The heart of the matter

Heart doctor Michael Henein steps back to consider the unseen and unique wonders of the human body’s design.

Michael Henein

Professor Michael Henein is a consultant cardiologist, and a Professor of Cardiology at Umea University, Sweden.

A model of a human heart on a short stand.

Photo by Jesse Orrico on Unsplash.

Shakespeare famously asked:

“What a piece of work is a man, how noble in reason, how
infinite in faculties, in form and moving how express and admirable, in action how like an angel, in apprehension how like a god! the beauty of the world, the paragon of animals—and yet, to me, what is this quintessence of dust?

Humans may be complex, capable of great heroism and deep depravity, yet it is worth stopping for a moment to look at the human body and mind to marvel in what we have become, and how we are made.

The visible design of the human body points out common features shared along with other members of the animal kingdom. Examples of these features are: two eyes, two ears, two nostrils, one mouth and four limbs, attached to a body and head. Detailed study of different seen parts of the body may, however, show some differences. For example, the presence of fingers and nails, hair distribution as well as a developed tail. While most members of the animal kingdom have teeth and a tongue, those two could also vary in their number and size, respectively, according to different species. Genetic investigations have shown that we humans share 99 % of our genes with animals, suggesting that our “earthly” component shares a common origin. Indeed, the twenty first century scientific findings match what is written in the Genesis story of creation, a story written over 3,500 years ago, well before genetic sciences came to light.

Creatures great and small

As for morphological differences between animal species, it is difficult to naively conclude why some are wild while others are man-friendly-even if the wild ones have different shapes, design, dietary habits, body size and life span. Other important observed features of the members of the animal kingdom are that they are all born, they all age, then ultimately die.

If we are to look at the unseen features of the members of the animal kingdom, we can again identify similarities. For example, all have a gastrointestinal tract, a cardiovascular system, a reproductive system, a respiratory system, a urinary system and much more. While these systems may differ slightly between species, the overall structure and function achieve similar purposes. For example, heart speed is faster in small animals like rats compared to big ones like elephants who have very slow hearts. Likewise, the respiratory system and the number of respiratory cycles per minute are significantly faster in running animals compared to the sedentary and slowly moving ones. Finally, the number of offspring also differs in different species, being just one at a time in big animals like elephants and horses, and many offspring in small animals like rabbits and mice. Such paradox between the number of offspring and animal size makes you think of the important determining role of the activity of those animals.

Unseen wonders

Now to turn to the rest of the animal kingdom and the unseen features of the human body. To start, let us look at the amazing functions of the human brain and its various functions. When humanity is sometimes described as the crown of creation, such a description is based on the superiority of human brain function and skills. Its sophisticated structure and how vital centres are created deep in the skull, to be protected from traumas, make you marvel. Also, the brain controls the different functions of the whole body, with its sensory and motor activities, various vital system functions including the lungs and the heart, all endocrine glands’ function, in addition to various receptors and centres that allow utmost precision and accuracy in everything we do. An example of this kind of precision is a doctor feeling a vein or an artery with the tip of a finger to insert a needle or a musician moving a finger a few millimetres while playing a violin, to produce the exact sound needed. Furthermore, the integrated function of human muscles, nerves and spinal cord is also amazing, let alone the synapsis between the nerve endings and muscle bundles, the chemicals secreted in them which allow electric stimulus transmission from the nervous system to achieve the motor function and desired movement.

The human brain also has the unique feature of storing knowledge. Of course, we should not ignore the importance of the training and programming ability of human brain. We learn how to drive a car, how to play games, how to study, how to operate safely on a sick patient. Such acquired skills are quite limited in other members of the animal kingdom. Moreover, the human brain has the unique ability to invent, discover, improve and correct errors it identifies.

Another very unique feature of human brain is its ability to conduct speech, a feature of humans that is under-developed in other members of the animal kingdom. While most animals can make noise and sounds, only humans can articulate words, sentences and even sing very complex songs. This unique ability seems to be the underlying mechanism behind the development of languages which are based on the human ability to talk and transmit information and knowledge by words and phrases.

