REPRODUCTION
Reproduction is the biological process by which new individual organisms are produced. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. The known methods of reproduction are broadly grouped into two main types: s
exual and asexual.
In asexual reproduction, an individual can reproduce without involvement with another individual of that species. The division of a bacterial cell into two daughter cells is an example of asexual reproduction. Asexual reproduction is not, however, limited to single-celled organisms. Most plants have the ability to reproduce asexually.
Human reproduction is any form of sexual reproduction res
ulting in the conception of a child, typically involving sexual intercourse between a man and a woman. During sexual intercourse, the interaction between the male reproductive system and the female reproductive system results in fertilization of the woman's ovum by the man's sperm, which after a gestation period is followed by childbirth. The fertilization of the ovum may nowadays be achieved by artificial insemination methods, which do not involve sexual intercourse.
The human male
The ma
le reproductive is made up of a pp system contains two main divisi
ons: the penis, and the testes, the latter of which is where sperm are produced. In humans, both of these organ
s are outside the abdominal cavity. Having the testes outside the abdomen best facilitates temperature regulation of the sperm, which require specific temperatures to survive.
Sperm are smaller than the female ovum, and live approximately 2 weeks after production, requiring males to produce them continuously from the time of sexual maturity until death.
A sperm cell is motile and swims via chemotaxis, using its flagellum to propel i
tself towards the ovum.
The human female
The female reproductive system likewise contains two main divisions
: the vagina and uterus, which act as the receptacle for the semen, and the ovaries, which produce the female's ova. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the fallopian tube into the uterus.
If, in this transit, it meets with Spermatozoon, the sperm penetrate and merge with the egg, fertilizing it. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then implants itself in the wall of the uterus, where it begins the processes of embryogenesis and morphogenesis. When developed enough to survive outside the womb, the cervix dilates and contractions of the uterus propel the foetus through the birth canal, which is the vagina.
The ova, which are the female sex cells, are much larger than the spermatozoon and are normally formed with in the ovaries of the fetus before its birth. They are mostly fixed in location with in the ovary until their transit to the uterus, and contain nutrients for the later zygote and embry
o. Over a regular interval, in response to hormonal signals, a process of oogenesis matures one ovum which is released and sent down the Fallopian tube. If not fertilized, this egg is flushed out of the system through menstruation.
Process
Human reproduction is a long process, starting with sexual intercourse, followed by nine months of pregnancy before childbirth. Many years of parental care is required in order to finish with a mature human being.
Sexual intercourse
Human reproduction takes place as internal fertilization by sexual intercourse. During this process, the erect penis of the male is inserted into the female's vagina until the male ejaculates semen, which contains sperm, into the female's vagina. The sperm then travels through the vagina and cervix into the uterus or fallopian tubes for fertilization of th
e ovum. Upon successful fertilization and implantation, gestation of the fetus then occurs within the female's uterus, called pregnancy. This process is also known as "mating" or "having sex".
Pregnancy
Pregnancy is the period of time during which the fetus develops, dividing via mitosis inside the female. During this time, the fetus receives all
of its nutrition and oxygenated blood from the female, filtered through the placenta, which is attached to the fetus' abdomen via an umbilical cord. This drain of nutrients can be quite taxing on the female, who is required to ingest slightly higher l
evels of calories. In addition, certain vitamins and other nutrients are required in greater quantities than normal, often creating abnormal eating habits. Gestation is 40 weeks in humans.
Birth
Once the fetus is sufficiently developed, chemical signals start the process of birth, which begins with the fetus squeezing through the vagina, and eventually out of the female. The newborn, which
is called an infant in humans, should typically begin respiration on its own shortly after birth. Not long after, the placenta is passed as well. The end of the umbilical cord attached to the child's abdomen eventually falls off on its own.The mid-wife or nurse assisting the birth will usually detach the mother from the baby using a clamp, then cutting it off.
Parental care
Human's babies and children are nearly helpless and require high levels of parental care for many years. One important type of parental care is the use of the mammary glands in the female breasts to nurse the baby.
exual and asexual.In asexual reproduction, an individual can reproduce without involvement with another individual of that species. The division of a bacterial cell into two daughter cells is an example of asexual reproduction. Asexual reproduction is not, however, limited to single-celled organisms. Most plants have the ability to reproduce asexually.
Human reproduction is any form of sexual reproduction res
ulting in the conception of a child, typically involving sexual intercourse between a man and a woman. During sexual intercourse, the interaction between the male reproductive system and the female reproductive system results in fertilization of the woman's ovum by the man's sperm, which after a gestation period is followed by childbirth. The fertilization of the ovum may nowadays be achieved by artificial insemination methods, which do not involve sexual intercourse.The human male
The ma
le reproductive is made up of a pp system contains two main divisions: the penis, and the testes, the latter of which is where sperm are produced. In humans, both of these organ
s are outside the abdominal cavity. Having the testes outside the abdomen best facilitates temperature regulation of the sperm, which require specific temperatures to survive.
