Workbook (Cells): https://docs.google.com/a/sst.edu.sg/file/d/0Bz_vGtwO7-4ZV0FzT010VkZnOUE/view
Practical Workbook (Cells & Microscopy): https://docs.google.com/a/sst.edu.sg/file/d/0Bz_vGtwO7-4ZRFE4UGszdnBydlU/view
Practice Worksheet: https://docs.google.com/a/sst.edu.sg/file/d/0Bz_vGtwO7-4ZUDMtOEc1ZlhfODA/view
Hierarchy of Cells Worksheet: https://docs.google.com/a/sst.edu.sg/file/d/0Bz_vGtwO7-4ZdVd5UWxJTEFVVkk/view
Thursday 24 January 2013
Monday 14 January 2013
Definition of Death - Grp 4
Link to presentation : https://docs.google.com/presentation/d/1wLZqgbQDOjcboqJrf1maU-A0j8nHfEQXTi3P9W8HrmU/edit
The Definition of Life
1. To be legally dead means when a person disappears and no identifiable remains can be located, and is subsequently declared legally dead. A legal death can also be a legal pronouncement by a qualified person that further medical care is not appropriate and that a patient should be considered dead under the law.
To be medically dead means the cessation of blood circulation and breathing, the two necessary criteria to sustain life. Should one have these symptoms, one should be declared dead.
Example: Mr Chua has stopped breathing and his pulse has stopped, is he dead?
2. Definitions of death have not changed a great deal, but that doesn't mean much. All we can really do is set criteria for who's dead, and that is tough enough, and we have no real definitive set of standards.
Different cultures have different ways of accepting death and different procedures to follow after the confirmation of death. Some believe in reincarnation and some believe a following into heaven or hell.
Example: Mr Chua has been declared dead, is he in heaven or attained nirvana?
3. Brain death occurs when a person no longer has any activity in their brain stem and no potential for consciousness, even though a ventilator is keeping their heart beating and oxygen circulating through their blood. When brain stem function is permanently lost, the person will be confirmed dead.
Brain dead is the irreversible end of all brain activity. Some of the criteria would be the person being unresponsive. There will be no facial sensation or response. There would be no response to light directly in their eyes.
Example: Mr Chua is dead, can he still sneeze?
4. Someone in a persistent vegetative state can show signs of wakefulness (they may open their eyes, for example) but have no response to their surroundings.
However, the important difference between PVS and brain death is that a patient with PVS still has a functioning brain stem, therefore:
Some form of consciousness may exist in someone in a PVS.
A person in a PVS can still breathe unaided.
A person in a PVS has a slim chance of recovering because the core functions of the brain stem are often unaffected, whereas a person with brain death has no chance of recovery as the body cannot survive without artificial support.
Example: Mr Chua has been in a coma for 3 years, yet he is still breathing and his core functions are still functioning, is he dead or in a vegetative state?
5. There is no strict way of defining death. Some of the other ethical issues would be concerning the certainty of diagnosis and about the medical steps that may be taken after death is pronounced. The definition of death is a moral issue and that confronting it as such vindicates the higher-brain approach.
For example, in the past, people were declared dead if organs were missing. However, due to technological advancements, organ transplants and blood transfusions have been made possible and have allowed people in near-death situations to survive. This has led to the ethical implication of people surviving when they should have been dead instead.
Human organs have been made possible to replace with other animal organs such as pigs, who have similar organs as people.
Example: Mr Chua’s organs are missing, is he dead?
By: Carissa, Chang Han, River, Crystal and Desiree :)
To be medically dead means the cessation of blood circulation and breathing, the two necessary criteria to sustain life. Should one have these symptoms, one should be declared dead.
Example: Mr Chua has stopped breathing and his pulse has stopped, is he dead?
2. Definitions of death have not changed a great deal, but that doesn't mean much. All we can really do is set criteria for who's dead, and that is tough enough, and we have no real definitive set of standards.
