Blog Post #10: Anthers and Stigmas and Styles, Oh My!

This week I dissected a flower in my biology class. During the dissection I got to observe the different parts of the flower up close. I got to see the male’s parts called the anthers and the female’s parts called the stigma, style and ovaries. The pictures shown below are some of the parts I got to observe under the microscope.

This is the carpel. The mushroom like head is called the stigma and its shaft is the style.

This image shows the anther, the male part of the flower where the pollen grains are produced.

This is the ovary where the fertile female cells are held. the capsules or ovules hold these female cells.

Now that you have seen what the plant’s parts look like, here is how they work. First off, flowers are angiosperms, which means that they reproduce within themselves. Every flower has both the male and female parts required to reproduce.The male part of the plant(Stamen) creates pollen which contains the plant's sperm cells. The pollen will eventually find its way onto the female part(Carpel) of the same or different plant species. The pollen can be distributed by insects such as as bees or by wind and animals. When the pollen is transferred to the stigma of another plant, the ovules will be fertilized inside the plant’s ovaries.

Post 10 Anthers and Stigmas and Styles, Oh my!

  

Raw un-cut broccoli flower.

              Side view of the ,anthers ,stigma ,style ,and stamen.
                                                  

This is the ovary which contain seed like ovules.

                                           

The carpel is located below.

   The production of a new plant is fascinating, but to realize the complexity, a understanding of the functions and cycles of these parts are necessary. They consist of as listed;Released from the stamen, Tiny pollen particles make a cross country journey on pollinators such as bees, and bats to reach another plants stigma.Once the pollen particles reach the stigma, they slide down the style and make their way into the ovary. The pollen then fertilizes four haploid cells and creates a combined ovum.Depending on the plant this may result in spores or seeds.

Blog Post #10, Anthers and stigmas and styles, Oh My!

 
Anthers and stigmas and styles, oh my!

This is a picture of the plant before we started to dissecting it for 

for scientific reasons.

 

This is a picture of a group of Anthers surrounding the stigma.The anther is connected to the Filament and together they make up the stamen. The Stigma is connected to the style  which is connected to the ovary.  They are all part of a prefect flower because the flower has both female and male parts.

 

This picture of the carpel the top is the Stigma, in the middle is the style than the ovary. This flower has more than one ovule. In the ovule is where female gametes are produced.

The stigma at the top of the Carpel, and is sticky. The stigma is where pollen grain frequently lands. Some flowers have several Carpel mixed together to from a single reproduction structure known as a compound Carpel.

Fertilization/Meiosis

First a pollen grain has to land near an Ovule. The grain will than split and grow a pollen tube with two haploid sperm nuclei. When the Pollen tube reaches the female gametophyte one sperm fertilizes the egg. Then fertilization produces a diploid Zygote (new plant). The Zygote turns into an embryo, then it will encase into a seed. The seed has three generation of the life cycle. The seed has three generation of the life cycle. The Seed Coat is part of the older generation, the haploid cell in the embryo is part of the female gametophyte, and the embryo in the new plant.

Blog Post #10 Anthers and Stigmas and Styles, Oh My!

As I examined broccoli flowers from the Brassica Oleracea, I noticed that the ovary is located at the base of the stigma, surrounded by the sepal. As a whole, the female reproductive system is called carpel. For the male reproductive system, pollen is stored at the top of the anther. When the stamen releases the pollen grains on the anther, each individual pollen grain produces four haploid spore cells and the walls of the pollen grain strengthen to prevent dryness until it sticks to the stigma of another plant. The pollen is then taken down the style and into the ovary, where every ovule produces four haploid cells that cohere with the four haploid cells of the pollen grains. A zygote is then formed  which will then be deposited into the soil to spring up a new sporophyte plant! Here are some pictures below to help you better understand what these complex reproductive organs look like.

Here is a photo of the whole broccoli flower, with the reproductive parts inside.

 This photo clearly highlights the male anthers on the stamen, and the stigma which is connected to the style.

Only the carpel is shown here connecting the style above.

These are the single ovules found inside the ovary.

The pollen grains are shown here, where the male haploid cells are located.

A Matter of Selection

Over time, the brassica oreala family has evolved into different variations of the plant. The plants have developed different colors, sizes, and leaf shape. In Willow Glen’s garden I have observed the plants and their differences. The greatest characteristic variation between each of the plants were the shapes of their leaves. The greatest range of variation was shown in the plant and stem color.

