Dr Dolphin – The Human Body

C O N T

FRONT COVERS

Did you submit a cover for the front competition? Find them here!

ARTICLES

WHAT IS ANAESTHESIA?

Learn more about anesthesia, and some of the history behind it!

THE HUMAN EYE

The eye: a fascinating organ. Here you can understand some of the basics to how it works.

BLOOD, HAEMOPHILIA & GENE THERAPY

Could gene therapy cure hemophilia?

THE LUNGS

The lungs are how we breathe! Read to learn more about gas exchange

GUT MICROBIOME & PERSONALITY

Does your gut microbiome affect your personality?

THE IMPORTANCE OF ENZYMES

What are enzymes and why are they so necessary?

STEM CELLS

Gain an insight to what stem cells are, and some of the issues surrounding them!

E N T S

DEBATE

CONSCIOUSNESS: A MATTER FOR SCIENCE OR PHILOSOPHY?

Should consciousness be considered scientific or philosophical?

QUIZZES

YEAR 7: CROSSWORD!

YEAR 8: QUIZ RACE!

YEAR 9: WORDSEARCH

YEAR 10: CROSSWORD

YEAR 11: GAP FILL

BONUS WORD SEARCH!

Dear Dolphins,

We hope you enjoy the February edition of Dr Dolphin!

Congratulations to everyone who submitted articles and magazine covers - they were all so amazing!

Editors:

~

Poppy Oppenheim

~

Xanthe Scott

~

Leila Savant

~ Sophia Williams

~ Lavinia Ricca

~ Dia Khosla

COVER COMPETITION!

Thank you to:

Luna Ozkan

Sarah Silva

Alessia Soso

Sanaya Mittal for their article contributions!

Luna Ozkan

Eleanor Sims

Victoire Nasser

Victoria Young

Victoria Young

Violeta Malpica

Prisha Mandav

Rachel Silva

WHAT IS ANAESTHESIA? HOW DOES IT WORK?

Anaesthesiology is one of the highest paying jobs, with an average salary in the UK of £92,000, but what do anaesthesiologists actually do?

Every patient needing anaesthesia has a different dose given to them, with many factors being taken into consideration, such as:

what type of surgery it is how long the surgery will take how old the patient is, etc

In order to take all of these factors into account, the anaesthesiologist comes up with an ‘anesthetic plan’, which typically includes pain control, amnesia (the patient doesn’t form any new memories), areflexia (the patient isn’t moving), and unconsciousness

There are three types of anaesthesia: regional, inhalation and intravenous Regional anaesthesia blocks pain signals (electrical impulses sent in the nervous system) from a specific part of the body from getting to the brain, by binding to the proteins in neurons’ cell membranes that let charged particles in and out, and allowing the flow of negatively charged ions into the cell, which then causes a build up of negative charge, thereby preventing the neuron from transmitting electrical signals. This means that regional anaesthetics only target one part of the body, rather than the whole body An example of a regional anaesthetic is cocaine, which was discovered by accident but is still occasionally used as an anaesthetic and has a similar chemical structure to regional anaesthetics

TInhalational anesthetics, however, work on the entire body including the brain to make you unconscious The way that these work is not completely understood, but they block the release of neurotransmitters. One of the first common inhalational anesthetics discovered in western medicine was diethyl ether, which at first was used recreationally until doctors realised that people didn’t notice injuries when under the influence. This led to the use of diethyl ether in dental extractions and surgeries in the 1840s

Usually inhalational anaesthesia is supplemented with intravenous anaesthesia, which was developed in the 1870s and includes sedatives like propofol, which causes unconsciousness, and opioids like fentanyl, which reduce pain. Intravenous anaesthesia affects the electrical signals in nervous systems and prevents certain parts of the brain from communicating with each other, causing unconsciousness; however there is a lot we still don’t know about how intravenous anaesthesias stop these parts of the brain from communicating.

XANTHE SCOTT

DR DOLPHIN: THE HUMAN BODY

One of the most famous inhalational gases, nitrous oxide, was discovered by a man named Humphrey Davy while working at the Pneumatic Institution in 1798, where he tested on himself the effects of inhaling this gas. He noticed the euphoric effect, making him laugh, and the fact that it alleviated the pain of his toothache He suggested the nitrous oxide could be used as an anaesthetic during surgery, but the medical community decided against this Instead, ‘laughing gas’ (as he called it) caught the public’s attention and gas inhaling ‘parties’ began. However, although Humphrey Davy’s work was dismissed in his time, it is still used in anaesthesia today.

