Examine the statement from the American College of Pediatricians on when human life begins. We looked at the concept of "organism" and why it was relevant.  Why the Church is opposed to "direct" but not "Indirect" abortion.  Look at "In vitro fertilization", both homologous and heterologous, what were the moral concerns related to these and finally we looked at some of the issues related to "ectopic" pregnancies.

 

Sulmasy, Daniel, O.F.M., M.D., Ph.D.. THE REBIRTH OF THE CLINIC: AN INTRODUCTION TO THE SPIRITUALITY OF HEALTH CARE. Georgetown University Press: Washington, 2007. 

Ashley, Benedict, O.P. and O'Rourke, Kevin, O.P. ETHICS OF HEALTH CARE. Georgetown University Press: Washington, 2002.

Human life begin

Life Begins at Fertilization with the Embryo's Conception. "Development of the embryo begins at Stage 1 when a sperm fertilizes an oocyte and together they form a zygote." "Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (conception).

 

When Human Life Begins

 

- The predominance of human biological research confirms that human life begins at conception fertilization.  At fertilization, the human being emerges as a whole, genetically distinct, individuated zygotic living human organism, a member of the species Homo sapiens, needing only the proper environment in order to grow and develop. The difference between the individual in its adult stage and in its zygotic stage is one of form, not nature. This statement focuses on the scientific evidence of when an individual human life begins.

- In the last century, and particularly in the last decades, much more detailed observation has been made of the first 24 hours of the life of a human being.  During this time the cell membranes of a sperm and ovum fuse and the first cell division occurs.  When during this 24 hours does, a new human life begin? Embryologists are less united on this question.  This Statement aims to clarify this issue.

During the first 24 hours, once the sperm and egg bind to each other, the membranes of these two cells fuse, creating in less than a second a single hybrid cell: the zygote, or one-cell embryo. To protect his or her bodily integrity, within minutes the zygote initiates changes in its ionic composition, releasing zinc in a spark that induces "egg activation," first modifying the surrounding zona pellucida blocking further sperm binding to the cell surface. Cooperation between sperm and egg components to achieve replication of DNA, cell division, and growth occurs as maternally and paternally derived factors in the zygote begin interacting with and chemically modifying each other to initiate the final round of meiotic division in the maternally derived nucleus to enable DNA replication.

 

Some embryologists consider fertilization a day-long process and regard the beginning of human life as occurring near the end of this process at syngamy,^1,18,21 whereas others consider the time of cell membrane fusion when the embryo gives evidence of being a different kind of cell than either oocyte or sperm, to be the beginning of a new human life, since within minutes the new embryo acts to prevent the merger of another sperm with itself and starts the business of self-replication.  The single-celled embryo is a very different kind of cell than that of sperm or oocyte, and contains a unique genome that will determine most future bodily features and functions of his or her lifetime.

An organism is defined as "

(1) a complex structure of interdependent and subordinate elements whose relations and properties are largely determined by their function in the whole

(2) an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent: a living being.

The American College of Pediatricians concurs with the body of scientific evidence that corroborates that a unique human life starts when the sperm and egg bind to each other in a process of fusion of their respective membranes and a single hybrid cell called a zygote, or one-cell embryo, is created.

As physicians dedicated both to scientific truth and to the Hippocratic tradition, the College values all human lives equally from the moment of conception (fertilization) until natural death. Consistent with its mission to "enable all children to reach their optimal physical and emotional health and well-being," the College, therefore, opposes active measures²³ that would prematurely end the life of any child at any stage of development from conception to natural death.

 

human being begin

Getting a handle on just a few basic human embryological terms accurately can considerably clarify the drastic difference between the "scientific" myths that are currently circulating, and the actual objective scientific facts. This would include such basic terms as: "gametogenesis," "oogenesis," "spermatogenesis," "fertilization," "zygote," "embryo," and "blastocyst." Only brief scientific descriptions will be given here for these terms. Further, more complicated, details can be obtained by investigating any well-established human embryology textbook in the library, such as some of those referenced below. Please note that the scientific facts presented here are not simply a matter of my own opinion. They are direct quotes and references from some of the most highly respected human embryology textbooks, and represent a consensus of human embryologists internationally.