Siberian Kale:

• Dark green leaves
• Ruffled edges
• Purple stems

Cabbage:

• Green leaves
• Light green stem
• Wide leaves

Dino Kale:

• Bumpy texture
• Skinny leaves
• Dark dark green leaves
• Light green stem

Purple Cabbage:

• Smaller size
• Dark purple leaves
• Purple stem

Kohlrabi:

• Dark green leaves
• Purple stems

Broccoli:

• Tall
• Green stem

These many variations were over a long period of time. During this long period the plants genes changed to suite the environment. Artificial selection might have also been apart of the change in the plants. Humans would alter the genes to produce a better outcome. This is a form of selective breeding because humans are breeding the plants for particular traits. This type of change is not always the case. Some plants evolve through descent with modification. This event occurs when a plant is forced to adapt to a change in the environment and one specific trait becomes more dominant to better suite the change. These shifts in the plants genes cause natural variations in offspring over time. Mutations are also a large reason why the plant has changed so much over time.

The most consistent part of the anatomy in the brassica olercea family were the colors of the plants leaves and stems. Each of the leaves were a certain shade of green. For instance the cabbage, cauliflower, and dino kahle all had a shade of green leaves and green stems. I believe the reason why this trait never seemed to change is because there was never a need to or a change in the environment that forced them to change their color.

In order for a breeder to obtain a specific trait they would have to use different methods. For instance, the method most commonly used today is done by extracting a specific trait from a plant and embedding it into another. Another  more natural way would be putting the plant into a different environment causing it to adapt and change over time.

Blog post #9 -- A matter of selection

              The size and shape of the leaves in the brassica oleracea family show the most variation. The two most polar opposite plants in this family would be kale and cauliflower. The Kale's leaves are thin and have ridges every so often while the cauliflower exhibits wide leaves that curve at the edges. Their length is about the same ranging from 22 cm to 24 cm, but the cauliflower's leaves are much wider. they measure each about 20 cm wide while the kale is only 11 or 10 cm wide.
            I believe that this is due to selective breeding and mutations. Because the plants were always in the same geographic area, descent with modification would be harder to encounter. The decrease in bees has definitely caused some changes in which species have bred more. This selective breeding lead to mutations in the wild cabbage that later created many different variations.
          Most of the b. oleracea that has blossomed looks the same. For example, the kohlrabi and cauliflower both had tall, yellow blossoms. Not many of the plants were in their full adult form yet so I could not tell which of them would show the same flowerings. The blossoms were close together in both cases and almost identical to other Kohlrabi organisms.
         For plant breeders to get desired characteristics into plants, they must selectively breed two plants with the traits they choose. If a botanist were to want another gene in their gene pool, they would have to introduce a separate brassica oleracea plant who can breed with a different blossoming.

             

Blog Post #9

The evolution of Brassica Oleracea is a fascinating and amazing process. Because of selective breeding there are many types of Brassica Oleracea. The part that exhibited the most variation is the leaf, and the two types of Brassica Oleracea that are almost opposites are Siberian kale and the Purple Cabbage. The Purple Cabbage has big, long,and purplish kind of leaves. While the Siberian kale have long, rough texture, tattered edges, and greenish type of  leaves. The Siberian kale is 29 cm long, and 11 cm wide. The Purple Cabbage  is 20 cm long and 15 cm wide.Both plants have purple stems.

The Brassica Olercea plants come in many forms. Because of artificial selection and changes in their genes. Because the brassica oleracea changed genes they were more adapted, because humans started to selectively breed them. They were selectively bread to meet peoples expectations. Although humans have caused most of the brassica oleracea to be so diverse descent with modification  also  plays a role in this. If some unusual thing occurs the plants with a trait that helps it in that situation will become dominate.There is also natural variation witch selects traits for or against something and mutation are other reasons why plants are so diverse.

The stem of the plants were the most consistent because they were all about the same size about 1 cm. One of the reasons that the stem  is so consistent is because the stem is one of two main structural axes of a plant. The only difference is the color. Some are yellow green, purple, or white.

 For plant breeders to get the stem to become much different they have to find certain traits in other plants and breed them together or transfer it in some other way. This is called selective breeding. The brassica oleracea plants would never be this diverse if it was not for selective breeding. 