The unseen brain has allowed human life to develop over time, building skills and achievements from generation to generation. Millennia ago, humans lived in huts together with animals, and now they build houses and palaces to live in. Centuries ago, we used donkeys, horses and camels to travel but now we use cars, trains, ships and airplanes. Our ancestors burned wood and coal to cook and to warm but now we use electricity to do these.

When we look carefully at the unseen parts of the human body, we also realize that we cannot alter any of it, despite the scientific advances made over the years. We can understand what harms our body and take measures to avoid it. Out of the ability of our brain to discover and invent, we have now produced science-based means for curing various diseases. Consider how we can replace a dysfunctional heart valve or a mobility-limiting joint. These inventions have resulted in a better quality of life, alleviating of symptoms, even helping to avoid early death, in some cases such as heart disease and cancer.

The heart of the matter

Another unseen source of life in humans is the heart. This fist-size organ is so complex in its structure and function. Recent scientific advances have enabled us to study heart function in milliseconds, hence the development of pacemaker treatments. They have also allowed clear imaging of the inside of the heart and the identification of pathologies, developments that guide practitioners to the optimum treatment of heart conditions. Recent discoveries have also allowed us to better understand how people develop coronary artery disease and how the pathology starts at the innermost layer of the arteries, particularly in individuals carrying significant risks for atherosclerosis including, smoking, high blood pressure, diabetes, high cholesterol and obesity. Amazingly, obesity has been shown to be the strongest underlying cause of other risk factors, hypertension, diabetes and hypercholesterolemia. So, nature cannot be blamed in many of these patients but our own patterns of behaviour. Science has shown that walking at least 5,000 steps each day, complying with the design of our body, reduces the likelihood of developing coronary artery disease by 15 per cent.

The unseen physiology of the rest of our body systems and the interaction between systems make us wonder how we are made. A rise of our body temperature by one degree due to a bug infection affects all body systems from the brain to the heart. A virus which cannot be seen by the most powerful microscope can destroy our lungs and cause premature death, as was the case with COVID-19 and others.

Finally, human inventions in the form of powerful microscopes have allowed scientists to study the human cell, which is the smallest living component of our body. Such small cells cannot be replicated in any factory in the twenty-first century, despite the vast scientific developments that surround us. You'll be surprised to learn how complicated and meticulously fine-tuned a human cell is and also how it functions, connects with other cells and other parts of the body. An example of this is the interaction between body minerals, calcium, sodium and potassium with heart and muscle individual cells. Such a function is critically controlled by many factors such as time, electric stimulation and pressure differences producing remarkably harmonious contractions and relaxation of the muscles without missing a beat.

Article

Character

Comment

Education

Fun & play

1 September 2025

5 min read

Is your child school ready?

What really matters as a child develops

Henna Cundill

Henna is a researcher with the Centre for Autism and Theology at the University of Aberdeen.

A teacher looks on as a young child concentrates on writing.

Department for Education.

In the coming weeks, those little critters will start to emerge, easily identified by their autumn plumage of coloured sweatshirts and oversized backpacks. Anxious parents and caregivers can be spotted, shepherding their young along paths and pavements, casting worried glances left and right at the pelican crossings. Listen carefully and you may hear the squeak of uncomfortable new shoes and juveniles complaining about the wearing of a coat, as adults of the species re-establish social bonds with cries of, “Back to school already, I can’t believe how fast it’s gone!”

As they congregate upon the tarmac staging ground, some will be taking part in this ritual for the very first time. Neophytes who have maintained social bonds throughout the pre-school years might be seen to greet their fellows cordially, “Did you have a good summer? Can Flo make it to Izzy’s party?” Others will stand alone, scanning the playground for a half-remembered face from the bygone days of antenatal classes. That was only five years ago, but it feels like a millennium. The faces are changed; everyone looks more…tired.

