03.Naiem+Botros

__ **Robert Hooke** __
__ Who is he? __ Robert Hooke was born on the 18th of July, 1635 and died on march 3rd, 1703 at the age of 67 . He attended Oxford University, he studied the theory of cells he was also a ph ysicist, biologist and an inventor.

__ What was he's job? __ Robert Hooke studied the theory of cells he was also a ph ysicist, biologist and an inventor, he invented the compound microscope in the 17th century

__ What did he contribute to cell theory? __ Robert Hooke put a piece of thing cork that was made from a tree under a compound microscope and discovered that cells have a nucleus in 1831.

__ Why was his contribution so important? __ He proved that all living organisms are made up of cells and discovered that cells are building blocks of all organisms.

= **__Robert Brown__** =

__ Who is he? __ Robert Brown was born in Montrose, Scotland on the 21st of December 1773, he died on June 10,1858 in London. He studied medicine in Aberdeen and Edinburgh before entering the British army an an ensign and assistant surgeon in 1795.

__What was his job?__

He was a botanist (a person who studies plants) and a plant geographer.

__ What did he contribute to cell theory? __ Robert Brown placed drops of water from a pond beneath a microscope and discovered the particles vibrating against each other. This is know as Browian motion. This the lead to Robert Brown discovery the nucleus in plant cells.

__ Why was his contribution so important? __ Robert Brown's contribution is so important because it helps scientists understand the format of cells more in depth.

=__cow and dog digestive system__=

__dog's digestive system__
**__ comparing the cow to the dog. __**

**__ similarity. __**

 * both the cow and dog have small intestine, large intestine and a e sophagus.

**__cow__**

 * a rumen
 * have
 * has four stomachs/chambers
 * doesn't have a caecum

**__dog__**

 * ** caecum (barely uses it) **
 * ** spleen **
 * pelvic bone
 * one stomach

=//**Radioisotopes and isotopes**//= = = // 1. What are radioisotopes used for in medicine? //
 * 1) Radioisotopes give doctors the ability to "look" inside the body and observe soft tissues and organs.
 * 2) allow doctors to detect clogged arteries or check the functioning of the circulatory system.
 * 3) detect problems within a body organ.

// 2. Provide 3 examples of a radioisotope and list where it is used. //
 * carbon-12
 * carbon-14
 * Deuteronomy

// 3. Choose one of your examples and describe the process. // Carbon-14 dating determines the age of certain archeological artifacts of a biological origin up to about 50,000 years old. It is used in dating things such as bone, cloth, wood.

// 4. List the pros and cons of using radioisotopes in medicine. //

=**__mosquito fish.__**=

__**scientific name.**__ Gambusia affinis

__**why was it introduced?**__ mosquito fish became well established and were widely dispersed by military and health authorities were used for malaria control.

__**adaptations and how it helps it survive.**__ Certain thermal adaptations have allowed them to live in places from 55° North to 44° South, expanding their natural range. They have a resistance to a wide variety of pollutants, including organic waste, heavy metals, insecticides, herbicides, rotenone, phenol, and radiation. Ichthyologists believe the reason for low mosquito levels in areas populated by gambusia is not because of the fish, but rather the insecticide in the water killing the larvae. Mosquitofish occur in clear and muddy waters, primarily in warm still or slow flowing water with surface vegetation. They prefer water temperatures between 25°C and 38°C, but have been known to survive under ice and in temperatures up to 44°C. Like Carp and Goldfish, the Mosquitofish can tolerate a wide range of salinities, all of these strategies allowing it to be highly competitive and widespread.

Currently, known populations of wild mosquitofish occur in every state and territory except the Northern Territory, and they are found in swamps, lakes, billabongs, thermal springs, salt lakes, and ornamental ponds.Mosquitofish have harmed native fish populations in many ways. By consuming algae-eating zooplankton, they increase the chances of algae blooms in the water, reducing the water quality. They are very aggressive, and tend to attack other fish and nip their fins, leading to infection or death. Mosquitofish have an extremely effective breeding strategy, being live bearers, out compete native fish especially in degraded systems and harass and nip the fins of other small fish and tadpoles. Mosquitofish has been implicated in the decline of several small native fish species. Mosquitofish are very aggressive and probably outcompete native fish for food and shelter. The decline of the soft spined rainbow fish in Queensland has been attributed to Mosquitofish. They may also prey on native fish eggs and fry.
 * __ What has this done to the ecosystem and how has this influenced the distribution and abundance of the mosquito fish? __**