Microbes revision

Here are the main points that you should be comfortable with for the test on monday:
Q1. People still die from infections for several reasons - They might not have access to medicine, the pathogens might be resistant to the medicine, or their bodies' defences might not work as they should (skin, stomach acid, immune system).
Q2. The celebrity could pick up an infection in several ways - eating or drinking contaminated food, being bitten by insects, from animals like mice or rats, from other people (coughing etc.) or by cutting hersef as in question 3.
Q3. Macrophages try to engulf the bacteria, if they don't succeed white blood cells try engulfing the bacteria and then exploding, and finally antibodies can join to the outside of the bacteria (with the antiibody joining to the antigen).
Q4. b, d, a, e, c.
Q5.
a. Some rabbits live in a field.  This is their habitat.
b. A stream flows through a field and many species live there.  The living things and their enivronment from an ecosystem.
c. Lots of different species live in the field so it has a high biodiversity.
d. The total mass of living things there is the biomass.

Q6. Grass, grasshopper, snake owl.
Grass is the producer.
Snake and grasshopper OR owl and snake.

Q7. a. More pike will cause the number of perch to decrease.
       b. The pike would eat the perch, which would leave less for the heron so they wouldn't visit the pond as  much.

Key points:
Make sure youre happy with the four types  of microbes we've looked at - bacteria fungi, viruses, protozoa.  Knowing some good and bad things they can do would also be useful.

Understand the different steps in our bodies fighting microbes - skin, stomach acid, and the immune system (which also has three parts - macrophages, white blood cells and antibodies).

Know how food chains/webs work and how to make predictions using them.  Make sure you can draw them with the arrows going from the PREY to the PREDATOR.

Understand what biomass pyramids represent, and what a normal one looks like.

Good luck!

Food webs

We will be looking at food webs today, continuing on from what we started last lesson.  Use the links below to help you answer the following questions:

1. Complete the food web activity on this link - http://www.gould.edu.au/foodwebs/antarctic.htm .  Click on the answer image once you're done to help you with the next questions.
2. Name three different animals in the antarctic food web.
3. What gets the energy from the sun for the Antarctic food web?  What are organisms that do this called?
4. Which way do the arrows always go in food webs/chains (from what to what)?
5. Imagine that there were more Emperor penguins born in a certain year by chance.  List five other animals this would affect, and whether their numbers would increase or decrease.
6. What is the difference between phytoplankton and zooplankton? Name one similarity as well.
7. How many animals would be affected if phytoplankton became less common?
8. Find out what a 'keystone species' is and give a definition in your book

http://www.coolantarctica.com/Antarctica%20fact%20file/wildlife/whales/food%20web.htm -  Information on the types of animals and a good diagram of the  antarctic food web.


Complete this crossword once you've finished the questions - http://www.ntscience.co.uk/science-crossword/7c-environment3j.html


One last activity, highest score will get an achievement point! - http://puzzling.caret.cam.ac.uk/game.php?game=foodchain

For this lesson, try and answer the following questions in your books.  Use the internet to help you, there are several links below that may help.

1. What are three problems/diseases that bacteria can cause for humans?
2. Where might you find the bacteria vibrio cholerae?
3. Define the word pathogens:
4. How can people stop the spread of pathogens?
5. Why do you think that microbes like bacteria and protozoa have only been discovered since the microscope was invented?
6. How do protozoa move?

Talking about the microscope: http://www.typesofbacteria.co.uk/how-when-were-bacteria-discovered.html
BItesize site with lots of information about microbes: http://www.bbc.co.uk/schools/ks3bitesize/science/organisms_behaviour_health/disease/revise1.shtml
Have a go at the games on this site once you're finished:
http://www.themicrobiologyblog.com/2010/05/microbiology-games.html, or this one: http://armorgames.com/play/2258/microbe-kombat
http://en.yupis.org/microbe-games/

nviz revision

Here are the answers to the revision sheet if you want to check yours:

Q1. television - d
       Speakers - b
       Spark - e
       Digger - c
       Kettle - a

Q2. a-If the television were more efficient, less heat would be produced as this is wasted energy.
       b-Energy going in, coming out as sound and heat.  Something like the picture below but with sound and heat labelled instead of 'useful work' and 'heating the surroundings.'

Q3. The atmosphere is a layer of gases which surrounds the earth.  By produing more carbon dioxide and releasing it into the atmosphere, we allow the Earth to warm up.  This is called the greenhouse effect and leads to global warming and climate change.
Q4. Renewable energy sources, such as solar, wind and hydroelectric power produce no carbon dioxide while producing electricity.  This will decrease the rate of climate change and prepare us for wen fossil fuels run out.
Q5. Wind and solar power only provide electricity when it is sunny or windy.  This means that they can not be available at times when they are needed.  To fix this this problem, either a battery to store power is needed, or another renewable energy source that provides constant energy, like geothermal or hydroelectric power.
Q6.  Climate change may cause Sea levels to rise, Ocean acidification, increased frequency and severity of extreme weather (storms, hurricanes), droughts, diseases and food shortages.  These problems could lead to many social and other problems.

