Archive for January, 2010

Greenhouses and photosynthesis

Thursday, January 28th, 2010

Take a look at this sheet (thanks Mr Boulton).  Greenhouse Assessment Task

It gives some background info on how greenhouses work, and finishes with some questions about the links with photosynthesis and respiration.

Limiting factors in photosynthesis

Wednesday, January 27th, 2010
photosynthesis in action by Sam Judson on flickr

photosynthesis in action by Sam Judson on flickr

Let’s suppose I want to redecorate my bedroom.  I need money to buy the materials, I need to know how to decorate, and I need the time to be able to do it.  Imagine that I am a good decorator, with a free weekend coming up, but I have no money to buy what I need.  The materials are the limiting factor in this instance.  The lack of paints, brushes, wallpaper, etc is what is stopping the process of redecoration.  Similarly, if I had money and knowledge, but was busy for the next month, then time would be the limiting factor.

Limiting factors apply to photosynthesis too.  We’ll discuss the factors that control how fast or how slowly photosynthesis proceeds, and analyse some graphs to help us understand this concept.

Is the main limiting factor for photosynthesis different in different parts of the world?  Or for different species of plants?  What do you think?

Ethical issues in human nutrition

Tuesday, January 26th, 2010
sweet, sweet honey by BotheredByBees on flickr

sweet, sweet honey by BotheredByBees on flickr

There are several issues to consider when choosing what we eat and what we buy to eat. 

Is it ok for us to consume animal products such as honey, eggs, milk and meat?  What are the ethical issues concerning including these in our diet?  Is it culturual?

Discuss the concept of food miles.  Is it appropriate for consumers to choose foods that minimize food miles?

Option E – Neurobiology and Behaviour

Tuesday, January 26th, 2010
Mr Gray Eyes by Tim in sanhazzay on flickr

Mr Gray Eyes by Tim in sanhazzay on flickr

Here is the syllabus guide for this topic. Option E – syllabus guide

We’ll be using notes and resources from click4biology.

The first section is all about stimulus and response, so we’ll recap a bit of the nervous system, particularly the stuff on reflex arcs.  We’ll then move on to explain how animal responses can be affected by natural selection.  You need to investigate two examples of this.  Use can use the blackcap bird (Sylvia atricapilla) as one, and any other of your choosing.

Moving on to perception of stimuli, we’ll study both the eye and the ear.  You need to be able to label a diagram like this one: Eye diagram  We’ll then do a dissection so you can identify the parts properly.

You will also have to:

  • annotate a diagram of the retina to show cell types and direction of light movement
  • compare rods and cones
  • explain the processing of visual stimuli (edge enhancement and contralateral processing)

We’ll then move on to the ear, and you will need to be able to label a diagram and explain how sound is perceived.  Here is a good presentation to help you get through all that!

Playing doctors

Monday, January 25th, 2010

We are going to do a little role-playing.  Here are two scenarios:

You are a new mother of a 2 week old baby.  Throughout your pregnancy you read a lot about breastfeeding vs bottle-feeding.  At your first doctor’s appointment since giving birth, the doctor asks you which method you have chosen, and why, and how it is going.  Script the conversation between you and the doctor.  Do some research to find out the composition of breast and bottle milk, and discuss the benefits and drawbacks of your chosen method.  Include ethical and social issues as well as medical ones.

You are a doctor who has recently confirmed a diagnosis of type II diabetes for a particular patient.  Script a conversation between you and your patient that includes what the causes and symptoms are, the relevance of ethnicity, what the dangers are, and any dietary advice (with justification).

Health issues and diet

Friday, January 22nd, 2010

We are going to use click 4 biology to help us through this section.

You need to be able to:

  • Calculate the body mass index (BMI) of a person.  Know the correct units.
  • Use BMI to distinguish between being underweight, normal weight, overweight and obese.
  • Recognize the limitations in using BMI alone as an indicator of weight.
  • Outline the reasons for increasing rates of clinical obesity in some countries.  There are several.
  • Outline the consequences of anorexia nervosa.

Energy in human diets

Friday, January 15th, 2010
fine crop of rice by shop boy on flickr

fine crop of rice by shop boy on flickr

Did you know that per 100g, carbohydrates and proteins contain similar amounts of energy whereas fats contain more than double that?  Actual figures are: 1760 kJ for carbohydrates, 1720 kJ for protein and 4000 kJ for fats (per 100g).

Differences exist between various ethnic groups in terms of their main dietary source of energy.  Your task will be to research different ethnic groups that use rice, wheat, cassava, maize, fish and meat as their staple energy source, and to compare their diets.


MSG by PunkJr on flickr

MSG by PunkJr on flickr

In addition, we will consider that there are social issues relating to inappropriate diets, especially in the developed world.  There is also highly effective marketing of unhealthy foods by profit-making companies (I saw a TV ad recently espousing the benefits of MSG!).  With this in mind, you must be able to explain the possible health consequences of diets rich in carbohydrates, fats and proteins. [Consequences of an excess of each type of nutrient should be explained separately.]

What makes us stop eating?  We have an appetite control centre in the brain.  Do some research and find out how it works.

Global applications – energy transfer on the planet

Friday, January 15th, 2010
Planet Earth by regulus2007

Planet Earth by regulus2007

Each table will be given one of the following questions to research.  Find out all you can, remembering to discuss heat transfer in your answers.   Then we’ll share our findings with the class. The link below each question takes you to a youtube clip that will help to get you started.

And our old friend Bill Nye has something to say on climate 🙂

Nutritional analysis

Friday, January 15th, 2010
kids understanding food labeling by nutrition education on flickr

kids understanding food labeling by nutrition education on flickr

You have been asked to keep a food diary over the past few days.  In class we will use this database to input everything we ate or drank for a 24 hr period, and find out how healthy our daily diet is… or not!

We’ll then compare our diets to an imaginary fast food diet and see which is more nutritious.  You could also compare your week day to your weekend diet.


Heat transfer

Tuesday, January 12th, 2010
Thermal Fluid Dynamics by Pro-Zak on flickr

Thermal Fluid Dynamics by Pro-Zak on flickr

This week we’ll be learning about the 3 different processes of heat transfer: CONDUCTION, CONVECTION and RADIATION.  To help us, we’ll be talking soccer and basketball – watch this space!

Here are some videos to help demonstrate:  Bill Nye 1, Bill Nye 2, Bill Nye 3

You might want to try answer the questions on this worksheet courtesy of Mr Boulton while watching: Heat Transfer – Questions For Understanding

To find out whether you’ve really understood the applications of heat transfer, you will be given a challenge.  See the attachment to read more 🙂  Have fun!  Heat Transfer Patent office modified version

The powerpoint I used in class is here: Topic 03 – Thermal Physics  The text is a little advanced for G9, but the images are good.