 

Basic human embryological facts

To begin with, scientifically something very radical occurs between the processes of gametogenesis and fertilization the change from a simple part of one human being ) and a simple part of another human being , which simply possess "human life", to a new, genetically unique, newly existing, individual, whole living human being (a single-cell embryonic human zygote). That is, upon fertilization, parts of human beings have actually been transformed into something very different from what they were before; they have been changed into a single, whole human being. During the process of fertilization, the sperm and the oocyte cease to exist as such, and a new human being is produced.

 

To accurately see why a sperm or an oocyte are considered as only possessing human life, and not as living human beings themselves, one needs to look at the basic scientific facts involved in the processes of gametogenesis and of fertilization. It may help to keep in mind that the products of gametogenesis and fertilization are very different. The products of gametogenesis are mature sex gametes with only 23 instead of 46 chromosomes. The product of fertilization is a living human being with 46 chromosomes. Gametogenesis refers to the maturation of germ cells, resulting in gametes. Fertilization refers to the initiation of a new human being.

1) Gametogenesis

As the human embryologist Larsen² states it, gametogenesis is the process that converts primordial germ cells (primitive sex cells) into mature sex gametes in the male (spermatozoa, or sperms), and in the female (definitive oocytes). The timing of gametogenesis is different in males and in females. The later stages of spermatogenesis in males occur at puberty, and continue throughout adult life. The process involves the production of spermatogonia from the primitive germ cells, which in turn become primary spermatocytes, and finally spermatids or mature spermatozoa (sperms). These mature sperms will have only half of the number of their original chromosomes i.e., the number of chromosomes has been cut from 46 to 23, and therefore they are ready to take part in fertilization.

Oogenesis begins in the female during fetal life. The total number of primary oocytes about 7 million is produced in the female fetus  ovaries by 5 months of gestation in the mothers uterus. By birth, only about 700,000 - 2 million remain. By puberty, only about 400,000 remain. The process includes several stages of maturation the production of oogonia from primitive germ cells, which in turn become primary oocytes, which become definitive oocytes only at puberty. This definitive oocyte is what is released each month during the females menstrual period, but it still has 46 chromosomes. In fact, it does not reduce its number of chromosomes until and unless it is fertilized by the sperm, during which process the definitive oocyte becomes a secondary oocyte with only 23 chromosomes.

"Oogenesis is the production and maturation of oocytes, i.e.; the female gametes derived from oogonia. Oogonia (derived from primordial germ cells) multiply by mitosis and become primary oocytes. The number of oogonia increases to nearly seven million by the middle of prenatal life, after which it diminishes to about two million at birth. From these, several thousand oocytes are derived, several hundred of which mature and are liberated (ovulated) during a reproductive period of some thirty years. Prophase of meiosis 1 begins during fetal life but ceases at the diplotene state, which persists during childhood. After puberty, meiosis 1 is resumed and a secondary oocyte  is formed, together with polar body 1, which can be regarded as an oocyte having a reduced share of cytoplasm. The secondary oocyte is a female gamete in which the first meiotic division is completed and the second has begun. From oogonium to secondary oocyte takes from about 12 to 50 years to be completed. Meiosis 2 is terminated after rupture of the follicle (ovulation) but only if a spermatozoon penetrates. The term ovum implies that polar body 2 has been given off, which event is usually delayed until the oocyte has been penetrated by a spermatozoon (i.e., has been fertilized). Hence a human ovum does not [really] exist. Moreover the term has been used for such disparate structures as an oocyte and a three-week embryo, and therefore should be discarded, as a fortiori should egg

