Why are me and my brothers and sisters different, even though we have the same mummy and daddy

Genetics. You have to be pretty well-rested to get your head around it, and after last night's performance from my 18-month-old, well-rested I am not. I wonder if wakefulness is genetic? Here goes, anyway...

It is possible for two non-twin siblings to be identical, but very very unlikely. On average, we are 50% genetically similar to our siblings. Tell that to my two boys, who constantly get asked if they are twins!

Your commonplace human being has 23 pairs of chromosomes in nearly every cell of their body. One exception is in the man's sperm and in the woman's egg cells, where there are only half the number of chromosomes, one of each of the 23 pairs. To ensure that we don't end up all looking the same, when the pairs split in a sperm or egg cell, a process called recombination occurs, which is basically a scrambling of the DNA in each chromosome.

When a baby is made, the 23 chromosomes in the sperm and the 23 in the egg match up, making a unique human being, which has two copies of each of its unique genes.

So imagine the mother, with two copies of her own genes, meets with the father, who has two copies of his genes, then each trait they pass to their children is like the flip of a coin. Heads, you get stubbornness, tails you get double-jointedness, etc. It is very unlikely that you will get the exact same combination of heads and tails on 23 flips of the coin, two times over.

Make sense? Of course it doesn't, it's about the human body, a magical machine.

Mummy gave you this, daddy gave you that

If your child did ask this question, I guess the best way to explain it would be to say that you are half mummy and you are half daddy, but there are many different ways in which you can be like mummy and many different ways you can be like daddy. So each of your siblings is like mummy and like daddy in different ways.

Science fiends, please feel free to correct me in the comments!

Why do bees make honey?

The answer to this month's Why is actually pretty simple, however, I did find out a few other...buzzy...facts while researching it. Haaa. Sorry.

Bees make honey to fuel the hive over the winter time, when there is a shortage of nectar from flowers. So are we stealing their food? Well, it seems bees are so adept at making this store that each hive creates far more than they need, leaving plenty of the sweet stuff for us. However, I have read that a good beekeeper will leave enough of the bee's honey stores in the hive in case the bees should need it, or even store a little out of the hive in case they run out. 

How does the hive work?

The hive is made up of a Queen (you can call her Queen Bee), drones, and worker bees. 

The Queen is selected at 2 days old by the drones. She is there just for bee-making, and mates with the drones, who are also there just for this purpose. If the hive gets short on food, drones are often kicked out. 

The ones who mate with the Queen though, die immediately. I guess the other ones just hang around.

The worker bees are smaller and do all the work. Well, the other work. They collect nectar to make honey and feed the Queen and her babies, guard the hive from thieves, and keep the hive cool with the beat of their wings! They also produce the honeycomb the honey is kept in. 

The drones are male, by the way, and the workers are female. Just saying.

This article very clearly explains how the Queen is selected, in case you are interested.

Why honey?

Honey contains many nutrients and a high sugar content. so it's perfect energy food for active bees. The high sugar content and honeycomb storage means it keeps practically forever, as no fungi and the like can live in all that sugar. 

Next month

I have had a request for a genetics based question, which I have simplified to the following:

Why are me and my brothers and sisters different, even though we have the same mummy and daddy?

Wish me luck with that one!

Why do I have to wash my hands?

Welcome back, I hear you say. Where you been? Good question, but not as good as my first Why of 2014. 

I have a monster of a cold sore at the moment. Actually, it's more like several cold sores, and they're spilling down from the corner of my mouth like poorly applied lipstick, only not as attractive. I am hopeful (but feel it is unlikely) my boys don't catch the pesky virus that causes these unsightly menaces.  For this reason, I try to keep them away from any cups or cutlery I have used while sporting one. I also try not to kiss them, which is hard, and try to keep their hands away from my face, which is pretty much impossible.

So yesterday the baby was reaching for my homemade iceblock, despite the fact he had his own in the other hand (other people's treats look so much tastier than your own). "No," I said, "you don't want mummy's one. You might catch my cold sore."

"What you say mummy?" asked the nearly-three. "Is there sores on your iceblock?"

This wasn't exactly a Why, but it did lead to a lot of Whying, so I decided to find a better way to explain germs to kids. 

What are germs?

Well, in this context, germs are little illness causing pests that get into our bodies through our noses, mouths, eyes (or even bottoms!), usually through our hands touching a surface or another person that has that germ on them.

Germs are little organisms that come in 4 forms: Bacteria, Viruses, Fungi and Protozoa.

Bacteria can be good, but the ones we need to watch out for are the ones that like to find their way inside our bodies and cause infection. Bacterial infections can be sore throats, tooth cavities or ear infections.

Viruses need to find a home inside a living thing, or they cannot survive. If you have a virus inside your body, you are its host, even if you don't want to be! Most viruses are fought off by your body, but some, like the coldsore virus, stop reproducing and have a little sleep for a while inside our bodies, then come back out now and again. Grr.

Fungi, like mould and mushrooms, like to grow in dark, damp places. Fungal infections are not usually dangerous, but can be uncomfortable. Babies can get fungal rashes if their damp nappies are left on too long.

Protozoa are organisms that like to live in water. When they get inside us, they can cause vomiting and diarrhea.

How are they spread?


Well, it's pretty obvious isn't it, but how do we get it through to our mucky little people who are too busy to wash their hands? When researching this question, I came across this excellent website which explains a fun way to show kids why they need to wash their hands, using glitter.

My boy is quite into looking at microscopes and magnifying glasses at present, so perhaps another way to show kids there is more out there than what they can see, would be to use a microscope or glass as an example.

See, the spider you killed has little hairs on his legs, but we couldn't see those before. Well, it's possible the sandpit has lots of little germs in it that could give you a cold or a sore tummy, so we should wash our hands before we eat lunch....

Worth a try.

Next month (yes, it's monthly now, I'm busy)

Why do bees make honey? Buzz, buzz, buzz, I wonder why he does!