digestion.

• Ingestion: eating food
• Digestion: breaking down the food you eat into small molecules that your body can use
• Absorption: the cells in the lining of the digestive tract take in the molecules and transport them throughout the body using the bloodstream
• Elimination: getting rid of undigested wastes

There are 2 types of digestion.

• Mechanical Digestion: physical processes like chewing and stomach churning
• Chemical Digestion: breaking down food with enzymes
• Hydrolysis: breaking down of polymers into monomers using the atoms from water
• Hydrolases: digestive enzymes that catalyze hydrolysis
• Enzymes: specific molecules that start chemical reactions

The alimentary canal is a fancy name for the digestive tract. It has hollow cativities where food passes through to be digested and absorbed (in red), accessory organs (in blue) and enzymes (in purple). The process of digestion starts in the mouth...

Mouth (oral cavity)

• chewing, lubricates food, swallowing into the pharynx (first part of the throat, before the split between the trachea and esophagus
• attached to the mouth are 3 pairs of salivary glands: release saliva (1 liter a day) and salivary amylase
• salivary amylase: breaks starches into sugars (maltose)

Esophagus

• muscular tube, uses muscle contractions called peristalsis to push food into the stomach
• no enzymes

Stomach

• stores food for 2 to 6 hours, can hold 2 liters of food and water
• muscular, churns food and gastric acid into a mixture called acid chyme
• contains gastric juice: pH of .8 to 2 (VERY acidic), hydrochloric acid (HCl) that kills bacteria and activates pepsin, pepsin: breaks proteins into amino acids, rennin: breaks down milk proteins
• stomach lining coated in mucus to protect itself from gastric juice, replaced every 2 to 3 days
• top of the stomach is closed off by the cardiac sphincter (esophageal sphincter in the picture) and the end of the stomach is closed off by the pyloric sphincter
• sphincter: muscular ring that contricts a part of the body until materials need to exit or enter

Liver

• produces bile: emulsifies fats, breaking big fat droplets into little fat droplets so they are accessible to enzymes
• bile is stored, concentrated and released by the neighboring gall bladder
• bile is secreted into the duodenum

Pancreas

• pancreatic juice: contains trypsin, lipase and amylase, neutralizes stomach acids in the duodenum
• trypsin: breaks down proteins into amino acids
• lipase: breaks down fats (lipids) into glycerol and fructose
• pancreatic amylase: breaks down starches into sugars (maltose)
• pancreatice juice is secreted into the duodenum

Small Intestine

• 2.5 centimeters wide, 6 meters long
• duodenum: first part of the small intestine, mixes pancreatic juice, bile and intestinal juice, 90% of digestion
• peptidase: breaks down proteins into amino acids
• maltase: breaks down maltose (disaccharide) into 2 glucose molecules (monosaccharide)
• sucrase: breaks down sucrose (disaccharide) into glucose (monosaccharide) and fructose (monosaccharide)
• lactase: breaks down lactose (disaccharide) into glucose (monosaccharide) and galacatose (monosaccharide)
• small intestine completes digestion and does most of the aborption
• villi: tiny projections on the lining of the intestine, increase surface area for absorption, absorbs nutrients and passes them into the sorrounding capillaries

Large Intestine

• 5 centimeters wide
• colon: majority of large intestine, absorbs water and excess salts
• appendix: small projection where the small and large intestines meet, no purpose in humans, possible function: to store extra "good" bacteria that the digestive system needs?
• rectum: end of the large intestine, stores wastes (feces)
• anus: final sphincter fo the digestive system

Pictures
http://science.howstuffworks.com/environmental/life/cellular-microscopic/cell2.htm
http://en.wikipedia.org/wiki/Mouth
http://www.umm.edu/patiented/articles/stomach_000329.htm
http://www.emedicinehealth.com/pancreatitis/article_em.htm
http://missinglink.ucsf.edu/lm/IDS_106_LowerGI/Lower%20GI/mainpages/smallintestine.htm

Wednesday March 21, 2012

Hi everybody!

