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astronomy

Ivan Wallin

Ivan Wallin is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Ivan Wallin rather than just read about it. In short: Ivan Emanuel Wallin (22 January 1883 – 6 March 1969) was an American biologist who made the first experimental works on endosymbiotic theory. Nicknamed the "Mitochondria Man", he claimed that mitochondria, which are cell organelles, were once independent bacteria, as supported by his comparative studies and culture of isolated mitochondria.

Key takeaways

  • Ivan Wallin belongs to astronomy; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Ivan Wallin to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Ivan Wallin from memory before moving on to harder problems.

Reference excerpt

Ivan Emanuel Wallin (22 January 1883 – 6 March 1969) was an American biologist who made the first experimental works on endosymbiotic theory. Nicknamed the "Mitochondria Man", he claimed that mitochondria, which are cell organelles, were once independent bacteria, as supported by his comparative studies and culture of isolated mitochondria. From 1922, he published a series of papers titled "On the nature of mitochondria" in the American Journal of Anatomy which became the experimental foundations of his claims. He was the first person to specifically postulate that eukaryotic organelles originated from bacteria, and that symbiosis is a major force in creation of new species. Wallin was Professor of Anatomy at the University of Colorado School of Medicine. He was noted for his eccentric life in academia, such as his preference for exclusively practical demonstration rather than lecturing, his frequent parties for students and an annual Christmas glögg party.

Biography Wallin was born to Swedish immigrant parents, Claus Henrik Wallin and Emma Augusta Maria (Johansdotter), in a small farming community at Stanton, Iowa. He was educated at Augustana College at Illinois and Princeton University. He obtained a BS degree from the University of Iowa in 1905. He briefly taught biology at the University of Nebraska from where he earned his MSc in 1908. In 1915 he obtained his doctorate degree (DSc) in anatomy from the New York University. His thesis was on the tissue development, differentiation, and morphology of the lamprey Ammocoete. From 1918, he was professor of anatomy at the University of Colorado School of Medicine.

Origin of mitochondria Wallin was the first to experimentally investigate the origin of mitochondria, particularly in relation to their similarities with certain bacteria. His first paper in 1922 described the staining techniques for bacterial cells, and found that the techniques were equally good for staining mitochondria. He concluded that "bacteria and mitochondria have a similar chemical constitution". His subsequent paper (in the same year and same journal) further strengthened his assumptions. In addition, he observed in his study of blue green algae that chloroplasts are "bacteria or bacteria-like organisms that accepted the leisure of a symbiotic partnership in the struggle for existence". He made a summary conclusion that:

From the evidence that has been recorded in these studies, together with the evidence that may be found in mitochondrial literature, the author can arrive at no other conclusion than, that mitochondria are symbiotic bacteria in the cytoplasm of the cells of all higher organisms whose symbiotic existence had its inception at the dawn of phylogenetic evolution. The conception embodied in this conclusion presupposes that the establishment of new symbiotic complexes is coexistent with the development of new species. Wallin was aware that he needed to culture mitochondria isolated from cell in an independent environment. His early experiment was a failure using tissue samples from guinea pig, dog, and human blood. However, he succeeded in obtaining a mitochondrial culture with liver of fetal and newborn rabbits. He reported his findings in 1924 with a remark that "mitochondria are, in reality, bacterial organisms, symbiotically combined with the tissues of higher organisms." He continued with prolific publications. The series of his papers titled "On the nature of mitochondria" reached nine in 1925. He gave a full description of his experiments and theories on mitochondria in his 1927 book Symbionticism and the Origin of Species. Although he claimed that his experiments were performed with utmost care, critics rejected them on the grounds of possible contamination, and Wallin and his works were largely forgotten, until Lynn Margulis introduced a more complete endosymbiotic theory with better evidences in 1967.

Personal life Wallin married Eva Louise Shepard. Wallin was known for his eccentric behaviour in his professional life. He avoided lecturing, but instead used practical demonstrations. He frequently organised parties for his students, who in return helped him build a cabin in North St. Vrain Canyon, 20 miles north of Boulder. The parties were simply named "Club Wallin" which involved heavy drinking beside playing games. His notable habit was holding an annual Christmas glögg party. At the party guests were treated with Swedish delicacies such as sillsallad (pickled herring salad), lutefisk (dried codfish), and mulled wine.

Book Wallin, Ivan E (1927). Symbionticism and the origin of species. Baltimore: Williams & Wilkins Company. ISBN 9785872146940. {{cite book}}: ISBN / Date incompatibility (help)

References

External links Family history records

Worked examples

Example 1 — a first encounter with Ivan Wallin

Start with the simplest possible case. Write down what Ivan Wallin claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Ivan Wallin before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Ivan Wallin ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Ivan Wallin

In research
Ivan Wallin appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Ivan Wallin in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Ivan Wallin is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1883 births, 1969 deaths, American anatomists, so understanding it makes those chapters shorter.
In everyday life
Look for Ivan Wallin outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Ivan Wallin in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Ivan Wallin means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Ivan Wallin out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Ivan Wallin in simple terms?

Ivan Emanuel Wallin (22 January 1883 – 6 March 1969) was an American biologist who made the first experimental works on endosymbiotic theory. Nicknamed the "Mitochondria Man", he claimed that mitochondria, which are cell organelles, were once independent bacteria, as supported by his comparative st…

Why does Ivan Wallin matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Ivan Wallin?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Ivan Wallin.

Tags

  • 1883 births
  • 1969 deaths
  • American anatomists
  • Augustana College (Illinois) alumni
  • New York University alumni
  • People from Stanton, California
  • Princeton University alumni
  • Symbiogenesis researchers
  • University of Colorado School of Medicine faculty
  • University of Iowa alumni
  • University of Nebraska–Lincoln alumni
  • University of Nebraska–Lincoln faculty

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