Botanical Explorations with the Dissecting Scopes
Plant Cells and Scientific Drawings |
We located these samples on the Armstrong campus (outside of the Science Center and near the mailroom). We chose these samples because of the color of the Copper Canyon Daisy, and texture of the Muhly Grass. The Copper Canyon Daisy is a beautiful yellow orange color and the Muhly Grass has a wispy, furry texture. We obtained the samples and observed them under a dissecting scope. We noticed the color and shape of the stigma of the Copper Canyon Daisy which was yellow and curled outward and resembled a fallopian tube. We also noticed that the stem of the Muhly grass had tiny black dots and there were bulbs on some of the florets.
- Kourtnei & Nooriya |
For today's lab our objectives were:
We isolated samples of the following plants. We learned different staining techniques for different specimens, the visual difference between a chloroplast and chromoplast, we were able to see the differences in starch between a ripe and unripe banana, that the vacuole in the epidermal cell of the onion was the reason for the nucleus being pressed up against the cell wall.
-Kourtnei and Nooriya
- prepare a wet mount slide for viewing under a compound microscope
- recognize the different slide preparations techniques of: whole mount, epidermal peel, sections (cross and longitudinal) and smears
- Find and identify visible features of the plant cell (cell wall, vacuole, nucleus, chloroplasts, cytoplasm etc.)
- Using biological stains to make features of plant cells visible for microscopic study
- Produce a scientific diagram
We isolated samples of the following plants. We learned different staining techniques for different specimens, the visual difference between a chloroplast and chromoplast, we were able to see the differences in starch between a ripe and unripe banana, that the vacuole in the epidermal cell of the onion was the reason for the nucleus being pressed up against the cell wall.
-Kourtnei and Nooriya
Photosynthesis
Objectives for this lab:
This week in lab, we used chromatography to extract pigments from a Magnolia leaf and then used a spectrometer to measure the light absorption of each pigment. We used phenol red to observe carbon dioxide consumption in photosynthesis by adding Elodea to 2 test tubes containing phenol red with carbon dioxide (introduced from our own breath via straw). We then placed one test tube in the light and one in the dark along with controls (which did not contain the Elodea). We tested starch using leaves from the coleus plant. We removed the anthocyanin by dipping it in boiling water, then we removed the chlorophyll by dipping the same leaf in boiling ethanol. After this we added iodine and observed the staining pattern.
"My favorite part of this lab was using the spectrometer because I enjoyed working with scientific equipment and learning how to effectively use it to obtain results for an experiment." - Nooriya
We learned how to extract pigments using chromatography and how to use a spectrometer. We also learned that phenol red turns yellow when it is acidic, but orange when some carbon dioxide is introduced (too much carbon dioxide reacts to form carbonic acid which turns the phenol red solution yellow). We learned that more starch is present in leaves that are in the light than the dark.
- Kourtnei & Nooriya
- Use chromatography to separate and identify various pigments found in photosynthetic plant tissues.
- Explain why it would enhance a plant's success to have more than one type of photosynthetic pigment.
- Demonstrate that carbon fixation during the "synthesis" reactions of photosynthesis is dependent on products of the light-dependent reactions (that is, not carbon will be synthesized in carbohydrates unless the light-dependent reactions are taking place simultaneously).
- Use a starch test to examine the effects that carbon-starvation and light-deprivation have on the synthesis reactions of photosynthesis.
This week in lab, we used chromatography to extract pigments from a Magnolia leaf and then used a spectrometer to measure the light absorption of each pigment. We used phenol red to observe carbon dioxide consumption in photosynthesis by adding Elodea to 2 test tubes containing phenol red with carbon dioxide (introduced from our own breath via straw). We then placed one test tube in the light and one in the dark along with controls (which did not contain the Elodea). We tested starch using leaves from the coleus plant. We removed the anthocyanin by dipping it in boiling water, then we removed the chlorophyll by dipping the same leaf in boiling ethanol. After this we added iodine and observed the staining pattern.
"My favorite part of this lab was using the spectrometer because I enjoyed working with scientific equipment and learning how to effectively use it to obtain results for an experiment." - Nooriya
We learned how to extract pigments using chromatography and how to use a spectrometer. We also learned that phenol red turns yellow when it is acidic, but orange when some carbon dioxide is introduced (too much carbon dioxide reacts to form carbonic acid which turns the phenol red solution yellow). We learned that more starch is present in leaves that are in the light than the dark.
- Kourtnei & Nooriya
Simple & Complex Tissues
Objectives:
1. Compare and contrast parenchyma, collenchyma, and sclerenchyma cells and tissues (ground tissue system).
2. Recognize the three tissue systems of the plant body.
3. Identify water-conducting cells of the vascular tissue system and relate their structural features with their functions.
4. Describes the characteristics of the epidermis.
In this week's lab we collected and observed simple and complex tissue samples from plants. We learned how to correctly collect and stain tissue samples and how to identify parenchymal, collenchymal, and sclerenchymal tissues. We also learned how to identify complex tissues such as xylem, phloem and epidermal tissue.