Sperm are smaller than the female ovum, and live approximately 2 weeks after production, requiring males to produce them continuously from the time of sexual maturity until death.
A sperm cell is motile and swims via chemotaxis, using its flagellum to propel i
tself towards the ovum.
The human female
The female reproductive system likewise contains two main divisions
: the vagina and uterus, which act as the receptacle for the semen, and the ovaries, which produce the female's ova. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the fallopian tube into the uterus.
If, in this transit, it meets with Spermatozoon, the sperm penetrate and merge with the egg, fertilizing it. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then implants itself in the wall of the uterus, where it begins the processes of embryogenesis and morphogenesis. When developed enough to survive outside the womb, the cervix dilates and contractions of the uterus propel the foetus through the birth canal, which is the vagina.
The ova, which are the female sex cells, are much larger than the spermatozoon and are normally formed with in the ovaries of the fetus before its birth. They are mostly fixed in location with in the ovary until their transit to the uterus, and contain nutrients for the later zygote and embry
o. Over a regular interval, in response to hormonal signals, a process of oogenesis matures one ovum which is released and sent down the Fallopian tube. If not fertilized, this egg is flushed out of the system through menstruation.
Process
Human reproduction is a long process, starting with sexual intercourse, followed by nine months of pregnancy before childbirth. Many years of parental care is required in order to finish with a mature human being.
Sexual intercourse
Human reproduction takes place as internal fertilization by sexual intercourse. During this process, the erect penis of the male is inserted into the female's vagina until the male ejaculates semen, which contains sperm, into the female's vagina. The sperm then travels through the vagina and cervix into the uterus or fallopian tubes for fertilization of th
e ovum. Upon successful fertilization and implantation, gestation of the fetus then occurs within the female's uterus, called pregnancy. This process is also known as "mating" or "having sex".
Pregnancy
Pregnancy is the period of time during which the fetus develops, dividing via mitosis inside the female. During this time, the fetus receives all
of its nutrition and oxygenated blood from the female, filtered through the placenta, which is attached to the fetus' abdomen via an umbilical cord. This drain of nutrients can be quite taxing on the female, who is required to ingest slightly higher l
evels of calories. In addition, certain vitamins and other nutrients are required in greater quantities than normal, often creating abnormal eating habits. Gestation is 40 weeks in humans.
Birth
Once the fetus is sufficiently developed, chemical signals start the process of birth, which begins with the fetus squeezing through the vagina, and eventually out of the female. The newborn, which
is called an infant in humans, should typically begin respiration on its own shortly after birth. Not long after, the placenta is passed as well. The end of the umbilical cord attached to the child's abdomen eventually falls off on its own.The mid-wife or nurse assisting the birth will usually detach the mother from the baby using a clamp, then cutting it off.Parental care
Human's babies and children are nearly helpless and require high levels of parental care for many years. One important type of parental care is the use of the mammary glands in the female breasts to nurse the baby.
Rabu, 18 November 2009
JANTUNG
Teman-teman, ayo kita lakukan penelitian kecil denganku! Letakan tanganmu di dadamu. Apa kamu merasakan sesuatu yang berdetak? Ya, itu adalah jantungmu. Kita tau bahwa jantung memompa untuk memproduksi darah segar untuk semua jaringan tubuh. Tetapi, taukah kamu bagaimana jantung memompa darah dan menyalurkannya ke seluruh jaringan tubuh?
Seperti yang kita bicarakan, jantung menyemprotkan darah yang kaya oksigen dengan tekanan tinggi dari ruang bilik yang menuju jantung, serambi kiri lalu ke pembuluh nadi terbesar yaitu aorta. Pembuluh nadi terkecil bercabang dari aorta, menuju ke segala bagian tubuh. Arteri ini bercabang menjadi yang lebih kecil lagi, yang disebut arterioles.
Pembulu kapiler punya dinding yang sangat tipis sehingga oksigen dan nutrisi dapat larut dari darah yang terdifusi ke cairan yang disebut cairan interstitial yang mengisi sela-sela antar sel dari suatu jaringan atau organ. Oksigen dan nutrisi yang larut masuk ke dalam sel dari cairan interstitial dengan difusi melewati membrane sel. Dengan cara ini, darah menyebarkan nutrisi dan memindahkan sisa metabolisme tanpa meninggalkan pembulu kapiler.