Today we started out doing our Fast Plants lab (if you weren't here, get the data from your partner). After that, we worked in the Science Lab for the rest of class. First, we took Chapter 29 notes (and finished our notes packet), and then we just worked on our Wildland project. Here are the Chapter 29 notes (know the words in green):

• Sap is a watery solution that moves through the vascular system (since it is sugar, it moves through the phloem)


• Xylem - carries water and nutreients from the roots to the leaves and stems


• Phloem - transports sugar already made (like sap) from leaves to other parts of plants


• Plants get carbon dioxide from the air (through the stomata), minerals and water from the soil (through root hairs), and oxygen from the soil (through stomata)


• Remember that all minerals that enter a plant root are dissolved in water (it goes through the epidermis and cortex of the root, through the plasma membrane of root cells, and into the xylem)


• Mycorrhiza (fungi) help in absorption


• Macronutrients - needed in large amounts (carbon, oxygen, hydrogen, nitrogen, sulfur, phosphorus, calcium, potassium, magnesium)


• Micronutrients - needed in extremely small amounts (iron, chlorine, copper, manganese, zinc, molybdenum, boron, nickel - mainly components of enzymes)


• Deficiencies - quality of soil affects our own nutrition


• 3 types of soil bacteria:


• Nitrogen-fixing bacteria - converts nitrogen in air to ammonium


• Ammonifying bacteria - adds ammonium by decomposing organic matter


• Nitrifying bacteria - converts soil ammonium to nitrate - plants take this up


• Legumes (soybeans, clover, peas, alfalfa) have root nodules (contain nitrogen fixing bacteria called Rhizobium)


• Symbiotic relationship - bacteria have a place to live and receive carbohydrates/organics from plant. Plants get ammonium ions released into soil

• Transport of Water:


• Pulled up plant through transpiration (loss of water vapor from plant) through the stomata


• Cohesion - water molecules stick together, are pulled up together


• Adhesion - water molecules adhere (stick) to cellulose molecules in walls of xylem cells


• Molecules of water break off from the top of the "string" as they leave the leaf. String is kept tense and pulled upward as long as transpiration continues


• No energy expenditure by plant


• Called: adhesion-cohesion-transpiration mechanism


• Transpiration - greatest on sunny, warm, dry, and windy days


• Unless rehydrated, plant could eventually die


• Leaf stomata can help plants adjust transpiration rates - controls opening by changing shape


• Open during day and closed at night, saving water. May close during day if plant is losing water too fast


• The Transport of Sugars:


• Phloem sap moves in various directions in plant


• Phloem moves sugar from a source (leaf) to a sink (root or fruit)


• Plant hormones - control plant growth and development, affect division, elongation, differentiation of cells


• Auxin - produced by apical meristem (at the top), stimulates growth of the shoot, causes cells to elongate


• Cells elongate (more auxin) on dark side of stem, causes stem to bend on opposite side (toward light)

• Requires certain concentrations - too much inhibits stem elongation


• Usually, it inhibits roots (except in high concentrations it can elongate roots)


• Ethylene - a gas which triggers aging responses - fruit ripening, dropping of leaves (when one apple is spoiled, it releases too much ethylene, which spoils the whole bunch)


• Cytokinins - growth regulators, promote cell division in roots, embryos, and fruits, stimulates growth of axillary buds (branches and bushy - why cytokinins are used by growers of Christmas trees)


• Gibberellins - stimulates elongation and cell division in stems, can influence fruit development, used in grapes


• Abscisic Acid - slows growth (ex: seed dormancy, especially during adverse conditions), during drought causes stomata to close during wiliting, preventing further water loss


• Photoperiods - what plants use to detect the time of year; relative lengths of day and night


• 2 groups:


• Long-night plants - chrysanthemums and poinsettias, flower in late summer, fall or winter, when night lengthens (also called short-day plants)


• Short-night plants - lettuce, iris, cereal grains, flower in late spring or early summer, when night are brief (also called long-day plants)


