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Here is where i will post all the original word documents incase of them being hard to read on the blogger

Microbes and Food and Preserving Food 17.2

17.2 Preserving Food

1) You are writing a recipe for bottling fruit. Which stages would you stress to make sure that the fruit would keep well?

I would stress closing the container and refridgeration.

2) Why can dried fruit be kept for much longer than fresh fruit?

Moisture is what bacteria can live on, and when something is dried, it needs a while to retain moisture again, taking longer time to spoil.

3) ‘Steak tartare’ (minced steak mixed with egg yolk) is eaten raw.

a) What are the dangers of eating raw meat and eggs?

Raw foods are prone to bacteria, while cooking can actually kill bacteria.

b) Which of the above methods could be used to kill the bacteria in the meat? (Heating isn’t allowed!)

Irradiation is probably the most useful method in such a case.

4) Chickens and turkey contain salmonella bacteria

a) Do frozen chickens and turkeys contain these bacteria?

Yes they do, because freezing does not kill bacteria, it merely slows its growth.

b) Why is it important to let the bird thaw out completely before cooking it?

If you don’t completely thaw out the bird, the inside will remain raw after cooking, so the chicken will have microbes on the inside still.

5) Why is it dangerous to thaw frozen meat and then refreeze it without cooking?

When food is completely unfrozen, dangerous bacteria can begin to [quickly] grow on it, and because a freezer does not kill bacteria, if you unfreeze meet then refreeze it again, there is still danger of bacteria being there.

17.2 Microbes and Food

1) List the main types of microbe and their effects.

a. Fungi (important in eating)

b. Bacteria (can help you with vital processes, can make you sick)

c. Algae (provide a lot of the oxygen we breathe)

d. Viruses (Make you sick)

e. Protozoa (feed on material, decompose)

2) Make a list of foods which use fungi in their production. Try to find out others not mentioned here.

1. Artificial Citric Acid

2. Vitamins

3. Soy sauce

4. Processed meat products

3) Name a fungus you can eat which isn’t a microbe

Mushroom

4) What would be an alternative way of producing bubbles in bread

Pumping oxygen in manually, but that would be very painstaking.

5) Try to find out other types of food which use bacteria in their production

1. Butter

2. MSG (monosodium glutamate)

3. Alcoholic drinks

4. Kefir

Studying Animal and Plant Cells Homework

Studying Animal and Plant Cells

Animal Cells

1) Fat cells and muscle cells

2) Egg-ish or circular

3) A: nucleus B: cell membrane C: cytoplasm

Parts of animal cell	Role(s)
Nucleus	The control center, it gives information on what type of cell is formed
Cell membrane	An outer delicate layer that contains the contents of the cell and allows substances to enter and leave
Cytoplasm	Jelly-like liquid where cell activity occurs

4)

5) No I do not think the nucleus must always be in the middle of the cell. Plant cells do not have the nucleus in the middle

6) Animals cells have no cell wall, while a plant cell does, keeping everything contained inside

Plant Cells

1) The plant cell is rectangular

2) A root cell

3) Cytoplasms, cell membranes and nuclei are found in both plant and animal cells

4) Cell vacuoles, cell walls and chloroplasts are found only in plant cells

Part of Plant Cell	Role(s)
Cell wall	An outer protective layer that keeps the cell rigid
Chloroplast	A structure that contains green pigment that traps light
Cell vacuole	A fluid-filled space inside the cell that gives the cell its shape.

5)

note, that although i will publish all homeworks here, i will always post a link to the original file, in case there are any mistakes. here is the link to the original file: http://15htk1.qataracademy.wikispaces.net/file/view/Studying+Animal+and+Plant+Cells.docx

Plant and Animal Brainpop Homework

Plant and Animal Cells: Differences and Similarities

Animal cell are made of a nucleus, a cytoplasm, organelles (little parts that are like the different organs of a cell) and cell membrane. While plant cell may have all these, plant cells also have a cell wall which is a rigid sort of outer coating that helps maintain the cell’s shape. Plant cells also have chloroplasts, which only plant cells need for photosynthesis.

Bacteria

Bacteria are single celled organisms that are everywhere. They are everywhere you go, and to remove bacteria from something is call sterilization. Bacteria have a role in many things. For example, bacteria are in our digestive tract, and they help us digest things we normally wouldn’t be able to digest. Plants need bacteria as well, as they convert nitrogen in the soil to simpler forms that plants are able to absorb. The downside of bacteria is that some of them are bad, for example, they are responsible for many know diseases, and they are not always on our side. Bacteria are different from other types of cells, they are prokaryotic, which means that their nuclear material is not surrounded by a membrane.

Pictures of Different Cells

Animal Cell

Plant Cell

Links to original files:

As with always (and because the pictures are cut off), i will post individual links to the original files
Write Up (with similarities and differences): http://15htk1.qataracademy.wikispaces.net/file/view/Plant+and+Animal+Cells.docx
Animal Cell Picture: http://15htk1.qataracademy.wikispaces.net/file/view/Animal_Cell.jpg
Plant Cell Picture: http://15htk1.qataracademy.wikispaces.net/file/view/Plant_Cell.jpg

Microbes Homework

Go to websites:

http://www.microbeworld.org/index.php?option=com_content&view=article&id=46&Itemid=55

http://www.microbeworld.org/index.php?option=com_content&view=article&id=87&Itemid=59

Answer each question in your notebook.

1. Write a short introductory paragraph for this topic

Microbes are tiny unseen forms of life that are only single celled. They are vital to us, and we need them for many essential processes such as eating or breathing, and without us, they’d probably be fine, they were even alive with and before the dinosaurs and fossils date back to as far as 3.5 billion years.

2. What is the term microbe used for?

The term microbes is used to describe small single celled organisms which are vital in the lives of humans, as many of them are useful and help us live. They are also too small to be seen by the naked eye.

3. List the five types of microbes.

Bacteria, fungi, algae, protozoa and viruses

4. Draw and colour some microbes.

5. If you enlarged the smallest microbe, a virus to the size of a baseball, how big would the other microbes be in comparison? Draw and colour some diagrams to explain your answer.

Virus bacterium human cell

6. What features do microbes have that make them successful?

They are small and can reproduce quickly. They are also very basic and can survive in many different environments.

7. From the microbes in the news file choose two articles and explain each one briefly.

pictures did not show up clearly, but you can find the original document at http://15htk1.qataracademy.wikispaces.net/file/view/MICROBES.docx

Introduction

Hey, everybody. This is my Science blog, where i will electronically submit my homework.