Archive for the ‘G10 Int Sci’ Category

Saltwater vs freshwater ecosystems

Wednesday, March 30th, 2011

mangrove reflections by Claire `a Taiwan

Plants and animals that live in saltwater and freshwater must have special adaptations to cope with their particular environments.  They need to ensure that they can access water and oxygen at all times.  This can be difficult in circumstances where a plant’s root are surrounded by sea water, as this can affect osmosis. 

Your task is to select one freshwater animal and one saltwater animal and compare their adaptations in the form of a table.  You should then do the same for one freshwater plant and one saltwater plant.  The focus of this exercise is for you to identify the specializations of each species and how it is adapted for it’s environment.  Think about how it accesses water and oxygen.  Think about how it excretes waste.  Here are a few links to get you started, but you should extend your research beyond this.

How plants cope in the mangroves.  Mangrove trees.  How do plants survive in salt water?   Freshwater plant adaptations

Freshwater vs saltwater fish.    Animal adaptations.   Bullsharks.    Why do saltwater fish die when put in freshwater?

Water cycle

Friday, March 11th, 2011

rain by DRB62 on flickr

Your task is to research the water cycle, then create a story in comic life to represent it. 

You should include the following processes in your work: evaporation, precipitation, transpiration, condensation, infiltration, capillary action, run off. 

Here are a few links to help get you started: water cycle  more water cycle  brainpop video

What happened to my French fries?

Monday, March 7th, 2011

Once you have grasped the theory, you are going to demonstrate your understanding by tackling the following challenge:

You are a trainee chef working in the ISM kitchens.  You have had a hard day at work, and are just about to leave for home, when your boss informs you that you will be in charge of making French fries the next day.  You are excited about the responsibility being placed on you, so you decide to get a head start and peel and slice the potatoes that afternoon.  You place the cut potato pieces into water and leave them there overnight.  When you arrive the next day, you drain the water and are surprised to find that the potato pieces are all ‘pumped up and hard’ (like Sylvester Stallone in Rocky 4).  Your boss tells you that they cannot be used to make French fries, and suggests that you should have put some salt in the water.  He gives you the task of finding out what the ideal concentration of salt in water would be for leaving the potato pieces overnight without them becoming too hard or too soft.

You must design and carry out an experiment that allows you to answer the problem above.  Use the rubrics to guide you, but you must include the following headings in your report: FINAL Rubric design  FINALRubric DCP  FINAL Rubric CE

Research Question, Hypothesis, Variables, Apparatus, Diagram, Method, Results, Graph, Conclusion, Evaluation

Diffusion and osmosis

Wednesday, March 2nd, 2011

YouTube Preview ImageEver wondered how substances move into cells, or why, when you open the front door, you can smell your favourite food cooking in the kitchen, several rooms away?  The answer is diffusion.  We’ll talk about concentration gradients to explain how smells (the nice and the not so nice!) travel through the air.  Here is a useful animation to help you understand the process.

Osmosis is a form of diffusion that deals specifically with water.  Here is a good animation to explain what is going on.  This site goes into some detail about how osmosis affects living organisms and introduces some new vocabulary – hypotonic, hypertonic and isotonic.  Make sure you know what these terms mean.  Can you explain the science behind what is happening in the video above?

Empirical formulae

Tuesday, February 15th, 2011

House of Blue by nuttyxander on flickr

What is the difference between molecular and empirical formulae?  You need to find out.  Here is a set of practice questions on this topic.  7 emp form

This week we’ll do a lab where we determine the formula of hydrated copper (II) sulfate by experimental methods.  Read the lab sheet: formula of hydrated copper sulfate

To help you practice, there are tons of great resources out there on the web.  I have selected 4.  They are listed here in order of increasing complexity.

1. Nice worked examples.  2.  Another worked example for you to click through to find the solution. 3. Worked examples with extra problems, answers given.  4.  Fairly lengthy explanation of how to perform calculations. 

For some online practice, try this site.  And this worksheet has some excellent questions.  If you can do these you are all set!  Empirical and Molecular Formula Questions

The mole

Monday, February 7th, 2011

 

Dearest mole by zenera on flickr

We are going to step into some deep and sticky chemistry – and take a look at the term mole.  This is an important concept, so we’ll take it slow and steady.  This is a great resource to help us work our way through the topic.  Come back and revisit it often – until you feel you have a handle on it.  Practice, practice, practice! 

More useful information here.

Solubility graphs

Wednesday, January 26th, 2011

Here are the worksheets we used in class.  Print extra copies if you need to practice further. GCSE Water 04 big  GCSEWater03

This is the lab sheet for the KNO3 crystallization experiment.  Make sure you READ through the procedure before class so that you know exactly what to do when you get here.  solubility curve of potassium nitrate in water

Solubility

Tuesday, January 11th, 2011

Graduated cylinders and beaker filled with chemical compoundsSolute + solvent = solution

We’ll investigate factors affecting solubility by designing an experiment, then performing it and reporting on it.  Here are the rubrics that will be used to guide this. FINAL Rubric design  FINALRubric DCP   FINAL Rubric CE

This link has some useful information to help you explain your findings.

We’ll learn about saturated solutions and what actually happens when a substance dissolves.  We’ll also make some predictions as to the kinds of substances that can dissolve in water.

Water – the liquid of life

Thursday, December 2nd, 2010

pondskater by Robbie G1 on flickr

Our new unit is about OCEANS.  In this unit we will cover all kinds of interesting ideas, but we’ll start by looking at the structure and properties of waterThis site has a ton of information on water.  This is another good one.  These videos are useful to help you understand both the structure and the properties. One. Two. ThreeFour

Now try and answer these questions:-

  • Why are water molecules considered to be sticky?  Can you give examples of where this is useful in nature?
  • How can insects like pondskaters walk on water? [See picture] Or how can this lizard run on water?
  • Why can fish survive in a pond during the winter when the pond freezes over?
  • Water is a very good solvent.  This means it dissolves many substances.  What makes it so good as a solvent? 
  • Water is used to transport substances in our body.  Give the names of 2 liquids in our bodies that contain water, and say what they dissolve.
  • Why do we cool down when we sweat?

Useful revision stuff

Thursday, November 18th, 2010

Studying math by scui3asteveo on flickr

Click here for some revision notes on pathogens and the three lines of defense.  Immune system.

The first couple of pages of this site are good for variation and genetics review.  Variation.   Genetics.

Some information on leversMoments.  More information on the skeleton, joints and levers.