Anaesthetics have a long history that can be traced back to many different regions, including the Babylonians, Greeks, Chinese and Incas During this time, all kinds of substances were tried out as anaesthetics, including alcohol, the opium poppy, cannabis, cocaine, and common poisons like hemlock and aconite. For example, the Incas used chewed coca leaves in the wound during trephination (bone or skull surgery), but it wasn’t until 1855 that cocaine was isolated from the coca plant and used as a local anaesthetic. However, if we move to the other side of the world, in the Sushruta Samhita (the ancient Indian medical text), the use of wine with incense of Indian hemp was advocated as a surgical sedative

Although there is still a lot to understand about anaesthesia, it’s importance in medicine has been made apparent, with many now-common practices having been enabled by anaesthetics, such as performing csections, replacing blocked arteries, damaged livers and kidneys, and many other life-saving operations

Every year, new anaesthesia techniques are developed, which is what makes anaesthesiology so interesting

4 XANTHE SCOTT DR DOLPHIN: THE HUMAN BODY

THE HUMAN EYE

The human eye is a sophisticated organ that allows you to see the world around you. But how does it work?

The eye has different parts that all participate and string together to allow you to see. One of these 'parts' is called the retina. The retina is a sensitive layering of tissue right of the back of the eye. When light hits the retina, there are special cells called photoreceptors that use these light rays and turn them into electrical signals. These signals travel from the retina through the optic nerve to the brain which turns the signals into the images we are able to see

What is color blindness?

Color blindness is almost always genetic. The words 'color blindness' are actually misleading, because color blind people can actually see color, just the colors lie closer together and are overall less vibrant Color blindness itself occurs because certain color sensitive cells, called cones, are either damaged or missing. The majority of color vision deficiency cases (color blindness) are because of genetic default.

How does light enter the eye in the first place?

The light enters the eye through the cornea. The cornea is a bit like a contact lesnse, in that it is clear, dome shaped, and covers the surface of the eye. From that cornea, the light then passes through the pupil onto the iris (the colored part of your eye) which controls how much light passes through to the retina

If you have ever shone a light near your eye (preferably don't) you will notice that the iris will become smaller This is the measure it takes to ensure that your eye isn't blinded or overwhelmed by light.

SARAH SILVA

DR DOLPHIN: THE HUMAN BODY

BLOOD, HAEMOPHILIA AND GENE THERAPY

Haemophilia A

Haemophilia is an inherited bleeding disorder which causes a mutation in the genes responsible for clotting blood There are two types: the first haemophilia A where the individual has a mutation in the gene that codes for factor VIII, the second haemophilia B where the individual has a mutation in the gene that codes for the IX factor. Mutations in either of these factors lead to similar issues including excessive and potentially fatal bleeding as a result of the blood's inability to clot. For the purpose of this article, I will be focusing solely on an emerging treatment for haemophilia A

Current treatments

Haemophilia A is traditionally treated with an infusion of the factor VIII every 2-3 days, meaning that on average 150 treatments are required every year. This is due to the short half life of factor VIII at an average of only 12 hours before its activity halves, hence the frequent infusions Several methods have been investigated to increase the half life of factor VIII infusions, including Fc fusion technology, which has been found to increase its half life by 1 5X, However, even with such technology patients still have to attend frequent appointments, posing an impractical and potentially expensive problem in their lives.

Gene therapy- the cure for haemophilia A?

A new and exciting gene therapy treatment has been developed to treat and potentially cure haemophilia A I will describe the treatment “valoctocogene roxaparvovec” , its benefits and finally its weaknesses. I will also comment upon potential areas of improvement, including alternative viral vectors and other delivery mechanisms that could instead be used.

Gene therapy is the modification of specific genes responsible for harmful mutations to cure or treat illnesses, via either “in vivo”, inside the body, or “ex vivo”, outside the body, methods “In vivo” gene therapy is when healthy genes from another specimen, which the patient lacks, are delivered to the patient via a genetically modified “vector” and integrate themselves into the recipient's genome “Ex vivo” gene therapy is when a mutated gene is removed from the patient's genome, externally edited to correctly code for the specific protein, before being re-inserted back into the body utilising a genetically modified vector Valoctocogene roxaparvovec is an example of “in vivo” gene therapy. Patients receive a genetically engineered vector containing the gene that codes for factor VIII, which is mutated in those with haemophilia A This is a “one time treatment”, as once the healthy transgene has integrated itself into the patient's genome, in 88% of trial patients, their factor VIII levels were high enough that they were deemed to either have a mild case of the illness or to no longer have it at all.