I.T. lesson

Copy this address into another tab: http://www.fife-education.org.uk/energy/curricular_links/simenergy2.htm
Click on 'try the game' and play a few times so you get used to how it works.  Try and make the most money from the month! Once you've had a go answer these questions:
1. Which renewables provide the same amount of power all the time?

2. Why is it important to investigate before putting in a renewable energy source?

3. When during the day is the family's power useage the highest?

4. What do you need to be able to store the power generated at other times during the day?

Once you have finished that, have a look at these two articles:

http://news.bbc.co.uk/1/hi/england/oxfordshire/8210840.stm

http://www.oxfordtimes.co.uk/forum/letters/8956976.Too_many_turbines/

The first one talks about a plan for more wind generators in Oxford, and lists several reasons why they might be a good idea.  The second one is a letter written by someone opposed to them.  Read both articles, and write your opinions in your book. 

Computer lesson

As we're almost finished the unit on climate change (nviz), we'll be going to a computer room next week to do another activity on renewable energy as we started last week.  Make sure you come to class on time so we get as much time as possible on the computers!

This is the video that we ran out of time for today, if you want to do some more revision see if you can work out if it is exo or endothermic and why.

Keypoints

These are the five points that you should know for the test tomorrow, along with some sample anwers:  Remember that they're also on the back of the sheet from todays class, and that the other revision sheet will help you:
The difference between elements, molecules and compounds.

What the reactivity series can be used for:

What the three sides of the fire triangle are:

What exo and endothermic reactions are:

How to test for acids and bases:

1. An element is one type of chemical, a molecule is two or more atoms of one element bonded together and a compound is two or more different elements bonded together.

     2. The reactivity series can be used to predict the products in a reaction.
     3. The three sides of the fire triangle are heat, fuel and oxygen.  Without all three, you can't start a fire(also called a combustion reaction).
     4. Exothermic reactions give out heat (like a match burning) and release energy.  Endothermic reactions take in heat (like an ice cube melting) and require energy. 
     5. Acids and alkalis can be tested using Universal Indicator.  Acids (pH from 1-6) turn red if they are strong or orange/yellow if they're weak, while alkalis (pH 8-14) turn purple if theyre strong and blue if theyre weak.  Neutral things (pH 7) turn green. 

Acid/Alkali homework

Here is the link to the slideshow from today - try the questions and bring them in tomorrow for an achievement point! https://docs.google.com/present/edit?id=0ATFUvVu_WNI_ZGRxdDk3a3hfOTVmamt4anBnMg&hl=en

Here is a video of the reaction we saw in class today, try and remember why this reaction is important to us!

Here is the link to the oxidation slideshow we used today - https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0BzFUvVu_WNI_ZWUzZGQ0NDQtOGRlNC00YWM4LWFmNjAtODAzZmMzM2Y1NjQ3&hl=en Make sure that youre familiar with the keypoints on the last slide as we will be doing another practical relating to these later in the week.

Copper and Iron

Our second displacement reaction went well today, make sure you remember how they work for tomorrow as we will be looking at something called the reactivity series in relation to them.  If you have time, try and remember as many chemical symbols as you can from your planner

Displacement reaction

Cu + 2AgNO₃ = Cu(NO₃)₂ + 2Ag

This is the reaction that we looked at in class during the practical today.  Make sure you remember which parts are compounds and elements and how they swap over.  We will be doing another practical tomorrow so looking at the periodic table and knowing the symbols for Iron and Copper would be useful.

Hi Year 8, this is the link to the crossword that we started in class on Friday.  Knowing all the answers will help you to understand the practicals we will be doing this week. https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0BzFUvVu_WNI_NmE1NGZmMDUtY2MyZi00ODQ2LWIxMzEtMzEwYTg3NmQ4Mjgw&hl=en

week 1

Here is the video on thermite we saw in class this week, and this is the link for the crossword on elements and compounds that we started:
https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0BzFUvVu_WNI_NmE1NGZmMDUtY2MyZi00ODQ2LWIxMzEtMzEwYTg3NmQ4Mjgw&hl=en

Next week we will start some practicals, but try and finish the crossword and remember as many element symbols as you can.

video

Watch this video and see if you can identify what the three sides of the fire triangle are.

This diagram shows the three things that you need to create a fire (or a firework). If you only have one or two of the three sides you wont have a fire.  Make sure you remember this for future lessons.

Welcome!

Hello Year 8, this is our class blog where I will post material to help you with the course.  Either save the address to your favourites or make sure you have it somewhere safe so you can check in regularly.  As the background suggests, we are going to be studying PYROTECHNICS after half term