A companion website for those studying the human body scientifically - its anatomy, its physiology and its meaning in the world - being the thoughts (and reminiscences) of a retired anatomist.
Tuesday, September 3, 2024
A headache when passing water
Tuesday, August 27, 2024
Reconstruction
I previously described how I originally considered calling this blog, ‘Deconstructing Humpty’ and often think in terms of ‘Reconstructing Humpty’. This naturally raises the question of what these phrases imply. I have discussed deconstruction. What does the phrase ‘Reconstructing Humpty’ mean?
I am sure that it can mean different things to different people. Not all of these have been explored fully by me. There may also be meanings of which I am unaware. However, one meaning important to me is that of a ‘re-imagining’. It means developing a new mental image or impression of what we are dealing with - the human body as seen from a primarily scientific perspective.
Furthermore, I suggest that Reconstructing Humpty implies a ‘re-construing’. When learning Latin at school, children were often given a passage of text and told to ‘construe’. Put simply this means ‘translate’. However, merely swapping Latin words for English is not enough. One must also ‘interpret’. That is, one must convey the meaning that was intended by the writer of the passage in question. This means using the most appropriate words in the best possible way.
Thus the idea of ‘construction’ is not out of place here. An interpretation is a reconstruction - in a different language - of something previously constructed in another. To construe things about the human body is to interpret what we find. As part of this, we must ask whether we currently have the best or most accurate interpretation of what the body is like.
Monday, August 19, 2024
FAQs - An alternative (1)
As described elsewhere on this blog, the abbreviation FAQ stands for ‘Frequently Asked Question’. It is often seen on websites. It is a way of providing the visitor with key information quickly and easily. The intention of such questions is not to prompt further questions or inspire anything akin to contemplation. That is the job of a quite different type of question.
These are questions that often get asked again and again. That type of question might be called an FAQ with those letters this time standing for ‘Frequently Addressed Question’. Such questions typically resist satisfactory answers. They are the deeper, perennial questions about life (…the Universe and Everything).
These questions certainly cannot be answered quickly and easily. They have been asked by succeeding generations of thinkers. Thus, they may rightly be called Frequently Addressed Questions. A Frequently Addressed Question is one to which we return again and again not necessarily expecting an answer. The benefit of unanswered questions is that they open up new avenues of thought; they prompt new ideas.
In relation to the human body, what are (or should be) the Frequently Addressed Questions?
This, in itself, may be the first such question. We should ask repeatedly, ‘In relation to the human body, what are (or should be) the Frequently Addressed Questions?’
I come to such questions from a scientific perspective but there are others. Our different perspectives are not mutually exclusive nor should they be kept entirely separate.
Sunday, August 11, 2024
Sinnott Quote
Let us never grow so pedantic that we shall frown on any brother who occasionally goes off the reservation of biological orthodoxy to refresh himself in other fields. He may bring back from his excursion a treasure which those who stay at home can never find.
The Cell and the Problem of Organization
Science
20 Jan 1939
Vol 89, Issue 2299
pp. 41-46
Saturday, August 3, 2024
The Le Chatelier principle
Further to the considerations about homeostasis made on this blog, I was reading some books by Edmund Sinnott (1888-1968) recently in which he raises the question of biological organisation and its maintenance. Sinnott is not somebody well known to biologists - at least in the UK. I only came across him because of a quote of his used by JH Woodger (1894-1981) in his book ‘Biology and Language: An introduction to the methodology of the biological sciences including medicine’ (Cambridge University Press, 1952). In what I read, Sinnott raised the question of the biological role played by Le Chatelier’s principle.
A concise definition of Le Chatelier's principle from Merriam-Webster Dictionary (and cited on Wikipedia) is as follows,
If the equilibrium of a system is disturbed by a change in one or more of the determining factors (such as temperature, pressure, or concentration) the system tends to adjust itself to a new equilibrium by counteracting as far as possible the effect of the change.