1. Compare and contrast parenchyma, collenchyma, and sclerenchyma cells and tissues (ground tissue system).
2. Recognize the three tissue systems of the plant body.
3. Identify water-conducting cells of the vascular tissue system and relate their structural features with their functions.
4. Describes the characteristics of the epidermis.
In this week's lab we collected and observed simple and complex tissue samples from plants. We learned how to correctly collect and stain tissue samples and how to identify parenchymal, collenchymal, and sclerenchymal tissues. We also learned how to identify complex tissues such as xylem, phloem and epidermal tissue.
GMO Investigation
The objectives for this lab are:
-Kourtnei &Nooriya
- explain what a genetically modified organism is.
- describe the process of extracting DNA from store-bought food products.
- describe how polymerase chain reaction amplifies target DNA sequences
- discuss some of the implications for genetic engineering of agricultural crops, both positive and negative, in regards to plant biodiversity, ecosystems, co-evolution of plants and their pests, human health, and economics.
-Kourtnei &Nooriya
The food that we tested today was a Kashi Chocolate Almond and Sea Salt with chia seeds granola bar. The ingredients of this granola bar are: Rolled Whole Grain Blend (Hard Red Wheat, Oats, Rye, Triticale, Barley), Brown Rice Syrup, Roasted Almonds, Soy Protein Isolate, Semisweet Chocolate Chunks (Organic Cane Syrup, Chocolate Liquor, Cocoa Butter, Soy Lecithin, Ground Vanilla Beans), Invert Cane Syrup, Defatted Soy Grits, Dried Cane Syrup, Chocolate Liquor, Chicory Root Fiber, Chia Seeds, Degermed Yellow Corn Flour, Honey, Expeller Pressed Canola And Safflower Oil, Rice Starch, Cocoa, Vegetable Glycerin, Sea Salt, Oat Fiber, Nonfat Milk, Kashi Seven Whole Grains & Sesame Flour (Whole: Oats, Hard Red Wheat, Rye, Brown Rice, Triticale, Barley, Buckwheat, Sesame Seed), Natural Flavors, Soy Lecithin, Peanut Flour, Mixed Tocopherols For Freshness. We hypothesize that this will test negative for GMO because we learned in class that wheat has not been approved for GMO to be added and one of the main ingredients in our test food is wheat.
Preparation of PCR tubes.
Tubes 1,3,5 all have the green master mix which determine if you have extracted plant DNA or not. The green master mix is a way to identify the DNA sequences that are common to most photosynthetic plants using primers that specifically amplify a section of the chloroplast gene used in the light reaction, which are green.
Preparation of PCR tubes.
Bottom of Tubes 1,3,5 all have the green master mix which determine if you have extracted plant DNA or not. The green master mix is a way to identify the DNA sequences that are common to most photosynthetic plants using primers that specifically amplify a section of the chloroplast gene used in the light reaction, which are green.
Our test tubes in the thermocycler. The thermocycler, or PCR machine, carries out the 40 cycle reaction of PCR. Each cycle consists of a denaturing step, annealing step, and extending step. First it will denature the DNA template by heating it to 94°C. Then the temperature will be cooled to 59°C so the primers can anneal to the DNA. Finally, the temperature will be increased to 72°C, which is the optimal temperature for DNA polymerase functionality.
Next week we will use gel electrophoresis to visualize the products of the polymerase chain reaction and will obtain the results of this experiment.
GMO Investigation Part Two: Gel Electrophoresis
The goals for this lab were to:
-Kourtnei & Nooriya
- explain the process of electrophoresis
- interpret the results of gel electrophoresis of your PCR samples from last week
- describe how both positive and negative controls were necessary in order to assess the validity of our results for this investigation
- discuss some of the implications for genetic engineering of agricultural crops, both positive and negative, in regards to plant biodiversity, ecosystems, co-evolution of both plants and their pests, human health and economics.
-Kourtnei & Nooriya
Picture of our gel for gel electrophoresis.
Gel electrophoresis is a way to separate mixtures by size. The way gel electrophoresis works is that the molecules we are trying to separate are getting pushed through an electric field through a gel that contains small pores. These will show up as bands, which will be different sizes based on the type of molecule. The type of stain we are using to view our molecules is called SafeView.
The first lane (1) was non GMO w/ plant primer and that showed a band. The second lane (2) had our negative control to test for contamination had no band so there was no contamination. Our test foods (3&4) showed inconclusive results for our test foods. The next two lanes (5&6) had our GMO positive controls and they both had a band so that ensured the PCR worked. Lane 7 had our MWR so we could measure how big the bands were.
Results of our gel:
Questions about our GMO Investigation:
Questions about our GMO Investigation:
- What was your test food? Kashi Bar
- Did your test food generate a 200 bp band with GMO primer (lane 4)? No
- What does this tell you about the GMO status of your food? Our results were inconclusive.
- What other information do you need to confirm the GMO status of your sample? That is, how do the results of your other five PCR samples help support or undermine your result for your test food? The other five PCR samples proved that our experiment did work, we just didn't extract any DNA from our test food.
