TSOTS Assignment #7: Anthers and Stigmas and Styles, Oh My!

How do flowering plants (angiosperms) like our Brassica oleracea plants reproduce? That is the basic question we will address with this lab and TSOTS assignment.

Begin by reading section 14.4 in the digital class textbook to get a basic introduction to flowering plants. Study the Figures 14.4.2, 14.4.3, and 14.4.4 very carefully to get a good idea of how flowering plants reproduce. Pay particular attention to Figure 14.4.3.

When you have finished your reading, get permission to visit the main garden where your TSOTS plants are growing and harvest two or three open flowers from your plants or those of another group. Bring these flowers back to the classroom and, with a partner, get a dissecting microscope. If you have never used a dissecting microscope before, read this brief tutorial on dissecting microscopes first.

Study Figure 14.4.2 carefully. Now, follow the procedure below to complete the flower dissection.

1. Lay your flowers on the table and take a closeup picture of one of them. In the next step, looking through the dissecting microscope, you will examine all of the flower's parts that are directly involved in reproduction.
2. Now, using forceps and/or your fingers, very carefully remove the sepals and petals of one of the flowers. Do you see the anthers?
3. This step can be tricky: take a picture of the image of the anthers coming out of the eyepiece of the microscope.
4. Now pull back the filaments and anthers to reveal the carpel (the entire female reproductive structure). Take a photograph of the carpel, focusing on the stigma.
5. Take the ovary and use very sharp scissors or your fingernails to cut the ovary open lengthwise. Do you see the ovules inside? They look a bit like shiny green jelly beans attached to a central stem. Take a picture of the ovules inside the ovary.
6. For extra points, take one of the anthers and tap some of its pollen onto a glass slide to prepare a wet mount slide of pollen. Ask the teacher for a compound light microscope and set it up on the lab station at which you are working. Get the pollen grains in focus at high power and try to capture a photo from the eyepiece of the microscope with your camera.

Using the photos you took to illustrate, write a paragraph explaining how fertilization occurs in flowering plant species like Brassica oleracea. Each picture you post should also include a detailed caption explaining what is shown in the photograph and how it functions in angiosperm reproduction.

Take a look at the example images below to get an idea of what you should capture in your photographs.

This image shows anthers surrounding a stigma. They are all part of the same flower. When both male and female parts appear in the same flower, the flower is said to be perfect. In some species of flowering plant, the male and female parts are located in separate flowers (some flowers are male, some are female), and yet another situation is when the male and female flowers are on entirely separate individuals (some plants are male, some are female).

Here is a view (40x) of the male reproductive anatomy of a flower, known as the stamen. It has a stalk called the filament coming up from the base of the flower and at the end of this stalk is a part called the anther. This portion of the stamen produces and releases pollen grains, which contain the plant's male gametes (sperm cells).

This is a view (40x) of the female anatomy of a flower called the carpel. The carpel consists of a stalk called a style with a sticky tip called a stigma. It is this sticky tip to which pollen grains adhere (get stuck).

This is a picture of a flower that has had all of the parts stripped away (sepals, petals, stamens, and the top of the carpel) EXCEPT the ovary (the large green tube on the right), which has been sliced open and has tiny ovules (immature, unfertilized seeds) spilling out--one of these ovules can be seen to the left of the ovary.

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TSOTS Assignment #6: How Does Your Garden Grow?

Now it's time to put some of your recently acquired science skills and knowledge into practice.

Your first step today should be to visit your plants in the garden. Try to find your group's plants. If you can't, don't worry--the most important thing to do is to notice the changes all of the plants have experienced. Snap a few pictures with your phone's (or other device's) camera and then return to the classroom. Briefly discuss your observations with your group and then proceed to answer the following questions in a post titled "How Does Your Garden Grow?".

1. How is your plant (or any plants in our garden, for that matter) getting bigger and adding biomass? Your explanation should correctly use the terms and concepts of cell division (mitosis), photosynthesis, and cellular respiration.
2. Phosphoglycerate kinase (PKG) and ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) are two important enzymes used in photosynthesis. Describe how plants in the garden would make enzymes like these if a signal was sent to the nucleus of a leaf mesophyll cell to produce more of one of these enzymes. (Hint: enzymes belong to which category of biomolecule?)

Be sure to talk with your group members and other classmates about the questions as you attempt to compose your responses--together you should be able to come up with some very thoughtful explanations.



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TSOTS Assignment #5: Seed Stories, Semester 1

Now it's time to sit back for a few moments and ruminate on what you have done and experienced so far this year through doing The Story of the Seed project. What have you learned? What surprised or amazed you? What made you laugh? What made you pause and think a little deeper? What was frustrating about this project? Take five minutes to talk about it with your teammates. Listen carefully to each person's reflections on what the project has been like for him or her. What questions do you have about things you observed or experienced in the garden? OK, now, guess what? You are going to write about the experiences of one of your classmates--someone who was not on your team! Find someone from another group and work closely with that other person to summarize his/her answers to the questions above in a short paragraph that you will post under your name. Your post title should include that other person's name (e.g., "John's Seed Story"). Happy interviewing!