• Some plants are unaffected by photoperiod, like dandelions (night-neutral)

Homework

1. Wildland project (due Tuesday, April 3rd)


2. Study for Chapter 28-29 Quiz - TOMORROW!!


3. EC UP 61-62 and 63-64


4. Study for Unit 9 Test - FRIDAY!!

Next Scribe: Michael

Friday March 16th, 2012

As usual, we started out today's class with the "Fast Plants" lab (spending about 5 minutes on it). Right after, we continued working on our "Flowering Plants" lab, which is pages 19-34 in your Unit Packet.

Fast Plants:

Just water all of your plants, measure and record your measurements (of the stem) for each plant, and add GA to the plant leaves that call for it in the lab.

Flowering Plants:

In this 2-day lab, we basically just studied the anatomy of different monocot and dicot plants, while recognizing the differenced between the two types. It is necessary for you to know what the differences are between the stems, roots, and overall appearance (to the unaided eye as well as the aided eye) between monocots and dicots.

Here's a little review of key terms for this unit:

1. Xylem: Part of a plant's vascular system; the xylem conducts water and nutrients throughout the plant.
2. Phloem: Part of a plant's vascular system; the phloem conducts sugars throughout a plant's system.
3. Stomata: Slits on the underside of a leaf that allow for the exchange of gases (such as CO2 or water vapor).
4. Pith: The soft/spongy tissue in plants (serves as a kind of storage space for plants).
5. Angiosperm: A kind of plant that flowers and that has seeds enclosed in a carpel.
6. Root: The part of a plant that attaches itself to the ground to give the plant support and that absorbs nutrients and water.
7. Shoot: The part of the plant that consists of the stem, leaves, and the other parts of a plant (of which are typically above ground).
8. Leaf: A part of a plant that is typically green and blade like that is attached in some way to the shoot of a plant.

Homework for today:

• Work on UP p.19-34 (due 3/19)
• UP p. 41-54 (due 3/19)
• WILDLAND PROJECT (should finish by end of the week)
• Yellow CH28 study guide (Due 3/19)
• Read CH 29 (due 3/20)

Note: Unit Test is on 3/23--this week on Friday!!! STUDY :)

March 15, 2012

Today in class like most other days we first went and measured and watered our plants. Then after doing this, we worked on UP pages 19-34 which is the flowering plants lab for the rest of the class period.

Flowering Plants Lab

1. pages 19-21: these pages focus on the different parts of a plant including the stem, roots, leaves, and root and shoot system. Most of the answers to these questions can be found in the book and the notes that we took in class. And if someone did not get to see the roots of the plants in the classroom, they looked similar the the root system at the top of page 20
2. pages 21-22: these pages are review of the differences of monocots and dicots
3. page 23: this page focus on roots and many of the answers are in the notes packet and book
4. pages 24-27: these pages dealt with the cross sections of plant roots and stems and their specific parts. Remember, monocots and dicots have differences in their root and shoot cross sections which explains the difference in looks of the cross sections. Note: we did not do the celery stalk lab
5. buttercup root cross section -----monocot root cross section
6. pages 28-30: these are pages dealing with dicot woody stem plants and recognizing the different parts of them. Just saying, it is much easier to answer the questions if you read the information that is given beforehand.
7. pages 30-32: they deal with the parts of a leaf in general and there are many of the same terms that we saw earlier on in the lab.
8. Pages 33-34: these are review questions based on the lab and are a very good source of review.

Just as a reminder, remember to label all of images as the directions say to do and label and write the magnification of all of your drawings that you viewed in the microscope.

Homework:

work on UP 19-34

UP 41-54 -> due on monday

yellow chapter 28 study guide -> due on monday

wildland project

bring textbook

NEXT: Emma

March 13, 2012

Today We:

Measured our plants (if you missed today, get the data from your partner)

Took a quiz on Chapter 16

Completed Chapter 28 Notes

Watched a video on plants in the rainforest

Plant Growth (a bit of review):

Primary growth: lengthening

1. Cell division- mitosis at apical meristem region
2. Elongation- root gows longer
3. Maturation- root hairs develop

At the very end of the meristem ther is a root cap, which protects the area of the meristem going through rapid mitotic growth.