"Gametogenesis is the production of [gametes], i.e., spermatozoa and oocytes. These cells are produced in the gonads, i.e., the testes and ovaries respectively. During the differentiation of gametes, diploid cells (those with a double set of chromosomes, as found in somatic cells [46 chromosomes]) are termed primary, and haploid cells (those with a single set of chromosomes [23 chromosomes]) are called secondary. The reduction of chromosomal number from 46 (the diploid number or 2n) to 23 (the haploid number or n) is accomplished by a cellular division termed meiosis. Spermatogenesis, the production of spermatozoa, continues from immediately after puberty until old age. It takes place in the testis, which is also an endocrine gland, the interstitial cells of which secrete testosterone. Previous to puberty, spermatogonia in the simiferous tubules of the testis remain relatively inactive. After puberty, under stimulation from the interstitial cells, spermatogonia proliferate and some become primary spermatocytes. When these undergo their first maturation division (meiosis 1), they become secondary spermatocytes. The second maturation division (meiosis 2) results in spermatids, which become converted into spermatozoa.

2) Fertilization

Now that we have looked at the formation of the mature haploid sex gametes, the next important process to consider is fertilization. O Rahilly defines fertilization as:

"... the procession of events that begins when a spermatozoon makes contact with a secondary oocyte or its investments, and ends with the intermingling of maternal and paternal chromosomes at metaphase of the first mitotic division of the zygote. The zygote is characteristic of the last phase of fertilization and is identified by the first cleavage spindle. It is a unicellular embryo."⁹ (Emphasis added.)

The fusion of the sperm (with 23 chromosomes) and the oocyte (with 23 chromosomes) at fertilization results in a live human being, a single-cell human zygote, with 46 chromosomes the number of chromosomes characteristic of an individual member of the human species. Quoting Moore:

"Zygote: This cell results from the union of an oocyte and a sperm. A zygote is the beginning of a new human being (i.e., an embryo). The expression fertilized ovum refers to a secondary oocyte that is impregnated by a sperm; when fertilization is complete, the oocyte becomes a zygote.

 

Step-by-step explanation

Human life begin

Life Begins at Fertilization with the Embryo's Conception. "Development of the embryo begins at Stage 1 when a sperm fertilizes an oocyte and together they form a zygote." "Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (conception).

 

When Human Life Begins

 

- The predominance of human biological research confirms that human life begins at conception fertilization.  At fertilization, the human being emerges as a whole, genetically distinct, individuated zygotic living human organism, a member of the species Homo sapiens, needing only the proper environment in order to grow and develop. The difference between the individual in its adult stage and in its zygotic stage is one of form, not nature. This statement focuses on the scientific evidence of when an individual human life begins.

- In the last century, and particularly in the last decades, much more detailed observation has been made of the first 24 hours of the life of a human being.  During this time the cell membranes of a sperm and ovum fuse and the first cell division occurs.  When during this 24 hours does, a new human life begin? Embryologists are less united on this question.  This Statement aims to clarify this issue.

During the first 24 hours, once the sperm and egg bind to each other, the membranes of these two cells fuse, creating in less than a second a single hybrid cell: the zygote, or one-cell embryo. To protect his or her bodily integrity, within minutes the zygote initiates changes in its ionic composition, releasing zinc in a spark that induces "egg activation," first modifying the surrounding zona pellucida blocking further sperm binding to the cell surface. Cooperation between sperm and egg components to achieve replication of DNA, cell division, and growth occurs as maternally and paternally derived factors in the zygote begin interacting with and chemically modifying each other to initiate the final round of meiotic division in the maternally derived nucleus to enable DNA replication.

 

Some embryologists consider fertilization a day-long process and regard the beginning of human life as occurring near the end of this process at syngamy,^1,18,21 whereas others consider the time of cell membrane fusion when the embryo gives evidence of being a different kind of cell than either oocyte or sperm, to be the beginning of a new human life, since within minutes the new embryo acts to prevent the merger of another sperm with itself and starts the business of self-replication.  The single-celled embryo is a very different kind of cell than that of sperm or oocyte, and contains a unique genome that will determine most future bodily features and functions of his or her lifetime.

