Mission (Im)possible?

In today's lesson on Heredity - Phenotypic Variations, you saw how each of us differ in various traits and charcteristics.

Here's a mission for you all:

There is ONE male teacher who sits in Staff Room 1, who has a COUNTER-CLOCKWISE hair whorl!

Can you find out who he is? =)

Clue: He is a science teacher.

Would You Consider Abortion in These Situations?

Disclaimer: The following is taken from various Internet sources, and contains religious inclinations. It does not aim to impose any religious ideologies.

A man raped a 13 year old black girl and she got pregnant. If you were her parents, would you consider recommending abortion? 

There is a preacher and wife who are very, very poor. They already have 14 kids. Now she finds out she is pregnant with her 15th. They are living in tremendous poverty. Considering their poverty and the excessive world population, would you consider recommending abortion? 

The father is sick with sniffles, the mother has TB. They have 4 children. The first is blind, the second is dead. The third is deaf and the fourth has TB. The mother finds she is pregnant again. Given the extreme situation, would you consider recommending abortion?

A teenage girl is pregnant. She is not married. Her fiancée is not the father of the baby, and he is very upset. Would you recommend an abortion?


If you have answered “yes” to any of these situations:

In the first case you would have killed John Wesley, one of the great evangelists of the 19th century.

In the second case, you would have killed Beethoven.

In the third case you would have killed Ethel Waters, the great black gospel singer.

In the fourth case you would have recommended the murder of Jesus Christ.

2.3 Reflections on ART

In today's lesson, you have learnt about the various forms of ART, and how to identify the most appropriate ART for certain infertility issues. You also had a discussion on ethical issues surrounding surrogacy and the rights of a child conceived via ART.

Now, reflect individually on the following questions as a guideline, while incorporating Elements of Thought. Submit a min 100-word reflection by Friday 11:59pm through e-mail. You may wish to include any other points in your reflections.

Information: 3 things I have learnt about Assisted Reproductive Techniques – differences, affordances, advances, etc.

Implications/Perspectives: 2 impacts of such advances in human reproduction on families and society

Consequences: 1 way to reconcile adverse human emotions towards such medical advances

2.2 Assisted Reproductive Techniques

For the upcoming lesson on Assisted Reproductive Techniques, please visit http://www.nytimes.com/2010/10/05/health/research/05nobel.html
http://www.artificialinsemination.net/
http://www.moh.gov.sg/mohcorp/mediaforums.aspx?id=4632.
to learn more about assisted reproductive techniques.

You will need information gathered from these two sites to complete ExB6 as well as the interesting tasks in the next class!

AND finally, the newest update on AIDS

Drugs Can Avert HIV Infection

http://news.discovery.com/human/hiv-infection-prevention-110713.html

Rose Palazzo
July 14, 2011

For the first time, studies show that AIDS drugs taken daily can cut "by more than half a person’s chance of becoming infected with HIV through heterosexual intercourse," according to the Washington Post.

"This is a good day for HIV prevention," Dr. Lynn Paxton, HIV research coordinator for the Centers for Disease Control and Prevention, said to the Associated Press about the promising new findings.

The first of the new studies, run by the Centers for Disease Control, involved more than 1,200 men and women in Botswana. About half received Truvada, an HIV treatment made by Gilead Sciences Inc. The other half received a fake pill.

An analysis found four of those on Truvada became infected with HIV, compared to 19 on the dummy pill. That means the real drug lowered the risk of infection by roughly 78 percent, researchers said.

The second study was funded by the Bill & Melinda Gates Foundation and run by the University of Washington. It involved more than 4,700 heterosexual couples in Kenya and Uganda. One partner had HIV and the other did not. The uninfected were given either daily placebos, Truvada pills, or another Gilead treatment, Viread.

The study found 13 HIV infections among those on Truvada, 18 in those on Viread, and 47 of those on dummy pills, according to the AP. So the medications reduced the risk of HIV infection by 62 percent to 73 percent, the researchers said.

Another report announced last year was not as promising.  The study of Truvada involved gay men in Peru, Ecuador, Brazil, South Africa, Thailand and the United States. The drug lowered the chances of infection by 44 percent, and by 73 percent or more among men who took their pills most faithfully.

It was thought to be a huge triumph. But then in April, an interim analysis of the study of 3,900 women in Kenya, Tanzania and South Africa did not show a benefit.

"Scientists are still piecing together why that study pointed to failure and the two latest indicate success. One theory is that the women in the earlier study did not take the medication as often as they should have, Paxton said," the AP reported.

Gonorrhea - its a BACTERIAL infection!

For those of you who missed out on this important information...