DR DOLPHIN: THE HUMAN BODY

Use of a viral vector

The vector, sometimes referred to as the “delivery vehicle” of gene therapy, in this particular treatment is an adenosine virus. It is modified so that harmful, viral DNA is removed to prevent the virus from causing illness. The transgene, in this case the gene that codes for factor VIII, is inserted into the genome of the virus The genetically modified virus containing the gene coding for the factor VIII can then be injected into the patient, allowing the virus containing the desired transgene to infect cells and replicate Factor VIII as a result can be correctly transcribed in the body to allow for clotting factors to be produced and prevent excessive bleeding associated with haemophilia

However, a side effect noted in some patients during the trial highlights a key issue in using viral vectors as part of gene therapy treatments. Some patients were found to have elevated liver enzymes as a result of receiving the therapy This implies that although all harmful DNA would have been removed from the adenovirus vector, an immune response was still carried out by the body having recognised the antigens on the surface of the virus and deeming it “harmful” and in need of destruction by the immune system. Evidently, this is problematic as should the body launch an immune response, the viral vector containing the needed transgene would be destroyed ultimately defeating the purpose of the treatment.

While immunosuppressants are often used in gene therapy to weaken the body's immune system such that it no longer attacks the virus, in a chronically ill patient, including those with haemophilia A, this is a risky approach as weakening the immune system also leaves them susceptible to other harmful infections.

An alternate way of avoiding this inflammatory immune response might be to use a different viral vector, perhaps the adenosine associated virus This virus has been found to be less immunogenic than other viral vectors, hence increasing the odds of the virus surviving in the body to successfully deliver the transgene by evading the immune system Other studies have even suggested utilising different methods of transgene delivery altogether These include sonoporation, whereby ultrasound waves are utilised to make cell membranes more permeable and furthermore to guide a “micro bubble” containing the transgene to the target cells, or electroporation, utilising an electric field to create small pores in the cell’s membrane again to allow the transgene to enter the cell. These “physical” delivery methods are arguably better than using viral vectors as although they come with their own risks, They avoid the issue of an immune response as discussed above

DR DOLPHIN: THE HUMAN BODY

THE LUNGS

The lungs are the organs that are part of the RESPIRATORY SYSTEM! The respiratory system is what we use to breathe and stay alive by providing our bodies with oxygen. Everybody knows that, right? But do you know what actually happens in the respiratory system?

Respiration is all about getting oxygen into your tissues (not the ones you sneeze into) Oxygen is what keeps them going each and every single day. The things you do in your daily life, like moving, eating, thinking, playing and just generally doing stuff, are all possible because of O (oxygen, not the mobile phone network) The process of respiration releases energy in the form of ATP in all living organisms. ATP stands for Adenosine TriPhosphate. It is used as a short term energy store inside cells, ATP is broken down to release energy and this energy is used in various processes that occur within a cell

Breathing in, (INHALATION)

1. External intercostal muscles contract, expanding the rib cage

2 Rib cage moves up and out

3. Diaphragm contracts and flattens, pulling down

4 Volume of the thorax increases

5. Pressure inside the thorax decreases so that...

6 Air is drawn into the lungs through the nose and/or mouth

Aerobic respiration:

glucose + oxygen → carbon dioxide + water (+ATP)

C H O + 6O → 6CO + 6H O

Oxygen is present

Oxidization of glucose is complete

Reactants of respiration are glucose and oxygen

Breathing out, (EXHALATION)

1. External intercostal muscles relax, dropping the rib cage downwards and inwards

2. Rib cage moves down and in

3. Diaphragm relaxes and moves upwards becoming dome shaped

4. Volume of the thorax decreases

5 Pressure inside the thorax increases so that

6. Air is forced out of he lungs and leaves through the nose and/or mouth

Products of respiration are carbon dioxide and water (and ATP)

There is a large amount of ATP made!

A molecule of air’s journey...

The molecule of air would first travel past the larynx, down the trachea, past the rings of cartilage and into a lung

Then, it travels into a bronchus, then a bronchiole and finally into the alveoli, which allow gas exchange to occur and for the molecule of air to diffuse into your blood vessels and then into your cells

Adaptations of the ALVEOLI:

Thin walls: alveolar walls are one cell thick providing gases with a short diffusion distance

Large surface area: many alveoli are present in the lungs with a shape that further increases surface area

Moist walls: gases dissolve in the moisture helping them to pass across the gas exchange surface/ speeds up the diffusion

Permeable walls - allow gases to pass through

WHY DO LARGE, COMPLEX MULTICELLULAR ORAGANISMS REQUIRE SPECIALISED BREATHING SYSTEMS?

As the size of an organism increases, it’s surface area to volume ratio decreases. This means it has relatively low surface area available for substances to diffuse through, so the rate of diffusion may not be fast enough to meet its cells requirements. Large multicellular organisms therefore cannot rely on diffusion alone to supply their oxygen and therefore require specialised breathing systems

WHAT ARE THE DIFERENCES IN COMPOSITION OF THE AIR, IN THE AIR WE INHALE AND THE AIR WE EXHALE?