Different cultures have different ways of accepting death and different procedures to follow after the confirmation of death. Some believe in reincarnation and some believe a following into heaven or hell.
Example: Mr Chua has been declared dead, is he in heaven or attained nirvana?
3. Brain death occurs when a person no longer has any activity in their brain stem and no potential for consciousness, even though a ventilator is keeping their heart beating and oxygen circulating through their blood. When brain stem function is permanently lost, the person will be confirmed dead.
Brain dead is the irreversible end of all brain activity. Some of the criteria would be the person being unresponsive. There will be no facial sensation or response. There would be no response to light directly in their eyes.
Example: Mr Chua is dead, can he still sneeze?
4. Someone in a persistent vegetative state can show signs of wakefulness (they may open their eyes, for example) but have no response to their surroundings.
However, the important difference between PVS and brain death is that a patient with PVS still has a functioning brain stem, therefore:
Some form of consciousness may exist in someone in a PVS.
A person in a PVS can still breathe unaided.
A person in a PVS has a slim chance of recovering because the core functions of the brain stem are often unaffected, whereas a person with brain death has no chance of recovery as the body cannot survive without artificial support.
Example: Mr Chua has been in a coma for 3 years, yet he is still breathing and his core functions are still functioning, is he dead or in a vegetative state?
5. There is no strict way of defining death. Some of the other ethical issues would be concerning the certainty of diagnosis and about the medical steps that may be taken after death is pronounced. The definition of death is a moral issue and that confronting it as such vindicates the higher-brain approach.
For example, in the past, people were declared dead if organs were missing. However, due to technological advancements, organ transplants and blood transfusions have been made possible and have allowed people in near-death situations to survive. This has led to the ethical implication of people surviving when they should have been dead instead.
Human organs have been made possible to replace with other animal organs such as pigs, who have similar organs as people.
Example: Mr Chua’s organs are missing, is he dead?
By: Carissa, Chang Han, River, Crystal and Desiree :)
Sunday 13 January 2013
Definition of Life
1. What is the definition (legally and medically) of death?
Medical death is the cessation of all functions of the entire brain.
Legal death is a legal pronouncement by a qualified person that further medical care is not appropriate and that a patient should be considered dead under the law
2. How has the definition of death changed through the years and how does it vary across cultures?
If a person fell unconscious or was found so , the physician would feel for the pulse and listen for breathing , listen for breathing , hold a mirror to test for condensation in order to determine whether the individual is dead . In 1740 , there was a theory that putrefaction is the only sure sign of death . However , people still wanted to find more ways to define death so they developed stethoscopes to detect heartbeat and confirm whether the person is dead . In 2000 , the EKG was invented and it is used to detect and measure cardiac functioning.
Cultures - Although the final outcome of death is the same for all humans, cultures vary in how they conceptualize death and what happens when a person dies. In some cultures, death is conceived to involve different conditions, including sleep, illness, and reaching a certain age. In other cultures, death is said to occur only when there is a total cessation of life. Mostly what differs between culture is what happens after you die . Do you get reborn or do you shed your skin and continue life like that . In some cultures , they make distinctions between an acceptable death and a good death . A good death is where you simply wait till your body ceases functioning . While a good death is adjusting to social standards and doing meaningful things before you die . Some South Pacific cultures believe that life, as is generally construed, departs the body of a person in different situations, such as when one is ill or asleep. Thus conceptualized, people can be said to "die" several times before the final death. Where as another culture believes that life ends at the edge of 40 and even if you live beyond that , you are still considered dead .
3. What are some criteria the medical community uses to determine if one is “brain dead”?
Criteria for brain death:
No response to pain, no cranial nerve reflexes(e.g. pupillary response, oculocephalic reflex, corneal reflex, no response to the caloric reflex test and no spontaneous respirations.