Drug-Resistant Gonorrhea Strain Emerges

http://news.discovery.com/human/gonorrhea-resistant-drugs-110711.html

 

July 12, 2011 1:32:00 AM

For the first time, international researchers have identified a strain of gonorrhea that is resistant to treatment with antibiotics, scientists announced at a sex disease research conference Monday.

The common bacterial infection, often called the "clap," has until now been easily treatable with antibiotics but if left alone can cause infertility in women and painful urination and a pus-oozing infection in men.

"This is both an alarming and a predictable discovery," said Magnus Unemo of the Swedish Reference Laboratory for Pathogenic Neisseria. "Since antibiotics became the standard treatment for gonorrhea in the 1940s, this bacterium has shown a remarkable capacity to develop resistance mechanisms to all drugs introduced to control it."

Details of the discovery were to be released by Unemo and colleagues at the 19th conference of the International Society for Sexually Transmitted Disease Research, on from July 10-13 in Quebec City, Canada.

Since the finding is so new, scientists are unclear how widespread the resistant strain may be in the world population, but concerns are mounting that it could spread quickly. "While it is still too early to assess if this new strain has become widespread, the history of newly emergent resistance in the bacterium suggests that it may spread rapidly unless new drugs and effective treatment programs are developed," Unemo said.

As many as 700,000 people in the United States are believed to get gonorrhea annually, according to the Centers for Disease Control and Prevention. Up to half of infected women experience no symptoms, while men usually see signs of infection within two to 30 days.

"Anyone who has any type of sex can catch gonorrhea," according to the US National Institutes of Health, which notes however that risks are higher among people with multiple partners and people who have unprotected sex. "Gonorrhea is more common in large cities, inner-city areas, populations with lower overall levels of education and people with lower socioeconomic status," added the NIH.

People who suspect they may be infected should see a doctor in order to obtain a prescription and should not attempt to treat the problem themselves, experts say.

The current treatment recommended by the CDC is an single dose pill of an antibiotic called cefixime, or a single dose of azithromycin (Zithromax) for people who are allergic to penicillin, ceftriaxone or cefixime.

Penicillin is no longer considered the standard treatment because it was previously found to be ineffective in some cases.

1.7 The birds and the bees

It is an expression often used in reference to teaching someone about sex and pregnancy. In the olden times, the birds and the bees is a metaphorical story used to explain the mechanics and good consequences of sexual intercourse by referring to commonly seen natural events. For instance, the idea of bees carrying and depositing pollen into flowers explains male fertilisation, and that of birds laying eggs explaid female ovulation.

But, the mechanics of courtship and sexual intercourse of the birds and the bees can be very, very different from that of humans. Do you know how they attract partners and mate?

Frigate Birds

Compared to the mating rituals and accesories of peacocks, the frigatebirds are so much more awe-inspiring! A male frigatebird inflates his red throat sac into a giant heart-shaped balloon. This takes an immense effort, and 20 minutes. He then does a courtship dance by waggling his head from side to side, spreading and shaking his wings, and calls the females to take a good look at him.

A female frigatebird then makes her choice after the viewing, and usually the male with the biggest and shiniest balloon wins. During sexual intercourse, the male bird may even possessively put his wings over her eyes to ensure that she does not get to see other males with grander balloons!


Honey bees



A female bee is selected to be bred in a designated compartment in the bee hive. She is then fed a special diet of royal jelly by worker bees to induce maturation of her sexual characteristics.

This queen bee will proceed to go on a mating flight with about 15 - 20 male bees, otherwise called drones, picked out from tens of thousands eligible bachelors in the colony. However, this is a "kamikaze" mission, because during mating, their genitals explodes and the penis snaps off inside the queen!

This bizzare phenomenon is actually a "for the sake of honey bee-kind" philantropic act. The penis left inside the queen acts as a plug to prevent other drones from fertilizing her.

Watch the mating of honey bees here.

1.6 Advocating abstinence or contraception?

New campaign targets teens, promotes responsible sexBy Hoe Yeen Nie, Channel NewsAsia | Posted: 07 October 2007 0011 hrs
SINGAPORE: The number of teenagers contracting sexually-transmitted diseases has doubled in the past five years.

Teen abortions have also not gone down. The worrying situation is despite sexuality campaigns that encourage teens to say 'no' to sex. So some are calling for a change.

One group is advocating the message that if you're saying 'yes' to sex, do it responsibly. Bayer Healthcare and web portal Youth.SG say telling teenagers to abstain from sex is no longer realistic. They believe that what is needed now is to teach youth about responsible sex.

And that means, keeping the message of saying 'no' but at the same time, promoting the use of condoms and oral contraceptives. They hope to promote this message with the help of mascots.