When we exhale, the composition of the air is almost completely the same as the air we inhale Only the percentage of carbon dioxide and the percentage of oxygen changes.

Inhalation

Oxygen: 21%

Carbon dioxide: 0 03%

Exhalation

Oxygen: 16%

Carbon dioxide: 4%

HOW THE GUT MICROBIOME COULD AFFECT PERSONALITY

You are what you eat: how the gut microbiome could affect personality.

The microbiome consists of trillions of microorganisms including bacteria, fungi, parasites and viruses. The largest number of these microbiota are in the small and large intestines, forming a symbiotic relationship with the human body in which both benefit from their relationship.

The microbiota are given a prime habitat in which to thrive, and, in doing so, carry out a range of functions such as stimulating the immune system, breaking down compounds from foods that may become toxic, and synthesising certain vitamins and amino acids. If there is a disturbance in the balance of microorganisms in the gut due to infectious illnesses, certain diets and bacteria destroying medications, dysbiosis occurs and the body may become more susceptible to disease.

The ratio and strains of microorganisms present are due to a number of factors. Scientists estimate that 50% of this is down to genetics, however the microbiome can also be affected by diet and medication Antibiotics and other medications that kill bacteria have the most notable effect, decreasing the diversity and size of the microbiome, however probiotics can introduce bacteria and scientists also suggest consuming 30 different plants (including fruits, vegetables, grains and nuts) a week for optimal gut health to increase biodiversity.

Whilst it is well known that this supporting organ has big effects on the health of an organism, studies have also more recently begun to look into its effects on personality. A wide range of studies have found links between personality and specific bacteria present in the gut, for example, those who are more sociable have been found to have a microbiome containing more diverse bacteria and larger numbers of it. The reason for this is still unknown, but some theorise that this is because being sociable increases exposure to bacteria, allowing for optimal gut health.

Dr Katerina Johnson of Oxford University’s Department of Experimental Psychology carried out an investigation of the effect of gut microbiome on personality in humans She found that gut microbiome composition and diversity were related to differences in personality. Most notable sociability and neuroticism. Research into the microbiome-gut-brain axis (the connection between gut bacteria and the brain) is increasing as further correlation between types of microbiota present and mental health conditions are found. Some studies have gone as far as to transplant the microbiota from one organism to another When researchers transferred faecal microbiota to a mouse strain known to be more “anxious and timid” from a strain of “bold and exploratory” mice, the timid mice showed decreased levels of anxiety and researchers noticed they became bolder The same results were found when bacteria was transferred the other way - the bold mice became less exploratory. This study suggests that the microbiota present are not just correlated with personality, but are a direct cause.

DR DOLPHIN: THE HUMAN BODY

Whilst it is still unclear how every individual strain of microbiota affects brain function, there are multiple possible mechanisms that could cause this Microorganisms may communicate with the brain via neural, immune and endocrine pathways and produce neuroactive chemicals that can modulate host neurotransmitter levels. It has been found that the levels of some types of bacteriodes in the microbiome are associated with the brain signatures of depression. GABA, a neurotransmitter that blocks impulses between nerve nerve cells in the brain can be bacterially derived People with anxiety and depression have lower levels of this neurotransmitter, so introducing bacteria that produce GABA into the gut microbiome could offer treatment for these chronic mental health issues Discovering which bacteria produce these neurotransmitters could play an important role in the future of mental health issues, considering that psychiatric illnesses are often comorbid with gastrointestinal problems Similarly, gut dysbiosis could lead to imbalances in neurotransmitters and inflammation or heightened activity of the hypothalamus pituitary-adrenal axis that regulates the stress response Diagnosing and treating gut dysbiosis as the cause of some mental health issues could result in a dramatic increase in quality of life for patients.

Professionals believe a further understanding of the gut microbiome could have a big effect on the future of medicine. Many chronic mental health conditions could, theoretically, be improved, or even cured with the introduction of different microbiota However, there has not been significant research to suggest that introducing microbiota into the gut causes long term changes in the microbiome. In fact, it has been found to only create short term changes In order for treatments to be effective long term, permanent lifestyle changes would have to occur.

WHY ENZYMES HAVE NEVER BEEN MORE IMPORTANT

From digesting the food we eat to releasing the energy we need to move, enzymes play countless fundamental roles in our everyday lives. However, the function of these biological catalysts is certainly not limited to our bodies, or even other living organisms; in fact, humans have been harnessing the power of enzymes to carry out both intracellular and extracellular processes for a large part of history. As time goes on, there is no doubt that these biological catalysts will grow in importance, helping us tackle worldwide concerns such as climate change and life-threatening medical conditions.