4. Describe some difference between “persistent vegetative state” and “brain death”
- A brain-dead patient is unconscious, has lost the capacity to breathe and requires mechanical respiration, where as a person in persistent vegetative state is able to breathe by him/herself.
- For brain dead people with full supportive treatment, his/her heart will soon stop, usually only after a few days. Whereas if given adequate treatment persons in a vegetative state can survive for years.
5. What are some of the ethical implications of these definitions of death? Provide some real-life examples
The ethical question is whether a new, brain-oriented definition of death would lead to abandonment of patients who might have responded to continued medical care.
Under the clinical standard, death will be pronounced in cases in which there is an irreversible loss of brain functions while respiration is artificially supplied. However, with what assurance can a qualified person state that the relevant organs will not resume functioning in a person diagnosed to have lost certain vital functions?
There was a family feud over ending life support for Terri Schiavo in the United States in 2005. Another example would be a British couple's fight to save their severely handicapped baby Charlotte Wyatt in 2003, when doctors wanted to give up on her.
From : Shaun , Mason , Jia Qi , Kai En and Owen
Thursday 10 January 2013
Definition of Life (the 5 questions) by Farrell, Justin, Jemima, Dean, Wai Kit
1. What is the definition (legally and medically) of death?
Legal death is a legal pronouncement by a qualified person that further medical care is not appropriate and that a patient should be considered dead under the law.
Death is the permanent cessation of all biological functions that sustain a living organism. For example, brain death, as practiced in medical science, defines death as a point in time at which brain activity ceases.
2. How has the definition of death changed through the years and how does it vary across cultures?
Death was once defined as the cessation of a heartbeat and or breathing, but with CPR and defibrillation, these are now unreliable as heartbeat and breathing can sometimes be restarted. In the past, death also meant the loss of essential organs, but with advances in science, it is possible to sustain life even if the person has to heart, lungs or other organs.
Definitions of death have been greatly affected by religion, where it is treated as an interlude to another stage of existence. The concept of resurrection (Abrahmic religions), reincarnation (Dharmic religions), consciousness ceasing to exist (atheism) or and afterlife, commonly involving a "heaven" and "hell"
3. What are some criteria the medical community uses to determine if one is “brain dead”?
Brain Death is the absence of clinical brain function when the proximate cause is known and demonstrably irreversible.
Criteria includes:
a) Must be in Coma or unresponsive--no pain reflex
b)Absence of Brain stem reflexes eg: no response to light, no blinking, no coughing, no gagging reflex, cannot focus on one spot
c) No breathing--Apnea
4. Describe some difference between “persistent vegetative state” and “brain death”
Persistent Vegetative State means that the brain has at least a single function left alive, and can at least hold one reflex based on the criteria above. Brain death means there is completely no reflexes at all.
5. What are some of the ethical implications of these definitions of death? Provide some real-life examples
In the past, as death was inevitable when internal organs were missing, it was often that people of such victims would be proclaimed dead. However, with the recent advancements for blood transfusion and organ transplants, it allows for patients to survive. With this concept of 'escaping death', certain religions object to the use of blood transfusions due to the idea of impurity. This ethical issue has to do with the idea of either saving someone or letting them die in the name of the religion.
One current law implemented is that families/guardians have control over the life and death of a person within a persistent vegetative state. To put them out of pain, or to allow them to survive? This ethical issue deals with the concept of human suffering. Unlike normal death, a persistent vegetative state allows the body to function but not as fully as before. Families can decide to medically stop their heart, but the moral dilemma is of the "cruelty" and "immorality" behind it.
A current practice now is to use the bodies of those who are proclaimed deceased (usually brain dead) for medical practices. In several medical schools, bodies are used to practice surgery especially for the juniors. Families (or the deceased when he was alive) would have signed the documents, but it leads to the ethical issue of how the body is disposed/used after death. Many people view this as a defilement to the corpse, but for the scientific and medical advancement purposes, is it right to perform surgery on the dead?
Tuesday 8 January 2013
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