But some feel that there is no side-stepping the issue, even when sex is still largely seen as a sensitive topic in Singapore. Associate Professor P C Wong, chief of Obstetrics and Gynaecology Department at the National University Hospital, said: "The statistics speak for themselves. Every year, as I said, 1,300 to 1,500 teenage abortions occur. The numbers have not dropped. And STDs (sexually-transmitted diseases) have gone up, more than double. So we have to sit up and pay attention to the statistics."

"The statistics are giving us a signal, that there's a lot of teenage sexuality out there, and we have to teach our teenagers to be sexually responsible," he added. Latest figures from the Ministry of Health put the number of teen abortions in 2005 at 1,279. And in 2005, 678 teens aged between 10 and 19 years sought help for sexually-transmitted diseases, compared to 256 in 2001.

Also, a recent survey showed that four in 10 sexually active women did not use any form of contraception. This is according to the Whisper Study, which was conducted between September 2003 and December 2004.

In a statement to Channel NewsAsia, the Singapore Planned Parenthood Association said it supports the campaign to encourage teens to be sexually responsible. It said this will promote comprehensive understanding of sexuality and reproductive health. It added that it will help the people identify their own values and make decisions.

But SPPA stressed that it does not discourage abstinence. Parents Channel NewsAsia spoke to, would rather teens say a complete 'no' to sex. "Even though they are taught to use condoms or whatever, it's better not to do it," said a Muslim woman.

"Contraceptives? At this age, if you ask them to use contraceptives, that means you're encouraging them (to have sex) by using condoms and contraceptives," said a Chinese woman.

Opening up a Pandora's box? This is what Bayer Healthcare and Youth.SG hope to achieve with their latest campaign. They hope the campaign will start a discussion on issues related to teenage pregnancies and sexually-transmitted diseases. They are working with the Republic Polytechnic to expand the programme.

Test your knowledge on condoms

Think you know ALL about condoms?
Try out this quiz! http://msn.shoppinglifestyle.com/sg/quiz/condom/

1.5 A Molecular Condom Against AIDS

A Molecular Condom Against AIDS

A group of scientists from University of Utah have designed a "molecular condom" that women could use to prevent AIDS. This involves inserting a liquid into the vagina, where it would turn into a gel-like coating and then, when exposed to semen, return to liquid form and release an anti-viral drug.

The molecular condom is part of a worldwide research effort to develop "microbicides" -- drug-delivery systems such as gels, rings, sponges or creams to prevent infection by the human immunodeficiency virus and other sexually transmitted diseases.

Microbicides are seen as a way for women to gain power by protecting themselves from HlV,
particularly in impoverished nations where AIDS is widespread, where rape is rampant or where conventional condoms are taboo, not reliably available or where men resist using them.

About 16 microbicides are in development and five are undergoing testing in thousands of women, mostly in Africa. They are designed to fight HIV infection by preventing the virus from entering cells or dividing, or by maintaining acidic vaginal conditions. No first-generation microbicide has been approved yet for widespread use.

"The ultimate hope for this technology, is to protect women and their unborn or nursing children from the AIDS virus, but the molecular condom is five years away from tests in humans and roughly 10 years until it might be in widespread use," says Patrick Kiser, an assistant professor of bioengineering. On 11 Dec 2006, Kiser and his colleagues have published their study online, in the Journal of Pharmaceutical Sciences.

(Adapted from http://www.sciencedaily.com/releases2006/12/061212091937.htm)

Now something for you to think about and comment on...

Information: How is the molecular condom different from and similar to a normal male condom, in terms of function?

Implication/Consequence: If this molecular condom proves to be effective, how can it help prevent the spread of AIDS from women to their next generation, thereby reducing the number of AIDS cases over time?

Perspective: How does using the molecular condom empower women "particularly in impoverished nations where AIDS is widespread, where rape is rampant or where conventional condoms are taboo, not reliably available or where men resist using them"? Does using the molecular condom protect them from actual rape cases and the associated psychological trauma?

Assumption: How can we be sure that the women the molecular condom is especially targeted for know how to use it, and will use it? Who gives them access to the molecular condom, and who will educate them on its use?

And to test your comprehension and thinking...

Which of the following cannot be inferred from the passage above?

A For development of new technologies, time and size of scale are required for trial and improvements.

B Teamwork and perseverance are important for doing scientific research.

C Communication of experimental results is part of research.

D Science can solve all problems to improve our environment.

How did syphilis came to be so well-documented?