The first record we have of voluntary enzyme use traces back to over 7,000 years ago. By extracting a mixture of enzymes from the stomachs of goats, sheep and cows, and adding this to milk, people many millennia ago were able to (unknowingly!) catalyse the curdling process used to create cheese. The key enzyme in this mixture is called chymosin: binding to the protein k-casein in milk, chymosin acts as a pair of ‘molecular scissors’ It is the clipping action of this enzyme that causes the milk to curdle.

For lactose intolerant people, who make up 70% of the global population, enzymes are what facilitate the consumption of dairy products. Usually, the enzyme lactase is what breaks down lactose into glucose and galactose, two monosaccharides which can then be absorbed individually into the small intestine with no discomfort. However, lactose intolerant people have low/negligible levels of lactase, meaning the lactose molecules are not broken down until they reach the large intestine, where gut bacteria digest them As a side effect of the bacteria’s activity, some people will get painful symptoms such as bloating. To solve this problem, before selling dairy products, food companies break lactose down into glucose and galactose using extracellular lactase- this allows intolerant people to sustain their calcium and protein intake without experiencing side effects.

DR DOLPHIN: THE HUMAN BODY

The use of enzymes is not limited to the food industry. Januvia, also known as Sitagliptin, is a drug used to treat type 2 diabetes, and is made partially with enzymes Type 2 diabetes occurs when the body is unable to make enough insulin (the enzyme that converts glucose to glycogen), causing high blood sugar levels, or hypoglycemia. Sitagliptin, in part synthesised by coupled enzyme reactions, treats this by increasing the amount of insulin enzyme that your body produces.

Some disorders are caused by a single enzyme working improperly in the body An example of this would be Phenylketonuria, otherwise known as PKU, which is caused by a change in the phenylalanine hydroxylase (PAH) gene This gene helps create the enzyme needed to break down/ metabolise phenylalanine, one of the 20 common amino acids. People with PKU who ingest this amino acid can be subject to permanent intellectual disabilities as phenylalanine builds up in their blood and brain, causing severe damage This disorder is rendered all the more problematic by the fact that phenylalanine is present in poultry, seafood, nuts, dairy and eggs. Fortunately, new enzymes may enable people with PKU to eat whatever foods they wish; in fact, the FDA (Food and Drug Administration) recently approved Palynziq, a novel enzyme therapy which contains pegvaliase, a bacterial enzyme that can break down phenylalanine

Enzymes have also begun to be used to solve environmental issues such as climate change Recently, bacteria which produce plastic-degrading enzymes were discovered Efforts are already under way to produce improved versions of these enzymes, as these may then enable us to start breaking down the millions of tonnes of plastic going to waste in the world. At the same time, there are also enzymes that have been discovered and are being optimised to produce non-petroleum derived biodegradable plastic, which could give us a much more sustainable production pathway for this material and help us reduce the issue of plastic pollution.

There are many other environmental problems which could be solved by enzymes. Currently, 90% of the energy consumption of laundry machines is due to the water heating systems, which play a crucial role in the removal of stains on fabric Washing in cold water by using enzymes to break stains down instead of heat would save 32 million metric tonnes of carbon dioxide each year, the equivalent of the CO2 emitted by 6.3 million cars.

As the years go on and biotechnologies improve, there is no doubt that the role of enzymes will keep expanding, and that their importance will continue to grow in a multitude of different sectors

STEM CELLS

Stem Cells: what are they and how will they revolutionise the future?

What are stem cells?

Stem cells are self-renewing, undifferentiated cells that have the capability to divide and regenerate many more cells of the same type They are unspecialised cells which means they have many uses; they can differentiate into many specific types of cells to serve a particular function. Stem cells are found naturally in three categories.

Embryonic stem cells are totipotent cells found on the inside layer of an embryo that are not yet specialised They can produce all types of cells and have no limitations on what they can mature into. During a pregnancy, embryonic stem cells are important during the developmental stages; they create different vital tissues and organs allowing the embryo to grow.

Adult stem cells are slightly different to embryonic ones. They can be found in multiple places throughout an adult body, including in the bone marrow, skin or even the blood inside an umbilical cord Other organs such as the liver and the brain also store a few. However, unlike embryonic stem cells that are able to give rise to any new cell, adult stem cells are multipotent and limited to producing blood, skin, organ or muscle/nerve tissue cells This is due to them already being partially specialised which therefore limits their ability to fully differentiate. Adult stem cells are predominantly used to replace cells lost to damage and produce new cells for growth and repair The last type of stem cells are unique as they are not produced by animals- they are found in the root and shoot tips of plants These areas are constantly growing and so have a large supply of meristem cells Meristem cells are fully undifferentiated and can become any new cell required. Just one of these cells has the ability to produce a whole new plant.

