sci115 week 3 discussion and response

• “Phytoplankton, Chemosynthesis, and Mitochondria”

In this week’s discussion you will be exploring energy and how it’s captured, released, and used by all living creatures. For your primary post, respond to one of the following three topics and address all of the questions. Also, please reply to at least one fellow student on any topic.

Topic 1 : The phytoplankton that brought Earth to life. Review the video (1)* about the “phytoplankton that brought Earth to life” from the link given below. In this clip, Penny Chisholm discusses a tiny phytoplankton called Prochlorococcus. Based on that video, address the following:

• (a) What is the importance of Prochlorococcus for life on the planet Earth today?
• (b) In the video, Dr. Chisholm tells us that Prochlorococcus samples from different environments that are genetically different. What does this tell us about the relationship between organisms and their environments?
• (c) Share how this relates to this week’s lessons.

Topic 2 [article]: Snails that don’t eat. A recent article by JoAnna Klein (2)* describes a partnership between the snail Gigantopelta chessoia and a chemosynthetic bacterium. The bacterium is called an “endosymbiont” because it lives inside the snail.

• (a) Describe the partnership between Gigantopelta chessoia and its endosymbiont.
• (b) What is most surprising to you about this situation?
• (c) Explain how this relates to this week’s lessons.

Topic 3 [article]: Exercise and mitochondria. Exercise is generally known to have many beneficial effects on our bodies at several different levels. Some studies have examined the effects of exercise at the level of muscle cells. Read the press release by Cell Press (3)*.

• (a) What specifically did these researchers measure in their volunteers?
• (b) What were their findings?
• (c) Explain how this relates to this week’s lessons.

References (in Strayer Writing Standards format).

1. PBS Newshour, March 5, 2014. The phytoplankton that brought Earth to life, https://youtu.be/m_43nR11PW8
2. JoAnna Klein, July 11, 2018. This snail goes through metamorphosis. Then it never has to eat again. https://www.nytimes.com/2018/07/11/science/snail-metamorphosis.html
3. Cell Press, March 7, 2017. How exercise — interval training in particular — helps your mitochondria stave off old age.https://www.sciencedaily.com/releases/2017/03/170307155214.htm

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Good Afternoon Professor Sherif and classmates,

Snails that don’t eat.

(a) Describe the partnership between Gigantopelta chessoia and its endosymbiont.

There is a symbiotic bacterium in Gigantopelta chessoia and also an engorged esophageal gland.

Gigantopelta chessoia is a newly discovered species in genus Gigantopelta. Therefore, its

endosymbiont is the manifestation of endosymbiont bacteria that exist in the esophageal gland.

(b) What is most surprising to you about this situation?

I am surprised that the digestive system of snail stops to grow when it reaches a particular body

length.

(c) Explain how this relates to this week’s lessons.

The information presented in the article related to this week’s lessons because the

metamorphosis in which the snail goes through is similar to other living organisms. For instance,

shallow water corals can survive in water even though there is no sun.