The question Sinnott asks is to what extent chemical phenomena, such as Le Chatelier’s principle, contribute to the emergence of homeostasis. Le Chatelier’s principle arises out of the nature of physico-chemical phenomena; homeostasis is a product of the way in which the body is organised. Does the latter arise out of the former?
Le Chatelier's principle is not something widely discussed in undergraduate biology. I do not recollect it being mentioned even as part of the biochemistry courses I followed. However, the notion of biochemical equilibrium was mentioned - albeit from a purely (bio)chemical perspective. The focus was always on - what might be called - the behaviour of the chemistry. That these might feed into a higher level - more organised - stability was not explored.
Saturday, July 27, 2024
The Schematic Circulation of the Blood
Another diagram found almost ubiquitously in textbooks of anatomy and physiology is a schematic representation of the circulation(s) of the blood. I say 'almost ubiquitously' because I have never found a textbook in which some such diagram has never appeared... but there may be one out there somewhere. I also use the word 'circulation(s)' because human blood circulates in a figure of eight. One circuit is referred to as the systemic circulation, the other the pulmonary circulation.
Despite the conceptual simplicity of the circulation of the blood, the diagrams one finds in textbooks vary markedly. I shall share some of those I have collected from time to time. To begin, this version comes from Wikipedia:
As with all diagrams, there is simplification, conceptualisation and questions arising as a result. The more commonly a diagram is found in a textbook, the more it should be scrutinised. New textbooks take their lead from old textbooks. Some things are included because they have always been included; their exclusion might be deemed an omission. (Nobody wants a bad review.)
Is this the best such diagram? Does it make its point as well as it could?
Friday, July 19, 2024
Cells typically stay separate
Cells are often described as the smallest unit of life. That applies to both uni- and multicellular organisms. This is a characteristic they maintain as long as they survive. As such, they possess an ‘individuality’.
To the benefit of the organism as a whole, some cells divide while others, also to the benefit of the organism, do not. Still others may usefully disintegrate - as in the case of megakaryocytes which give rise to platelets important in blood clotting.
Obvious - yet rarely stated - is the fact that cells do not typically merge with other cells. Here, the fusion of sperm and ova is seen as a special case. Each contains only 23 chromosomes and so only half of the entire genetic material. Thus, sperm and ova are - in a sense - only half cells. (Indeed, whether sperm qualify for the title ‘cell’ is a moot point.)
With very few exceptions, cells remain separate from each other throughout their lifespan. They do not blend or merge to form mega-cells. Those cells that do fuse do not fuse with cells of another type. They fuse only with cells of the same type. In so doing they become multinucleated. The cytoplasm is combined but not the nuclei. In this, a hint of the ‘individuality’ I mentioned above, persists.
What does having two nuclei within the same cytoplasm imply? In practical terms, there is an increase in the efficiency of the cell. (If by cell we mean that bounded by the cell membrane.) It implies double input/output and information processing capacity.
Those cells in our bodies that do undergo fusion do so in specialized circumstances, such as during development and tissue repair. For example:
- Muscle Cells: Muscle cells, known as myocytes, can fuse to form multinucleated muscle fibres. This process contributes to the growth and repair of skeletal muscle tissue.
- Osteoclasts: Osteoclasts, which are responsible for bone resorption, are formed by the fusion of monocyte/macrophage precursor cells.
- Syncytiotrophoblasts: In the placenta, syncytiotrophoblasts are formed by the fusion of cytotrophoblasts. These multinucleated cells play a crucial role in facilitating nutrient and gas exchange between the maternal and fetal circulations.
Cell fusion is not a random process. It is tightly regulated and involves complex molecular mechanisms. This implies that cell fusion is a process that has evolved. As such, it offers the organism a biological - that is, a survival and/or reproductive - benefit. To use a word rarely used biologically, it is ‘deliberate’.
Having introduced this word, I will stop here and ponder what, in a biological context, ‘deliberate’ means and how it might be used.