The future of medicine and stem cells

In 2006, a turning point occurred around research into stem cells Scientists Yamanaka and Takahashi found it was possible to extract embryonic stem cells without endangering the foetus. This opened the door to a whole realm of possibilities within the medical field Stem cells have the potential to repair damaged organs and manage a wide range of diseases that previously had no treatment. This sort of care could mean a better quality of life for all those suffering from debilitating conditions Most of the minimal research into stem cells is focused around diseases such as Parkinson’s and Alzheimer’s with a small section also exploring strokes and paralysis.

Organ Donation

Stem cells have become more widely talked about within the medical world in more recent years, a lot of the discussion based around organ donation and transplants A third of all organs transplanted per year are lost due to the recipient rejecting the organ. The research into stem cells shows that they provide the ability to heal the damage caused during transplants therefore reducing the risk of a rejection Alongside this, tissue engineering using stem cells also has the ability to help doctors not just reduce the risk of rejection but eliminate the need for donation in the first place

Another large part of this field of research is exploring the possibility of creating new organs altogether extracorporeally. This would be a revolutionary discovery as it would solve all organ shortage problems- 17 organ donation candidates die per day due to no access to an organ. In addition to this, if the organ can be genetically built to match the recipient's body and genome, rejection risk would be completely eradicated

Unfortunately, results that can be obtained from this research will not be accessible for at least another 10 years as few studies meet the scientific criteria that allows them to be passed for common usage. The main study happening at the moment is based around replacing diseased/damaged hearts in mice A few select patients have been admitted into a human study, however so far the results are not very clear. At the moment, as much as research should be tailored to treating and solving problems within a medical scenario, a lot of research is going into demonstrating the safety and efficacy of stem cells instead. This is because, although stem cells creating new organs would be a revolutionary achievement, these sorts of treatments raise major ethical concerns

Blood Cancers and Disorders

Stem cell transplants are more widely recognised as bone marrow transplants. Bone marrow contains adult stem cells that are multipotent and differentiate to produce different types of blood cells including red and white blood cells These sorts of transplants can be life-saving to the recipient who might have a blood cancer or disorder, however the transplant rate is very low as it is extremely hard to find an appropriate match.

Cord Stem Cells

A blood bank organised by the NHS is attempting to increase access to stem cells through embryonic stem cells They are collecting leftover cells from umbilical cord and placenta blood which would otherwise be discarded and wasted This is called the “Cord Blood Bank” and the blood obtained is used to treat cancers, immune deficiencies and genetic disorders. The cord cells can be used to treat; malignancies- blood cancer such as leukaemia, bone marrow failure- where bone marrow no longer produces the required cells, haemoglobinopathies- blood disorders such as sickle cell disease, immunodeficiencies- when the immune system does not function normally and metabolic disorders that affect the breakdown of waste in the body. If stem cells could provide a treatment for even one of these disorders, millions of lives would be improved.

ALESSIA SOSO

DR DOLPHIN: THE HUMAN BODY

The problem with using and culturing stem cells in medicine is that as they are being processed, the cells could pick up a virus or a harmful mutation. When these cells are then transferred to a patient, the consequences could be catastrophic As with many newer treatments, stem cells also seem to have the possibility to increase the risk of cancer developing. This is why the research and uses of stem cells must be so closely monitored.

The Ethics of Stem Cells

Stem cells have become a topic often discussed in ethical debates. While there are no moral objections to using adult stem cells or cord stem cells, the use of embryonic stem cells causes a lot of controversy Questions such as; is it right to use embryonic cells? is it right to create embryos just to destroy them? should an embryo have the same rights as a person? come to light These questions mainly come up in a religious context, the arguments being similar to those of the pro-life abortion campaigns. As an embryo has the potential to become a human if implanted into a uterus, does this constitute as murder?

Many people are entirely against the use of embryonic stem cells, however the benefits of their use must also be discussed in great length before they are written off. The sheer number of people that would have an improved quality of life through stem cell treatments would be monumental- this research truly has the potential to treat and even cure some of the most horrible diseases a person can face. A senator in the US (Orrin Hatch) states that he believes human life begins in the womb, not a Petri dish or refrigerator and therefore these embryos that are routinely discarded should be used to improve and save lives. This sort of approach to utilising embryonic stem cells could potentially reduce the ethical dissension.

There is also an argument around the social implications of stem cells. This sort of treatment and research is extremely expensive Although, technically, it would be a resource open for the wider public to use, realistically, only richer patients could afford it. This creates a social divide between more and less privileged societies within healthcare, contributing to a problem that is already very commonly encountered in everyday life

In conclusion, whilst the use of stem cells is still a relatively new and controversial concept, it has the potential to reshape the future of medicine and treatment changing healthcare for the better.