An organism is defined as "

(1) a complex structure of interdependent and subordinate elements whose relations and properties are largely determined by their function in the whole

(2) an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent: a living being.

The American College of Pediatricians concurs with the body of scientific evidence that corroborates that a unique human life starts when the sperm and egg bind to each other in a process of fusion of their respective membranes and a single hybrid cell called a zygote, or one-cell embryo, is created.

As physicians dedicated both to scientific truth and to the Hippocratic tradition, the College values all human lives equally from the moment of conception (fertilization) until natural death. Consistent with its mission to "enable all children to reach their optimal physical and emotional health and well-being," the College, therefore, opposes active measures²³ that would prematurely end the life of any child at any stage of development from conception to natural death.

 

human being begin

Getting a handle on just a few basic human embryological terms accurately can considerably clarify the drastic difference between the "scientific" myths that are currently circulating, and the actual objective scientific facts. This would include such basic terms as: "gametogenesis," "oogenesis," "spermatogenesis," "fertilization," "zygote," "embryo," and "blastocyst." Only brief scientific descriptions will be given here for these terms. Further, more complicated, details can be obtained by investigating any well-established human embryology textbook in the library, such as some of those referenced below. Please note that the scientific facts presented here are not simply a matter of my own opinion. They are direct quotes and references from some of the most highly respected human embryology textbooks, and represent a consensus of human embryologists internationally.

 

Basic human embryological facts

To begin with, scientifically something very radical occurs between the processes of gametogenesis and fertilization the change from a simple part of one human being ) and a simple part of another human being , which simply possess "human life", to a new, genetically unique, newly existing, individual, whole living human being (a single-cell embryonic human zygote). That is, upon fertilization, parts of human beings have actually been transformed into something very different from what they were before; they have been changed into a single, whole human being. During the process of fertilization, the sperm and the oocyte cease to exist as such, and a new human being is produced.

 

To accurately see why a sperm or an oocyte are considered as only possessing human life, and not as living human beings themselves, one needs to look at the basic scientific facts involved in the processes of gametogenesis and of fertilization. It may help to keep in mind that the products of gametogenesis and fertilization are very different. The products of gametogenesis are mature sex gametes with only 23 instead of 46 chromosomes. The product of fertilization is a living human being with 46 chromosomes. Gametogenesis refers to the maturation of germ cells, resulting in gametes. Fertilization refers to the initiation of a new human being.

1) Gametogenesis

As the human embryologist Larsen² states it, gametogenesis is the process that converts primordial germ cells (primitive sex cells) into mature sex gametes in the male (spermatozoa, or sperms), and in the female (definitive oocytes). The timing of gametogenesis is different in males and in females. The later stages of spermatogenesis in males occur at puberty, and continue throughout adult life. The process involves the production of spermatogonia from the primitive germ cells, which in turn become primary spermatocytes, and finally spermatids or mature spermatozoa (sperms). These mature sperms will have only half of the number of their original chromosomes i.e., the number of chromosomes has been cut from 46 to 23, and therefore they are ready to take part in fertilization.

Oogenesis begins in the female during fetal life. The total number of primary oocytes about 7 million is produced in the female fetus  ovaries by 5 months of gestation in the mothers uterus. By birth, only about 700,000 - 2 million remain. By puberty, only about 400,000 remain. The process includes several stages of maturation the production of oogonia from primitive germ cells, which in turn become primary oocytes, which become definitive oocytes only at puberty. This definitive oocyte is what is released each month during the females menstrual period, but it still has 46 chromosomes. In fact, it does not reduce its number of chromosomes until and unless it is fertilized by the sperm, during which process the definitive oocyte becomes a secondary oocyte with only 23 chromosomes.