Setelah mengedarkan oksigen ke jaringan, darah yang kurang oksigen [terdeoksigenasi] dalam kapiler, lalu mulai kembali ke jantung.
HEART
Guys, do a little research with me! Put the palm of your chest. Do you feel something beating? Yes. It is your heart. We have known that heart pumps to produce fresh blood for all body tissues. However, do you know how heart pumps blood and circulate it to all body tissues.
As we talk, the heart ejects oxygen rich blood under high pressure out of the heart’s main pumping chamber, the left ventricle, through the largest artery, the aorta.
Smaller arteries in turn branch out into even smaller arteries, called arterioles.
Capillaries have extremely thin walls that permit dissolved oxygen and nutrients from the blood to diffuse across to a fluid, known as interstitial fluid that fills the gaps between the cells of tissues or organs. The dissolved oxygen and nutrients then enter the cells from the interstitial fluid by diffusion across the cell membranes. In this way, the blood delivers nutrients and removes wastes without leaving the capillary tube.
After delivering oxygen to tissues, the deoxygenated blood in capillaries then starts the return trip to the heart.
Senin, 16 November 2009
REMEDIAL TEST..........!!
A. CHANGE INTO THE PASSIVE VOICE:
1. Mr T tells us to close our notebooks
-We are told to close our notebooks
2. People speak English all over the world
-English is spoken all over the world
3. Did anyone ask any questions about me?
- Were any questions asked about me?
4. We have been waiting for him all day long
-He has been being waited all day long
5. Mr Jack has invited you to lunch tomorrow
-You have been invited to lunch tomorrow
6. The students did not do the English test easily
-The English test was not done easily
7. You must check the answer before you give it back
-The answer must be checked before you give it back
8. We are doing the passive test in the Multi Media Room
- The passive test is being done in the Multi Media Room
9. Would you join the remedial test if you got bad mark again?
-Would the remedial test be joined if you got bad mark again
10. The white board has been cleaned by you
-You have cleaned the whiteboard11. The interview will be done in this room by us
-We will do the interview in this room
12. English was being studied diligently by them last night
-They were studying English diligently last night13. This test must be finished in 45 minutes by the students
-The students must finish the test in 45 minutes14. We have been being taught math by Mr Sus for three years
-Mr Sus has been teaching us math for three years
15. Will the coming UAN test be being faced by you in the month of April ?
-Will you be facing the UAN test in the month of April ?
16. Mr Fajar is showing us his new blog
-We are being shown his new blog
-His new blog is being shown to us17. They will be asking her several questions
-She will be being asked several questions
-Several questions will be being asked to her18. Mrs Nanik has been reading them another story
-They have been being read another story
-Another story has been being read to them19. Does he tell you the new law of Archimedes ?
-Are you told the new law of Archimedes?
-Is the new law of Archimedes told to you?
20. We should have given him our new projects before he came her
-He should have been given our new project before he came here
-Our new project should have been given to him before he came here
1. Mr T tells us to close our notebooks
-We are told to close our notebooks
2. People speak English all over the world
-English is spoken all over the world
3. Did anyone ask any questions about me?
- Were any questions asked about me?
4. We have been waiting for him all day long
-He has been being waited all day long
5. Mr Jack has invited you to lunch tomorrow
-You have been invited to lunch tomorrow
6. The students did not do the English test easily
-The English test was not done easily
7. You must check the answer before you give it back
-The answer must be checked before you give it back
8. We are doing the passive test in the Multi Media Room
- The passive test is being done in the Multi Media Room
9. Would you join the remedial test if you got bad mark again?
-Would the remedial test be joined if you got bad mark again
B. CHANGE INTO THE ACTIVE VOICE:
10. The white board has been cleaned by you
-You have cleaned the whiteboard11. The interview will be done in this room by us
-We will do the interview in this room
12. English was being studied diligently by them last night
-They were studying English diligently last night13. This test must be finished in 45 minutes by the students
-The students must finish the test in 45 minutes14. We have been being taught math by Mr Sus for three years
-Mr Sus has been teaching us math for three years
15. Will the coming UAN test be being faced by you in the month of April ?
-Will you be facing the UAN test in the month of April ?
C. CHANGE INTO THE PASSIVE VOICE (two objects) :
16. Mr Fajar is showing us his new blog
-We are being shown his new blog
-His new blog is being shown to us17. They will be asking her several questions
-She will be being asked several questions
-Several questions will be being asked to her18. Mrs Nanik has been reading them another story
-They have been being read another story
-Another story has been being read to them19. Does he tell you the new law of Archimedes ?
-Are you told the new law of Archimedes?
-Is the new law of Archimedes told to you?
20. We should have given him our new projects before he came her
-He should have been given our new project before he came here
-Our new project should have been given to him before he came here