ALESSIA SOSO

DR DOLPHIN: THE HUMAN BODY

MATTER FOR SCIENCE OR PHILOSOPHY?

As a society, we often use science as a tool to help us navigate life’s mysteries Science is undeniably useful as it provides us with empirical and rational explanations, however there are times in which science alone is not enough to provide clarity, such as the nature of human consciousness That is, man’s self-awareness of their relation between self and the universe. Therefore in my article, I will be assessing whether consciousness can be explained best as a biological or metaphysical phenomenon.

A purely scientific lens explains mental experiences entirely as physical processes: ‘the mind is nothing but the motions in certain parts of an organic mind’ Hence, science tells us that consciousness can easily be reduced down to neurological events that occur in our brain. For example, the feeling of excitement is a brain state caused by the chemical release of an adrenaline hormone, or the feeling of stress is catalysed by the release of cortisol. This links to the idea of monism: the mind and body are not separate substances but are in fact both part of the material world. A world that is, ultimately, biological. In this way, our mental states are identical to our physical states, and one could argue that consciousness is a biological phenomenon

However, there are limits to this view ‘Mary’s Room’ is a fascinating thought experiment proposed by Frank Jackson, which challenges the purely material conception of consciousness. Jackson asks us to imagine a girl called Mary who has lived in a black and white room her whole life, and has never witnessed the colour red. Mary educates herself on everything there is to know about vision and the neuroscience of the colour red. But, if she were to see a red apple for the first time, Jackson poses the question of whether she learns anything new. Despite the fact that she had obtained all of the physical information, it seems largely intuitive that Mary learnt something from witnessing the colour red, as it is an experience and sensation. Therefore we can conclude that there are elements to experience and knowledge that transcend fact. Moreover, the scientific view subscribes to the idea that everything belongs to a material world. However in order for this to be true, conscious states would need to possess material properties such as mass, shape, temporal/spatial locations. However these properties can not be applied to thoughts, sensations or feelings. This can be characterised as ‘qualia’. In light of this, I reject the physicalist depiction of human nature, as it leaves no room for an acknowledgement of qualia, and does not allow for differentiation between mental and physical states.

An alternative approach to this, is the theory of substance dualism proposed by Descartes. A dualist conception of what it means to be a human being suggests that all of us are composed of the mind and body which are two separate and distinct entities that can interact Dualists believe that these entities co-exist yet are fundamentally distinct due to their differing properties. For example, the body belongs to the physical world and is characterised by the fact that it is destructible and has material properties such as mass, shape, weight etc. By contrast, the mind is indestructible, as it belongs to the immaterial world, the mind has extension beyond precise locations in space

Hence, in contrast to physicalists, dualists believe that mental phenomena are non-physical states i.e consciousness is not irreducible to brain function, as the mind is not identical to the brain. Therefore, dualists would believe that the thought of someone walking is not simply triggered by the interaction of neurons in the brain, as it is a non-physical event In essence human beings belong to two separate realms: the material and the immaterial.

Whilst dualism acknowledges qualitative elements to consciousness, I believe that it is a theory that is inherently flawed This is because it fails to resolve the problem of interactionism It seems apparent that there is a relationship between our mind and body: my mental thought to raise my hand in class is then acted on by the physical deed of raising my hand, therefore our thoughts and actions are undeniably correlated As pointed out by Princess Eliazabeth of Bohemia , dualism fails to provide an adequate explanation for this relationship as if the mind is an immaterial substance how can it have causal influence over our body which exists in the spatial temporal world. Moreover, dualism disregards any biological components of consciousness, which seems implausible, as people who are brain dead experience consciousness differently

The philosopher Daniel Dennet sought to resolve the problem of interactionism through epiphenomenalism which states that consciousness emerges from brain functionality but is not reproducible down to it. Hence, whilst epiphenomenalism acknowledges physical states, (such as a light bulb striking your retina allowing you to witness a tree), it also explains that mental states are an emergent property of these physical processes, that have no causal influence over what happens in the brain and body. Thus, consciousness is something that supervenes on the processes that occur in the brain. Whilst this is not a perfect theory, it recognises both non-physical and physical elements to consciousness and provides a clear causal link between them, uniting the deeply philosophical with the scientific.

In conclusion, our subjective experiences are both defined by neurological events but also by the qualitative states that occur as a result of them (feeling of pain, smelling a rose, the redness of red) which can not be explained simply by physical facts. The question of what consciousness is undeniably one that will continue to puzzle academics. Maybe the answer lies somewhere in between. If this phenomenon teaches us anything, perhaps it indicates that it is time we stop viewing science and philosophy as incompatible fields, and instead develop an understanding of the ways in which both studies can enrich human understanding.