Secondary Growth: thickening

Vascular Cambium: Arranges vasdcular bundles and gives rise to secondary phloem and xylem.

Cork Cambium: Produces cork, which is dead when mature (aka bark) and protects the stem.

How Secondary growth works: To survive, the plant must produce xylem and phloem. Xylem is on the inside of the vascular cambium (closer to the center), and phloem is on the outside. This first set of xylem and phloem is primary xylem and primary phloem. When this vascular tissue becomes old, new tissue must replace it. The vascular cambium makes a second set of vascular tissue, or secondary xylem and secondary phloem, which is now the closest set of tissue to the vascular cambium. The alive, secondary tissue (produced second) pushes the primary xylem further in, and the primary phloem further out. The phloem pushing against the cork causes it to crack, resulting in rough bark.

Why shouldn't we peel bark off trees?: Then, you are ripping off a layer of phloem, the life source for the trees. Basically, you're a tree killer.

Pollinators (vectors) Have a Mutualistic Relationship with Flowers!

Flowers:

1. Pollenation- the chances of fertilization, and the formation of a seed, is greatly increased

2. Seed dispersal- seeds are taken away to colonize new environments with mre resources

Pollinators: They get food!

1. Bees are attracted by scent

2. Birds are attracted by red and pink petals

Homework: Work on the project, read UP 41-54

NEXT: VINISE

Chapter 16 Summary

March 12, 2012
Ch 16, plants, fungi, and the move onto land

Plants are extremely important to all living things on the Earth. It porvides numerous essential things needed for survival, like food for nearly all living things, it exchanges gasses for oxygen, which is needed for us to survive, paper, building materials, shelter clothes, things like rubber, and so on. unfortunately, plants are being wiped out more than ever before in their existence, all because of people. Plants are being killed faster than they can regrow, which could cause a mass extinction worse than any other.
the kingdom of plants are eukaryotic, multicelled, and use photosynthesis as a means of getting food/energy.

vocab
stomata: pores under leaf for gas exchange
cuticle: waxy layer on leaf that help the plant reduce water loss
Lignin: hardens cell wall
In vascular system
Xylem: transports water up stem/roots
Phloem: transports food
Yhe 4 major groups of plant evolution
Bryophytes: mosses
Ferns: vascular system
Gymnosperms (means "naked seed"): coniferous trees, first seed plants
angiosperms: flowering plants

Bryophytes have flagellated spores, and the only one whith gametophytes as the more primarily seen (over sporophytes)

Need damp places to fertilize because still dont have seeds and need to disperse

Moss doesn't have lignin

Ferns

12000 species, usually in tropics or temperate woodlands in the US.

first to have phloem and xylem

still no seed, sperm flagellated, so need damp environment

sporophytes dominant stage

Gymnosperms (naked seed)

have cone seeds, on dry land, can withstand harsh winters

thick cuticles and stomata, has lignin

sporophyte dominant, gametophytes are the cones

has pollen in male cones

wind carries pollen to female cones, not water

female cones contain eggs and ovaries

male cones are smaller, female cones higher on tree to help with the dispersion of seeds

Angiosperms

dominate almost any region on earth

250000 species

supply nearly all food and fibers

better vascular system, more efficient

has flower, caused to be one of the most sucessful types of organisms ever

flower have male (stemen: anther and filament) and female (pistol/carpel: stigma, style, ovary) parts on a flower

extremely diverse, doesn't have to rely on wind or water

has double fertilization: one sperm to egg, one to a polar body which then creates a endosperm that contains a large amount of nutrients used until the plant can photosynthesize

fruit are actually matured ovaries, they help protect and disperse the seeds

Next scribe: whoever kiran said