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TSOTS Assignment #4: An Ecological Analysis of the Garden and your Plants

Now that you have read about and discussed some of the factors that influence the forms and behaviors of ecosystems, apply those ideas to the appearance and behaviors of the garden in which your Brassica oleracea plants are growing by developing an analysis guided by the following questions:

1. What are some abiotic factors on which your plant depends for its survival? What about biotic factors that affect your plant? Describe some of these factors.
2. How do you know your plants are engaged in competition? For what are your plants competing, and who is the competition?
3. How are "winners" and "losers" determined in this struggle? Is it always so clear cut who "wins" and who "loses?" What makes that determination complicated sometimes?
4. Describe other types of interaction (besides competition) in which your plants are involved. Make sure to explain how this interaction affects each organism involved.
5. What evidence is there in the garden that succession (or something like it) is occurring in the garden ecosystem? Does it seem more like primary or secondary succession?

It is advisable to address each set of questions in a separate paragraph. This will improve readability of your analysis.



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TSOTS Assignment #3: Biogeochemical Cycles and Your Plants

Now that you have some idea of how the many parts of an ecosystem are interwoven and interact to keep life going, consider and respond to the following questions:

1. What changes do you notice in your plants this week? Describe the overall appearance of your plant.
2. How do your plants participate in the movement of water in the biosphere? How do your plants' roles in the water cycle relate to the changes you observed in your plants this week?
3. How do your plants participate in the movement of carbon in the biosphere?  How do your plants' roles in the carbon cycle relate to the changes you observed in your plants this week?
4. How do your plants participate in the movement of nitrogen in the biosphere?  How do your plants' roles in the nitrogen cycle relate to the changes you observed in your plants this week?

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TSOTS Assignment #2: Project Description

Instructions for  TSOTS Assignment #2:

1. Compose one paragraph (4 to 5 sentences) in which you explain what you think The Story of the Seed project is all about and what you think you might learn by doing it. This paragraph should go in a section just below your "My Bio" assignment.
2. When you are ready, hit "Publish" to make your changes live on your biology portfolio website. 

If you are having trouble coming up with a description of this project, see my "About" page.

This Student Blog Post Assignment should be completed within one week of it being assigned.

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TSOTS Assignment #1: My Bio

 Before you do anything else with your individual biology website today, make sure you verify that it was set up correctly per Mr. Bursch's instructions and example student site. If there are any issues you must resolve those FIRST.

Once you have have verified that your site was set up correctly, you will complete your first official assignment for The Story of the Seed project--yes, that means this one is for points! By Monday, you'll need to publish a simple bio about yourself on your The Story of the Seed page of your individual biology website. In your post, please include responses to the following questions:

- What is your name? In what places have you lived (city and state is enough)?
- Have you ever gardened or grown food before? What did you grow and what do you remember about the experience?
- Talk about a person or people in your life who you think know a lot about gardening, farming, horticulture, plants, and/or making food from scratch. Who is this person? What is their relationship to you?


EXAMPLE I

My name is Joe Green. I am originally from Waukesha, Wisconsin. I moved here in 2002 with my mom and older sister. My Grandparents still live in Wisconsin and sometimes we get to go back and visit them in the summer.

I haven't really gardened that much, but sometimes I help my mom with her rose plants. I don't really cook that much, but I like to watch my sister cook and ask her about the ingredients she puts in the food she is making. She's a pretty good cook, but not as good as my grandma. My grandma and grandpa have a huge garden back in Wisconsin and my grandma makes pickles from the cucumbers she grows in the summer. They're tasty, but my favorite thing is pickled watermelon. I know it sounds gross, but it is so good! Whenever we go back I always spend some time helping my grandpa out in the garden. I don't really know what all of the plants are or how he gets them to grow so big, but it's cool to learn about them. Maybe after this project is over I will know a little more about some of these plants like kohlrabi.

EXAMPLE II 

I'm Marisol Martinez and I am from Salinas, CA. My grandmother, my dad, and his brother moved to San Jose in 2007. I have family in Salinas, Watsonville, Hollister and Mexico.

I cook many of the meals at home so I know how to cook. I learned most of what I know from my grandmother. She grew up in Tamaulipas, Mexico. My favorite thing to make that I learned from her is mole de olla con lentejas. I don't know exactly how to say it in English, but one of the ingredients is little seeds that kind of look like tiny beans. My grandmother probably knows the most about food and cooking of all of my closest relatives. I like coliflor, but my group is growing brussel sprouts. I like gardening. In my third grade class we had a garden and I planted carrots and we got to eat them at the end of the year. They were really sweet and very orange in the middle.

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