Year 8

-HOW FAST CAN YOU ANSWER THESE 10 QUESTIONS?-

1. WHAT IS THE SYMBOL EQUATION FOR AEROBIC RESPIRATION IN ANIMALS?

2. WHAT FORM IS ENERGY RELEASED IN LIVING ORGANISMS?

3. WHAT ARE THE 7 COMPONENTS OF A BALANCED DIET?

4. WHERE IS THE SITE OF GAS EXCHANGE IN HUMANS?

5. WHAT ARE TWO SOURCES OF VITAMIN A?

6. WHAT IS THE NAME OF THE CHEMICAL TEST FOR GLUCOSE?

7 WHAT ARE THE EFFECTS OF SMOKING ON THE ALVEOLI?

8. WHAT TYPE OF RESPIRATION OCCURS IN YEAST CELLS?

9. WHAT IS THE DIFFERENCE IN COMPOSITION BETWEEN INHALED AND EXHALED AIR?

10 IS YOUR BREATHING RATE HIGHER OR LOWER AFTER EXERCISE?

TIME: SCORE:

VEINS

Year 9

NITRATEIONS XYLEM

PHLOEM

HUMIDITY

WINDSPEED

TEMPERATURE

Year 10

Across:

7. The movement of particles through a cell membrane from a region of low concentration to a region of higher concentration using energy from respiration, , against a concentration gradient

8. Shouldn't be allowed to build up, molecules dissolve in water and lower the pH of cells

10 Where oxygenated blood leaves the heart

12. Makes up the layers of fatty acids (plaque) that build up in the coronary arteries

14. organ that excretes urea, water, and mineral ions

Down:

The net movement of molecules from a region of higher concentration to a region of lower concentration, down a concentration gradient

2. Glucose is reabsorbed at this tubule

3 A diet too high in this is the main cause of coronary heart disease

4 When this is high, it is a risk factor of coronary heart disease

5. This membrane is .... it only allows some molecules to cross

6. Deoxygenated blood enters the right atrium through the ...

9 Shape of red blood cells, increases surface area to volume ratio for higher rate of diffusion

11 The net movement of water molecules from a region of higher water potential to a region of lower water potential

Year 11

Cloning Gap Fill:

Cloning might occur to produce more of an endangered species, or to maintain a high quality of livestock in farming.

There are two ways in which animal cells can be cloned:

Animal embryo transplants

An cell is taken from the “best” female animal (ie one with desirable qualities). This cell is then by a sperm cell from the “best” male animal to form a , which quickly becomes an embryo The embryo is initially composed of cells, which are unspecialised cells Before these cells specialise, the embryo is to produce many clones of the embryo. Each embryo is then into a different host mother, who will carry the embryo until she gives birth. The offspring produced are all genetically to each other, however they share no genetic information with the surrogate mother

Adult cell cloning

This involves using only egg cells, and NO SPERM CELL, to produce an embryo. Firstly, the nucleus from an egg cell is removed A nucleus from an adult cell with a chromosome number is inserted into this egg cell. This ensures that the egg cell has the correct number of chromosomes as it will not combine with a sperm cell to achieve this number, which in humans is . A small shock is applied to the modified egg cell. This causes the egg cell to to form an embryo Once the embryo has divided to form a ball of cells, it is inserted into a mother, where it will continue to develop until birth. It is important to note that the embryo contains the genetic material of the cell nucleus, and hence it is genetically identical to it.

Bonus Wordsearch!

THE PROCESS BY WHICH A CELL TAKES IN NUTRIENTS, GETS RID OF WASTE AND PERFORMS

OTHER FUNCTIONS

THE ORGAN THAT FILTERS BLOOD TO REMOVE WASTE PRODUCTS AND EXCESS WATER. THIS TYPE OF CELL IS THE BASIC UNIT OF LIFE AND IS FOUND IN ALL LIVING ORGANISMS

THE STRUCTURE IN CELLS THAT CONTAINS GENETIC MATERIAL

THE ORGANELLE RESPONSIBLE FOR PRODUCING ENERGY IN CELLS THROUGH CELLULAR RESPIRATION

THE PROCESS BY WHICH AN ORGANISM PASSES ON ITS GENETIC INFORMATION TO ITS OFFSPRING

THE STUDY OF THE CAUSES, DIAGNOSIS, AND TREATMENT OF DISEASES

WHAT IS THE PROCESS OF CELL DIVISION IN WHICH THE NUMBER OF CHROMOSOMES IN A CELL IS REDUCED BY HALF?

WHAT IS THE NAME OF THE CELL STRUCTURE IN PLANT CELLS THAT ALLOWS THEM TO CARRY OUT PHOTOSYNTHESIS?

WHAT DISEASE IS CAUSED BY VITAMIN C DEFICIENCY?