The world has been turned upside down in those past five years. It’s been said so often that it is almost trite, but nonetheless true: nothing prepares you for becoming a parent. In the UK, new parents increasingly raise their children without the immediate support of extended family, coupled with the tyrannous expectation that one will retain one’s employment rank and contribution to the labour market alongside this new and 24/7 full time job of looking after baby. The Key Performance Indicators of parenting are ambitious. Deliverables for the first five years include toilet training, instilling speech and language skills, establishing basic recognition of 26 alphabetical characters (including the child’s ability to recognise the alphabetical sequence that spells their own name) and ensuring the recognition of and (ideally) ability to correctly sequence numbers 1 to 20. If your child can do all of this by the age of 5, whilst also learning not to punch, kick or bite other children, not to eat food off the ground, and not to stick rocks up their nose, then congratulations! Your child is school ready!

It may comfort some readers to know that very few 5-year-olds manage to hit absolutely all of these milestones. As the education secretary, Bridget Phillipson, commented recently – parenting is too hard. She is working to establish a new iteration of Labour’s ‘Sure Start’ programme (rebranded as ‘Family Hubs’) to offer parents more support in the community. As part of her rationale she states, “When one in four children are leaving primary school without having reached a good level of reading, then something’s gone seriously wrong in those early years that has to go beyond the school gate.”

Whilst I’m keen to see more support for new families – I’m intrigued by this particular rationale for it. Ability to read well by a certain age seems an unlikely metric by which to measure whether a child has had a positive experience of childhood; it appears indicative of what autism-researcher Anne McGuire calls “The normative time of childhood,” in which the success is measured against an imagined future of economically productive years. By this metric, if a child learns to read at a prodigiously young age this is taken as an indicator that they will enter the workforce with greater velocity than their peers, essentially that they will have “more future-yet-to-be-realized” than those around them. McGuire writes, “In a neoliberal regime where ‘time is money’, the child is figured as ‘time-rich’ and so represents a good investment opportunity indeed.”

McGuire’s analysis is piercingly accurate of how we often talk about our children, despite knowing all too well that it represents a fallacy. There are multitudinous stories of adults who have gone on to make staggering contributions to human flourishing, despite being placed (literally or figuratively) under the dunce’s cap at school. But even without focusing on those who go on to excel, those who attract fame, fortune, or both, we don’t have to look far to find cause to re-evaluate what it means for a child to be school ready.

My son’s year group recently finished their own primary school journey, and a quick glance through some of the leavers’ books reveals that children are very good at valuing each other for what is here in the present, without recourse to an imagined economic future. As children wrote goodbye messages for each other they said things like,

“Thank you for always having such good ideas for games to play.”

“You helped me on my first day when I got lost.”

“You’re a great house captain and you always help the teacher.”

No one was particularly keen to predict fame and fortune for the future of their friends, and there was an understandable indifference towards academic milestones. As a literary corpus, the leavers’ books were testament to the old adage that people will not remember you for what you say or do but will remember you for how you make them feel.

One the subject of childhood, Jesus once said something that defies easy explanation. He was out, teaching in the open air, surrounded by crowds of adults including important religious leaders and wealthy individuals who wanted to ask complex and deep theological questions, but in the midst of it all there were parents bringing their children, elbowing their way to the front of the crowd to ask Jesus to pray for their little ones. When some of Jesus’ followers tried to usher the children away, Jesus said, “Let the little children come to me, and do not hinder them, for the kingdom of heaven belongs to such as these.” The precise meaning of this utterance has eluded thinkers and theologians for centuries – what exactly is it about childhood that Jesus was alluding to?

I wonder if it is something about the capacity of children to live in the immediate, and therefore to value what really matters – justice, kindness and friendship. In primary school, yes it helps in some ways for children to arrive aged 5 with a certain command of the alphabet and the ability to finish the day wearing the same set of underwear that they arrived in. But perhaps what matters more is children arriving ready to enter the fray of friendships – being kind, being helpers, having the self-confidence to know that they have something to give to the learning community that they are joining, whatever their learning speed might be. Such things are gloriously untethered to economic potential or a future-yet-to-be-realized, but they are closely tethered to a child’s understanding of themselves as a valuable and important person. If Labour’s intention to offer new parents more help in the community goes some way towards communicating to our pre-school children that they have that have – and will always have – value, regardless of what they will or won’t attain to academically or economically, then it will help many more children reach the milestone of being school ready.

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