Learning Biology at the Singapore Zoo -
Two Gametes forms A Zygote
Written Oct 14, 2001
"It is so boring, I don't want to go to the Zoo another Sunday morning," said
Jason a Secondary One student. "The Singapore
can't be having new exhibits like the White Tigers every Sunday."
The 13-year old boy was now taller
than his mother and soon wouldl be taller than daddy. He was not brought up to
appreciate wild life and animals. Most Singaporean pre-teens and teenagers
in 2001 had little contact with wildlife or visit the Zoo, in my
white tigers team up and relaxing on a cool October 9a.m Sunday morning.
The other one had a nap further to the right.
"Two's a company, three's a crowd" it seems.
"Mum and you go inside the Zoo while I wait outside," said the
tram ride was his idea of seeing all the animals at the zoo at the shortest possible time
during the previous visit 3 Sundays ago.
Nature does not appeal to him although he is a
close observer of issues affecting his health. "Will I die?" he would ask Mummy
when he had some cuts two years ago.
We were "Friends of the Zoo". Last year, we visited the Zoo once although we
could visit the Zoo more times, with the benefits of free entry for a family of four and
free car parking.
Elder brother Daniel, a Secondary Three student, was two years older and did not mind
going to the Zoo for breakfast on a Sunday morning. Recently he had attended an
"enrichment class" on life sciences. The lecture was on DNA.
white tigers did not have blue eyes as seen from afar.
"What is DNA?" I asked him.
"What is a chromosome?" I asked.
"No idea," Daniel replied.
"What is a nucleus?" I asked.
"How many chromosomes are there in a human cell?" I hope to
spark his interest in biology at the Singapore Zoo so that he
would become a doctor when he grew up.
"A few hundred." Daniel said. "Two gametes form a
zygote" he continued. That was the part he remembered
from the lecture.
"What is a gamete?" I asked.
"Can't define this term." he ate his French fries.
A Secondary Three student in Singapore would be
bombarded with so many subjects to learn in addition to extra curricular activities like
the National Cadet Corps. It is a wonder if he even passes his all 8 subjects at the
No point burdening him more with lectures.
"Let's look for the orange tiger," I
suggested. None was found on this October 2001. Three white
Bengal tigers were exhibited where the orange
tigers used to be.
"What's happened to the orange tigers?" I asked the zoo
people. Apparently they had relocated to the Night Safari.
Hoping to revive interest in biology, I asked Daniel: "What will be the colours of the cubs if you mate a white tiger with an orange
"If you are lucky, you get some white tiger cubs," said Daniel.
"Will you get white tiger cubs if you mate two orange tigers?" I asked him.
"No," Daniel replied. He could not elaborate further.
"Will you get white tiger cubs if you mate two white tigers?" I asked him.
"Yes," Daniel replied. "Something to do with dominance."
Sometimes I wonder how he could pass his Biology examinations
without understanding the fundamentals. The foundation of
Biology is weak and parents blame the poor quality of teaching
from the high turnover of teachers in many schools.
The teachers probably blame the poor quality of students. After
all, top students don't study Biology. I wanted Daniel to
study Biology and his teachers were surprised as he was eligible
for the Pure Science classes reserved for better students and
discouraged him from studying in the Biology class.
The technical terms like are new and hard for a pre-teen to understand or imagine.
structure is a double helix" according to Daniel's 4-page enrichment
"What is the meaning of helix?" I asked him.
"I don't know."
You don't see helixes in
real life. Neither do you see gametes or zygotes.
"Gametes are sex cells," I explained to Daniel. "They are either the
sperm or the egg. Each human gamete contains 23 chromosomes. When the sperm
fertilizes the egg and form a zygote, the zygote will have 46 chromosomes. The
zygote will divide into two cells which will divide again to form the heart, lungs, brain
and various organs of the body of a person."
Interesting but so what?
"The chromosomes are found in the nucleus of the cell. Each chromosome will be
made up of 2 strands of a ladder-like DNA which contains the genes." I said.
"Instead of the 2 straight two ends of a ladder, the strands are twisted around each
other left to right and right to left in a long chain. Such a structure is called a
double helix." I doubt if Daniel knows what the helical structure is, just by words
"Why is the tiger white coated?" I asked as we saw 3 white tigers
relaxing above a moat at 9 a.m. on a cool September 2001 Sunday morning looking
at the large crowd of children from a Utilities Board family gathering and
tourists. There were some explanatory notes on a plaque but Daniel did not bother to read them. How does a parent motivate a child to love
Biology when the parent does not know much about the technical terms
I told Daniel. "The gamete contains two genes, one from each parent.
One of the genes produce a white coat if there are two of them. If
there are two of the orange coat producing genes, an orange tiger cub will
Easier to say than to understand as genes cannot be seen.
"What if the zygote has a gene for white coat and one for orange coat?"
Daniel asked. "Do we get half orange and half white tigers?"
Mum was stumped as she had never studied genetics.
"Orange tiger cubs will be produced. This is because the gene for orange coat is the
dominant gene and such zygotes can only produce orange coated tigers."
This was a Sunday bonding with family. I did not want to lecture further. I only hope
Daniel would show a keen interest in acquiring knowledge in biology not so much as to pass
A natural interest in biology opens a whole new world of how to live a
healthy life, to enjoy a high quality of life money can't buy and to be kind to pets and
every living creature and plant in this earth.
This is again hard to explain in writing. It must be very tough for the ordinary teacher to
lecture on the double helix DNA with four protein bases, gene, gametes, zygote,
chromosomes, chromatids, enzymes, mitochondria, nucleus, cytoplasm organelles, meiosis,
mitosis and reticulated endoplasm to disinterested 13-year old boys not so
motivated to be interested in Biology. Mendelian genetics would be interesting if the
boys could have hands on experience in plant breeding.
always no time in the school curriculum for hands-on learning as compared
to text-book instruction.
It must be tough
for the average pre-teen to excel in Biology or life sciences as most of
them don't seem to have a passion or motivation in their daily living. If
teachers can use Pokemon cards trading and computer gaming
to teach, more male students will be highly motivated to
P.S. Update in 2008.
Digital pictures taken of the White Tigers at the Singapore Zoo
by Dr Sing in 2001 shown here are not up to standard. The mum
worries still and hopes that Daniel will pass his veterinary
examinations. As for Jason, he is in National Service Full Time.