- If you were to repeat the procedure, what laboratory practice might yield better results? We would use a lot more sample to try and actually get some DNA extracted as well as try and pipette better to try and reduce human error.
Bryophytes and Ferns
Lab Objectives:
1. Recognize representatives of the Phylum Bryophyta and the Phylum Hepaticophyta (non-vascular) plants.
2. Recognize representatives of the seed-free vascular plants-the Monilophytes (also known as ferns) both as the microscopic and macroscopic level.
3. Use the nomenclature, both scientific and common, associated with each nonvascular taxon observed.
4. Describe the sequence of events that occur during the life cycles of each taxon observed and recognize the gametophyte and sporophyte generations.
5. Describe the general characteristics of the nonvascular taxa observed, and how those characters are used in their classification.
We prepared slides and observed different structures that are characteristic of Bryophytes. We did the same for ferns. We observed them at different stages in their life cycles both microscopically and macroscopically.
We learned about the structural changes that occur in the life cycle of Bryophytes and ferns, as well as the characteristics that distinguish them.
- Kourtnei & Nooriya
1. Recognize representatives of the Phylum Bryophyta and the Phylum Hepaticophyta (non-vascular) plants.
2. Recognize representatives of the seed-free vascular plants-the Monilophytes (also known as ferns) both as the microscopic and macroscopic level.
3. Use the nomenclature, both scientific and common, associated with each nonvascular taxon observed.
4. Describe the sequence of events that occur during the life cycles of each taxon observed and recognize the gametophyte and sporophyte generations.
5. Describe the general characteristics of the nonvascular taxa observed, and how those characters are used in their classification.
We prepared slides and observed different structures that are characteristic of Bryophytes. We did the same for ferns. We observed them at different stages in their life cycles both microscopically and macroscopically.
We learned about the structural changes that occur in the life cycle of Bryophytes and ferns, as well as the characteristics that distinguish them.
- Kourtnei & Nooriya
Whole mount of Sphagnum sp. (peat moss) gametophyte. The left is unstained. you can see the green chloroplasts towards the bottom and the empty looking hyaline cells. In the image on the right, the specimen has been stained with Phenol-Red to detect lignin, however lignin is absent in this group, therefore there is no red color. This was my favorite specimen because of how clearly I could see the hyaline cells. Viewed under 400x magnification. Image by Nooriya.
AngioSperms and GymnoSperms
The objectives for this lab:
1. Recognize representatives of the gymnosperms and angiosperms.
2. Describe the sequence of events that occur during the life cycles of each taxon observed and recognize the gametophyte and sporophyte generations.
3. Identify the parts of a flower and describe their functions.
4. Understand the terms related to ovary position, presence and absence of floral organs, and floral symmetry-and be able to use them to describe a specimen.
5. Prepare diagrams to record important features revealed during a floral dissection.
We learned the structures of a flower, and their functions. We also observed Cycads, Ginkgos and Conifers around campus and their distinguishing characteristics.
- Kourtnei & Nooriya
1. Recognize representatives of the gymnosperms and angiosperms.
2. Describe the sequence of events that occur during the life cycles of each taxon observed and recognize the gametophyte and sporophyte generations.
3. Identify the parts of a flower and describe their functions.
4. Understand the terms related to ovary position, presence and absence of floral organs, and floral symmetry-and be able to use them to describe a specimen.
5. Prepare diagrams to record important features revealed during a floral dissection.
We learned the structures of a flower, and their functions. We also observed Cycads, Ginkgos and Conifers around campus and their distinguishing characteristics.
- Kourtnei & Nooriya
Dioon edule is a member of cycadophyta. Cycads are the only gymnosperms with compound leaves and appeared 300 million years ago. They were dominant vegetation at that time. Cycads have roots that stick out of the grown that contain nitrogen fixing cyanobacteria. Cycads have flagellated sperm and are insect pollinated. Photo taken by Nooriya.
The photo on the top left is of the flower with the sepals removed. The top right is with the sepals and petals removed. The bottom photo shows the carpel and two styles, with stigma at their tips. This flower is zygomorphic and complete. It is perfect and has an inferior ovary. This was my favorite specimen because I enjoyed dissecting the flower. Photos taken by Nooriya.
Roots & C-Fern Observations (& Shoot Cuttings)
how identfyThe goals for this lab are to:
-identify external features of plant roots, including root hairs
-identify internal anatomy of plant roots
-distinguish monocot roots from those of dicots, both from external morphology and from internal anatomy
-describe the principle functions of roots
We learned how to identify external features of the dicot (pea) and monocot (corn). We also learned to identify root hairs and root caps. We learned how to do mitotic squashes and learned how to shoot cut as well as learned the functions of roots.
-Kourtnei and Nooriya
-identify external features of plant roots, including root hairs
-identify internal anatomy of plant roots
-distinguish monocot roots from those of dicots, both from external morphology and from internal anatomy
-describe the principle functions of roots
We learned how to identify external features of the dicot (pea) and monocot (corn). We also learned to identify root hairs and root caps. We learned how to do mitotic squashes and learned how to shoot cut as well as learned the functions of roots.
-Kourtnei and Nooriya