Chapter 5: Genetics (Variation I)

Learning standard: 

Communicate about continuous variation and discontinuous variation

Hi students. How are you? I hope you and your family are doing fine and stay at home. In today's lesson, we are going to learn about variation. What is variation? Now look at the picture below.

Do their face look the same (like twins) or they look different? Of course they look different. Generally, all humans in the world look different. From Europe to Asia, we are different or varied in terms of hair colours, skin colours, height, weight or even blood group. So, variation in science means any difference between individual caused by either genetic or environmental factor.

There are two types of variation. The first one is called continuous variation and the second one is call discontinuous variation.

Continuous variation is

• the characteristics can be measured on scale such as human height, weight, skin colour and etc.
• cannot be grouped into distinct and discrete phenotypes.
• usually quantitative and are determined by genes and influenced by environmental factors.
• Examples of continuous variation are human height, weight, skin colour and etc.

Diagram 1: Variation in human height

Discontinuous variation is

• the characters are discrete and cannot be measured on a scale.
• qualitative
• usually determined by a single gene with distinct effect.
• Examples of discontinuous variation are ability to roll tongue, blood type, fingerprint and etc.

Diagram 2: Variation in ability to roll tongue

Now you already know what is variation and types of variation. Let us do some exercise. 

Exercise:

1. What is the difference between continuous variation and discontinuous variation? 

Write down in the comment below and do not forget to write your name and class. For example: Continuous variation has no distinct categories while discontinuous variation has distinct categories. - Vanessa (4A)

For Question 2 and Question 3, choose only ONE question to answer.

2. Plot a histogram graph based on the table below. Draw the graph on a graph paper and post it in the class group.

Height (cm)	130-134	135-139	140-144	145-149	150-154	155-159	160-164	165-169
No of students	3	5	8	12	11	7	2	1

Example:

3. Plot a bar chart based on the table below. Draw the graph on a graph paper and post it in the class group.

Blood type	A	B	AB	O
No of students	5	7	3	10

Example:

Make sure you complete the exercise by today (22nd April). 
That's all for lesson today. Stay healthy and stay safe.

Chapter 5: Genetics (Genetic Engineering Technology)

Lesson Date: 17th April 2020

Learning Standard: 

Discuss genetic application to increase living quality. (gene therapy, forensic science, genetic genealogy)

INTRODUCTION

Hello students. How are you? I believe that you already know what mutation is, examples of mutation and factors that cause gene mutation and chromosomal mutation.

Today, we are going to learn about how genetic application can increase living quality. But before I start with the lesson today, make sure that you have your textbook with you.

Have you heard about genetic engineering technology? What is genetic engineering technology and why is it important to us?

• Genetic engineering refers to the direct manipulation of DNA to alter an organism’s characteristics (phenotype) in a particular way. 
• Genetic engineering, sometimes called genetic modification, is the process of altering the DNA in an organism’s genome.
• It may also mean extracting DNA from another organism’s genome and combining it with the DNA of that individual.
• Genetic engineering can be applied to any organism, even virus. (hmm, for example, is corona virus that cause COVID-19 is genetically modified? If it is genetically modified, it means that men has changed the DNA of the virus)
• For example, genetic engineering can be used to produce plants that have a higher nutritional value or can tolerate exposure to herbicides.

DNA RECOMBINANT TECHNOLOGY 

Students, I want to show you one example:

• People with type 1 diabetes have problem to produce insulin in their pancreas.
• Therefore, they have to inject insulin to control their blood sugar levels.
• Genetic engineering has been used to produce a type of insulin, very similar to our own, from yeast and bacteria like E. coli.
• This genetically modified insulin, ‘Humulin’ was licensed for human use in 1982. 

The example above is called DNA recombinant technology where human or animal or plant DNA can combine with bacteria DNA. Or we can combine animal DNA  with human DNA. Wow! this remind me of Spiderman. He got bitten with spider, their DNA combine and he become Spiderman! Well, it is only happen in movie. But the real thing is, to combine DNA with other DNA, it can only be done in the laboratory. 

So, let's watch this clip so that you have a better understanding on how insulin can be produced through DNA recombinant technology.

GENETICALLY MODIFIED ORGANISMS

Another example of genetic engineering is genetically modified organisms (GMO). Have you heard about GMO? If you don't, now look at the picture below.

Why do we need to produce GMO tomato? Click this link and read more about GMO. http://www.weareheretoinspire.com/gmo-vs-organic/

Now, let's look example of GMO or transgenic organisms that have been produced for human benefits.

Students, how does genetic engineering affect our life? There are pros and cons about genetic engineering. Now let's watch this video. 

There are many more genetic engineering technology such as gene therapy, forensic science, genetic genealogy, cloning and etc. Please look up in the Internet and read about it. 

PRACTICE

Students, we have come to the end of the lesson. This is the exercise that you need to do and submit today, 17th April (Friday). Click this link https://forms.gle/e4mPwLv2e1MRSpYS8
and answer the question. 

THANK YOU, STAY AT HOME & STAY HEALTHY.