The following article was retrieved 27 June, 2011, from http://theoligarchkings.wordpress.com/2010/10/02/guatemala-pox-bananas-and-american-exploitation/

Guatemala : Pox, Bananas and American Exploitation

By David Macadam

Syphilis, the face of American Exploitation 

It seems it wasn’t just bananas.  A report has shown us that during the late forties American scientists took advantage of the fact that The United Fruit Company had a throttle hold on Guatemala, and used its people and institutions to conduct vile medical experiments on its weakest and most vulnerable citizens including children as young as six.

At the very time that America on one hand was trumpeting its highest virtues at the trials at Nuremburg of Nazi doctors, where medical doctors ( Beiglbock, Brack, Karl and Rudolf Brandt, Hoven, Murgowsky and Sievers) were all found guilty and subsequently executed for having used prisoners and children in ghastly medical experiments, she was herself conducting experiments on brown foreign people, by deliberately giving them syphilis and gonorrhoea so they could test various cures.

Some of us may remember the horror and outrage that accompanied the discovery during Clinton’s presidency of the infamous Tuskegee tests in Alabama where black sharecroppers, who already had syphilis were callously observed over the rest of their lives so the course of the disease could be tracked scientifically.  These experiments had run from 1932-1972.  During all that time they were left to suffer and no treatments were given.

It seems, according to the evidence of Professor Susan Reverby of Wellesby College, that the scientists at Tuskegee went one stage worse.  In Guatemala, off-site, down south, hidden away from the eyes of the American public, secreted from the scrutiny of their fellow doctors and their professional bodies, they deliberated infected prisoners and mental health patients and even used children from the state orphanage.
Was it meant to be all right because they were, poor, brown and powerless?

Professor Reverby’s report “Normal Exposure” and Inoculation Syphilis : A PHS Tuskegee Doctor in Guatemala 1946-8, is disturbing.

The United Fruit Company, owned largely by oligarchical American interests, had owned and controlled Guatemala in the first half of the twentieth century.  (If you click the link you will go to my previous post).  PHS were looking for somewhere to hide this research unit ,and Guatemala was far enough away, but still close enough for travel to be perfect.  In a country as tightly managed as Guatemala was by the oligarchy and the Fruit Company it is inconceivable that they did not know and authorise these experiments.  Indeed the control by the Fruit Company let PHS run unbothered by what the locals might have thought.PHS wanted victims to infect so they could test various types of anti syphilis agents in that immediate first post infection stage.

Syphilis is difficult to keep alive outside the human body.  It can’t be grown in vitro in the lab so they infected their victims in the prisons and mental institutions by using pox ridden prostitutes.  The prostitute bit seemed to work as the prisoners did not know what was going on.  They resisted the blood testing though, so the scientists moved to prey that was easier to manage.  They chose children from the state orphanage (some as young as six) for the blood tests.

Americans love vampire stories.  I assume this is going down a treat.

The White House described it as “shocking”, “tragic”, “reprehensible”.  But didn’t mention compensating the victims.

So why bring this sad tale up after half a century?  Do I need to regale you with another “bad old days” story of a time before institutional oversight, modern review boards, proper medical ethics committees?

Well yes, and indeed even more so today.  What this tale tells us is that the doctors and the companies knew full well what they were doing was wrong and evil.  Their own country was actively hanging Nazi doctors at that time for just such experimentation.  They deliberately sought dark places controlled by Americans, far from professional and public scrutiny, where they could do as they willed.  Places that today are marked for extraordinary renditions, secret prisons, closed to the media and shut away from professional oversight.
What dark horrors are being done today out there in the name of America?

Copyright David Macadam 2010

1.4 Test your knowledge on contraception!

Think you know all about CONTRACEPTION?

Then try your hand at piecing together a concept map! Go to the following website http://www.scribd.com/doc/58902900/Class-Exercise-3-Contraception and download the powerpoint presentation in the pptx. format. Simply follow the instructions inside.

The first student from each class to e-mail me the correct answer (in the format FullName_Class_contraception.pptx) will win for himself a small prize!

The sex-changing chicken

The following article was retrieved 14 May 2011 from http://www.lifeslittlemysteries.com/

Sex-Change Chicken: Gertie the Hen Becomes Bertie the Cockerel

By Remy Melina, Life's Little Mysteries Staff Writer
31 March 2011 

Credit: Poultrykeeper.com

A British couple was surprised to witness their pet hen Gertie gradually transforming into a rooster. No, this is not an early April Fools' Day prank. Chickens really can undergo natural sex changes.

