02.Chantelle+Attard

7/2/12 Robert Hooke & Robert Brown
 * Who were they?
 * What was their job?
 * What did they contribute to cell theory?
 * Why was their contribution so important?


 * Robert Hooke **

Robert Hooke was the first person to use the compound microscope to study and record cells in 1665. This gave him a greater advantage as he was able to see things closer with a compund microscope. He went to Oxford University to study art but was later on appointed as a geometry professor. Robert Hooke put thin cork under a compound microscope and discovered cells. He described that the cork looked as though it was 'filled with air and that air is perfectly enclosed in little boxes or cells distinct from one another’. The cork was made from plant material which means Robert Hooke was observing plant cells. Hooke's discovery is very important to cell theory.


 * Robert Brown **

Robert Brown was a scottish botanist who studied plants. He invented the microscope. He discovered Brownian motion in 1827 when he looked under a microscope to look at pollen grains in water. He found that water particles vibrate and are able to move, while bumping the pollen grains. Brown found that particles are constantly moving and bouncing off each other and other objects closer to them. He discovered and described the nucleus in plant cells. The discovery of Brownian motion is important because without it we would not know about the nucleus in plant cells.

7/3/12


 * **Organisation Level** || **Definition** || **Examples in plants** || **Examples in animals** ||
 * Cell || Building block that makes up all living things. || Palisade mesophyll cells, spongy mesophyll cells. || Muscle cells, brain cells, nervous cells. ||
 * Tissue || Similar cells all joined together. || Photosynthesis tissues, vascular tissues, || Muscle tissue, marbro tissues/ bone tissue. ||
 * Organ || Tissues joined together to complete a specific job. || Root, stem, leaf, flower, axillary bud, apical bud. || Brain, muscles, bones, lungs. ||
 * Organ System || A group of organs that work together to complete a specific job. || Photosynthesis, vascular system, mesophyll system. || Nervous system, skeletal system, respiratory system. ||

Root: absorbs water and minerals from the soil. Roots help to anchor the plant into the ground so that it doesn’t fall over or blow away. Roots also store nutrients for future use.

Stem: conducts water and nutrients from the roots in forms of glucose from leaves and other plant parts.

Axillary bud: develops at the axel of a leaf on a plant. Becomes a new stem or sometimes a floral bud.

Leaf: capture sunlight, which is used in the process of photosynthesis.

Flower: reproductive parts in plants. Contain pollen and ovules. Once the pollen has fertilized the ovule it develops into fruit.

Apical Bud: portions of meristematic tissue situated in the tip of the stem and shoots.

Photosynthetic tissue: uses light energy to fix carbon dioxide and produce carbohydrates.

Vascular tissue: the transport of water, ions, minerals and food.

Mesophyll tissue: material that makes up the majority of a plant's leaves. An extremely important organic compound.

Guard cells: help regulate the rate of transpiration by opening and closing the stomata which prevents water loss.

Epidermal cells: protective layers on the upper and lower sides of the leaf.

Palisade mesophyll cells: forms the bulk of a leaf, makes up the green tissue on the leaf and consists of thin-walled cells containing chloroplasts.

Spongy mesophyll cells: contains chloroplasts, which photosynthesise glucose. Holds air spaces for exchange of carbon dioxide and oxygen.

2/4/12 1. What are radioisotopes used for in medicine? Radioisotopes give doctors the ability to see inside the body and observe soft tissues and organs, in a manner similar to the way x-rays provide images of bones. Radioisotopes carried in the blood also allow doctors to detect clogged arteries or check the functioning of the circulatory system. 2. Provide 3 examples of a radioisotope and list where it is used. iodine 131 : provides diagnostic information. carbon 14: dating prehistoric findings. radiation: uses high-energy radiation to shrink tumors and kill cancer cells. 3. Choose one of your examples and describe the process.

4. List the pros and cons of using radioisotopes in medicine. pros: used as an advantage for treatment of diseases. cons: can sometimes have a negative impact/ side efffects.

8/5/12
 * Adaptations within an environment.**

Gambusia affinis, western mosquitofish Gambusia holbrooki, eastern mosquitofish
 * **What is its scientific name?**

Mosquitofish were introduced by military and local councils to control mosquito populations.
 * **Provide a diagram of the mosquito fish.**
 * **Why was the mosquito fish introduced?**

The mosquito fish has learnt to adapt to different water temperature. They prefer temperatures between 25°C and 38°C but have adapted to survive under ice and in temperature ranging up to 44°C. They can also tolerate a large range of salinities. They occur in clear and muddy waters, primarily in warm still or slow flowing water with surface vegetation.
 * **What are some of its adaptations.**

These strategies allow the mosquito fish to become highly competitive and widespread.
 * **For each adaptation, explain how it improves the mosquito fishes chance of survival?**
 * **What has this done to the how has this influenced the distribution and abundance of mosquito fish?**

12/6/12

The Urey & Miller experiment was conducted in 1952 by scientists Harold Urey and Stanley Miller. They created an early Earth's atmosphere containing reduced inorganic gases and lightening to realise how life on Earth began. 1953 was the landmark year for scientists that were researching the explanation of how life on Earth began. Miller announced that he'd had done an experiment which copied the early conditions on Earth and had reproduced the chemicals that were a necessity for life to begin. The production of organic substances like DNA base pairs(adenine) which may had triggered the first life form on earth. Amino Acids formed when electric sparks were crackled through a gas mixture. 13 out of these 22 Amino Acids created were used to make proteins in living cells.
 * What is the Urey & Miller experiment?**
 * Reasons for experiment:**
 * Results for experiment:**