"Oogenesis is the production and maturation of oocytes, i.e.; the female gametes derived from oogonia. Oogonia (derived from primordial germ cells) multiply by mitosis and become primary oocytes. The number of oogonia increases to nearly seven million by the middle of prenatal life, after which it diminishes to about two million at birth. From these, several thousand oocytes are derived, several hundred of which mature and are liberated (ovulated) during a reproductive period of some thirty years. Prophase of meiosis 1 begins during fetal life but ceases at the diplotene state, which persists during childhood. After puberty, meiosis 1 is resumed and a secondary oocyte  is formed, together with polar body 1, which can be regarded as an oocyte having a reduced share of cytoplasm. The secondary oocyte is a female gamete in which the first meiotic division is completed and the second has begun. From oogonium to secondary oocyte takes from about 12 to 50 years to be completed. Meiosis 2 is terminated after rupture of the follicle (ovulation) but only if a spermatozoon penetrates. The term ovum implies that polar body 2 has been given off, which event is usually delayed until the oocyte has been penetrated by a spermatozoon (i.e., has been fertilized). Hence a human ovum does not [really] exist. Moreover the term has been used for such disparate structures as an oocyte and a three-week embryo, and therefore should be discarded, as a fortiori should egg

"Gametogenesis is the production of [gametes], i.e., spermatozoa and oocytes. These cells are produced in the gonads, i.e., the testes and ovaries respectively. During the differentiation of gametes, diploid cells (those with a double set of chromosomes, as found in somatic cells [46 chromosomes]) are termed primary, and haploid cells (those with a single set of chromosomes [23 chromosomes]) are called secondary. The reduction of chromosomal number from 46 (the diploid number or 2n) to 23 (the haploid number or n) is accomplished by a cellular division termed meiosis. Spermatogenesis, the production of spermatozoa, continues from immediately after puberty until old age. It takes place in the testis, which is also an endocrine gland, the interstitial cells of which secrete testosterone. Previous to puberty, spermatogonia in the simiferous tubules of the testis remain relatively inactive. After puberty, under stimulation from the interstitial cells, spermatogonia proliferate and some become primary spermatocytes. When these undergo their first maturation division (meiosis 1), they become secondary spermatocytes. The second maturation division (meiosis 2) results in spermatids, which become converted into spermatozoa.

2) Fertilization

Now that we have looked at the formation of the mature haploid sex gametes, the next important process to consider is fertilization. O Rahilly defines fertilization as:

"... the procession of events that begins when a spermatozoon makes contact with a secondary oocyte or its investments, and ends with the intermingling of maternal and paternal chromosomes at metaphase of the first mitotic division of the zygote. The zygote is characteristic of the last phase of fertilization and is identified by the first cleavage spindle. It is a unicellular embryo."⁹ (Emphasis added.)

The fusion of the sperm (with 23 chromosomes) and the oocyte (with 23 chromosomes) at fertilization results in a live human being, a single-cell human zygote, with 46 chromosomes the number of chromosomes characteristic of an individual member of the human species. Quoting Moore:

"Zygote: This cell results from the union of an oocyte and a sperm. A zygote is the beginning of a new human being (i.e., an embryo). The expression fertilized ovum refers to a secondary oocyte that is impregnated by a sperm; when fertilization is complete, the oocyte becomes a zygote.

 

Life - when does it begin?

Human Life comes into existence in just a fraction of an instant. You have a human egg and a human sperm and their sole purpose in life is to meet each other and fuse, to create a one cell human being. Within this single cell there is an elaborate and complete plan for development.

- "An individual human life begins at conception when a sperm cell from the father fuses with an egg cell from the mother, to form a new cell, the zygote, the first embryonic stage. The zygote grows and divides into two daughter cells, each of which grows and divides into two grand-daughter cells, and this cell growth/division process continues on, over and over again.  The zygote is the start of a biological continuum that automatically grows and develops, passing gradually and sequentially through the stages we call fetus, baby, child, adult, old person and ending eventually in death. The full genetic instructions to guide the development of the continuum, in interaction with its environment, are present in the zygote. Every stage along the continuum is biologically human and each point along the continuum has the full human properties appropriate to that point."