The first sign that something was afoot with Gertie was that she stopped laying eggs, her owners, Jim and Jeanette Howard of Huntingdon, England, told the local media. Next, she began strutting around their garden and crowing like a rooster. Over the next few weeks, Gertie put on weight and developed wattles beneath her chin, a feature normally exhibited only by males. She also grew dark brown plumage and a scarlet cockscomb atop her head, both male traits.

''I know it sounds ridiculous but I can assure you it's all true," Jim Howard told cambridge-news.co.uk. "People think it's a bit weird but apparently its one of those things that does happen."

"Sex reversals do, in fact, occur—although not very frequently," states a 2000 report published by the University of Florida's Institute of Food and Agricultural Sciences. "To date, however, spontaneous sex reversal from male to female has not been reported."

That's because the mechanics of this biological phenomenon seem to work in only one direction. Normally, female chickens have just one functional ovary, on their left side. Although two sex organs are present during the embryonic stages of all birds, once a chicken's female genes kick in, it typically develops only the left ovary. The right gonad, which has yet to be defined as an ovary, testes, or both (called an ovotestis), typically remains dormant.

Certain medical conditions—such as an ovarian cyst, tumor or diseased adrenal gland—can cause a chicken's left ovary to regress. In the absence of a functional left ovary, the dormant right sex organ may begin to grow, according to Mike Hulet, an associate professor at Penn State University's department of poultry science.

"If the activated right gonad is an ovotestis or testes, it will begin secreting androgens," Hulet told Life's Little Mysteries. Androgens are the class of hormones that are largely responsible for male characteristics and are normally secreted by the testes. "The production of androgen would cause the hen to undergo behavioral changes and make it act more like a rooster."

The hen does not completely change into a rooster, however. This transition is limited to making the bird phenotypically male, meaning that although the hen will develop physical characteristics that will make her look male, she will remain genetically female. So while the hen will no longer lay eggs, she won't be fathering any offspring, either.

As for Gertie, the Howards have renamed the hen Bertie after her sex change.

Week 1 FAQ

This post answers a number of questions your peers have raised, which you may be wondering as well. It will be updated as and when there are incoming relevant questions from the post box!

Why does body temperature increase when ovulation?
After the release of an ovum, the remaining cells of the Graafian follicle, the corpus luteum, will produce the hormone progesterone, which you know inhibits FSH production (thereby preventing other follicles from maturing) and maintains the uterine lining. Progesterone is also responsible for the raise in body temperature.

Does the blastocyst stage come after the embryo or before?
The blastocyst (see picture below) is actually a stage of embryonic development! Blastocyst formation begins around day 5 after fertilization in humans.

 

Once the zygote undergoes its first cell division, it is called an embryo. In humans, it is considered an embryo until about 8 weeks after fertilization, and thereafter it is instead called a foetus.

 

What happens when menopause occurs? Does it mean that the woman has run out of eggs?

Menopause occurs due to a complex series of hormonal changes.When menopause occurs, menstruation stops and ovulation ceases, and the female can no longer become pregnant. But it is not triggered by an absence of ova.

A female is born with all the eggs she needs, which averages 1.5 million.When menstruation begins, one ovum is released every 28 days. Occasionally, 2 or 3 may be released (resulting in fraternal twins/triplets if fertilised). So, if menstruation commences at age 15 and continued up to age 55, around 522 eggs would have been released. 522 is a far cry from a million!

However, by the time a female reaches menopause age, most of the ova may become no longer viable due to two reasons:
1. The number of eggs in the ovaries decreases with age. When the female reaches puberty, there are only about 400,000 eggs available for fertilization. Each month several follicles are stimulated to mature [recall video in class], but only 1 will release an ovum.
2. Ova have to be healthy (e.g. correct shape, physiology, DNA) in order for an embryo to develop to a healthy baby. need to have the right shape, health, and chromosomes in order to be able to develop into an embryo and, eventually, a baby. But with age, quality of the ova decreases, due a process called atresia (the degeneration and subsequent resorption of immature ovarian follicles - fluid filled cysts that contain the eggs).

What does the pubic bone do in humans?

Also known as the baculum, the penis bone is a bone found in the penis of most mammals. However, it is absent in humans! In humans, the rigidity of the penis erection is provided entirely by blood pressure, as blood fills up the erectile tissue within the penis.

Richard Dawkins proposed that the loss of the pubic bone is a result of sexual selection by females looking for signs of good health in prospective mates. For the penis to solely rely on blood pressure to achieve a rigid state makes it particularly vulnerable to blood pressure variation. Hence, poor erectile function reveals physical states such as diabetes and neurological disorders, and mental states such as stress and depression. [Relate this to the inability to engage in sexual intercourse if the male has erectile dysfunction, resulting in the inability for sperm to be deposited in the female via sexual intercourse.]