Blog post Number Nine (A matter of selection)

       After measuring a variety of plants I believe that the most variations are expressed through the sizes of leafs as shown in the pictures below.

29cm

                                                                             22cm

19cm

15cm

35cm

                                                                Leaf lengths

                                                                      Leaf lengths

So much variability in the domestic brassica oleracea traits is a cause of selective breeding by humans, also known as artificial selection. Selective breeding alters an organisms genes over time which never inevitably changes the organisms appearance. Some differences might also be the cause of mutations (natural variations) which are random changes that occur in an organisms genes. The last possibility is descent with modification which is the inheritance of traits from parent organisms but with mutations in its genes.

                   The main similarity in all the plants that I noticed was the stem structure. As you can see in the picture above, they have a semi rectangular structure with occasional digits coming off of the side of the plant. The rectangular structure applies a great deal of  support throughout   the whole plant allowing it to grow bigger without collapsing. For data what I have are the images this is a vital observation.

                    To acquire more in genetic variation, Plant breeders we need to take the few plans with different stems and breed them with the rectangular stemmed plants. This is also known as selective breeding.

Mason's GATTACA Essay

G.M.H

The future holds many untold wonders and possibilities in a vast number of scientific branches, especially genetics. There may be ways to genetically enhance the probability of desirable traits in future generations. Genetically modifying human beings can have both positive and negative effects.

On the positive side, genetically modified humans (GMH) could be engineered to have just about any given trait. This means that we can adapt faster than any other species.Humans could be built for the future. A possible scenario could be a high chance of solar flares, And people with dark skin would have less of a chance of getting skin cancer. So instead of not adapting quickly enough, doctors could advise soon to be parents to choose a dark complexion for their children. One generation would be all that it takes to adapt.

For our current time it seems ethically wrong to select which embryo survives and which one dies. Basically, we are illuminating natural selection, and beginning abortions at an even earlier stage in life. Depending on how our citizens opinions last throughout the years this might not even be an option. It is still uncertain that embryos can feel and think.

There isn't only ethical issues, but biological issues two. If humans need to reproduce naturally, our bodies might become unable to support life without electronics. This means that if some sort of un-calculated disaster strikes, humans slowly die off, or every time a person is pregnant there would be a great chance that the mother would die before or after the baby is born.

The negative effect seemed to outweigh the positive effects for now, but given that we are faced by a future disaster many of the ethics ideas would be dropped. When someone is desperate sense is to be thrown in the recycle bin and used for later.

Gattaca essay

Many modern  foods are filled with GMOs or genetically modified organisms. When foods have GMOs in them, they predispose consumers to diseases such as diabetes, or even cancer. Foods such as Reese’s® are known to carry GMOs, and they have been shown in movies such as Food Inc. or Gattaca. Genetically modified organisms should be banned because they are not healthy, or contribute at all to humans.

GMOs do not only carry negative affects to the population though. Using GMOs on plants has proven to make them taller, wider, and feed more. The products with these GMOs are priced lower in stores so that customers are persuaded to buy foods that are not organic. But even though they are priced lower, you have already paid a portion of taxes to these big scale farmers for GMO infused foods. Families stricken with poverty have no choice but to buy these non-organic products because they cost less. Families such as these either have to buy these products that seem healthy or buy fast food, which gives these big companies the upper hand.

So far, genetically modified organisms have not contributed anything but a bigger risk of autoimmune attacks but, harm can still come if we cease to continue in their growing. Because prices will have risen, poor families will have no choice but to resort to fast food. This will cause unhealthy diets and eventually lead to obesity. Farmers will also have a hard time gaining money because corporates won’t pick them up for using, or not using GMOs.

On the bright side, discontinuing GMOs will ultimately give us better lifestyles. Ending the life of genetically modified organisms will also end the raigne of cancer caused by GMOs, nitrates, and other unhealthy substances added to foods. Although poorer people may not be rich enough to afford all foods, they will also be more accustomed to healthy lives.

Genetically modified organisms have been an issue for the past decade, and years before. They pose a serious threat and if we overlook them, we will pay our health. If we end the usage of genetically modified organisms, we will be overall better off than we would be with them.  In conclusion, we should get rid of  genetically modified organisms and everything like them.