biology‚ cell theory is a scientific theory that describes the properties of cells‚ which are the basic unit of structure in all organisms and also the basic unit of reproduction. The initial development of the theory‚ during the mid-17th century‚ was made possible by advances in microscopy; the study of cells is called cell biology. Cell theory is one of the foundations of biology.The observations of Hooke‚ Leeuwenhoek‚ Schleiden‚ Schwann‚ Virchow‚ and others led to the development of the cell theory
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roles of mitotic cell division‚ meiosis‚ and fertilization in the human life cycle. Mitosis allows for growth and repair from the fertilized egg to the adult. In reproductively mature individuals‚ meiosis creates gametes with half the genetic material. The male gamete then fertilizes the female gamete during sexual reproduction‚ forming a zygote with a full set of genetic material. 2. Why are both cell division and apoptosis necessary for the development of an organism? Cell division is needed
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The Dangers of Cell Phones Our community has increased greatly in technology during the past 20-30 years. Cell phones have given us more freedom and have also given us more freedom and have also given us the ability to communicate with anyone we want at anytime we choose. Cell phones‚ to some‚ are the greatest things invented to mankind‚ but every single thing must have a negative side. What is the negative side of cell phones? Cell phones are a horrible distraction‚ they are said to cause cancer
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Name: ______________________________________ Date: ________________________ Student Exploration: Osmosis Vocabulary: cell membrane‚ concentration‚ diffusion‚ dynamic equilibrium‚ osmosis‚ semipermeable membrane‚ solute‚ solvent Prior Knowledge Questions (Do these BEFORE using the Gizmo.) 1. Suppose you were trapped on a desert island with no sources of fresh water. Should you drink water from the ocean? Explain why or why not. _________________________________________________________________________
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also known as sickle cell disease affects the blood and cardiovascular system. There are six different types of SCD. The following discussion will include cause‚ symptoms‚ diagnosis‚ treatment and prevention. The proper education on this disease will give patients and the public a better knowledge of the common unfamiliarity with SCD. The cardiovascular system consists of the heart‚ arteries‚ capillaries‚ veins‚ and blood. The organs in the cardiovascular system are a vital part of the human body
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Cell’s July 18‚ 2011 Sickle cell anemia is an inherited blood disease that means you are born with it and it lasts a lifetime. People with sickle cell anemia inherit two variant or sickle cell genes‚ one from each parent. In the United States‚ sickle cell anemia affects about 72‚000 people. About 2 million Americans carry the sickle cell trait but about 1 in 12 African Americans have the trait. The signs and symptoms of sickle cell anemia are different in each person. Some people
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SPECIALIZED CELL ANIMAL Sperm cells PLANT Xylem cells are specialised to find a female cell (egg cells) and join with it. They have tails‚ that makes them move in water to find and fertilize the female cell. They can move because they have many mitochondria located between the tail and the head‚ which gives them energy. In the head‚ there is a vacuole filled with acrosome‚ which is a specialized Lysosome that releases enzymes in order for the Sperm Cell to break into the Egg Cell‚ through the
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ROD CELLS Rod cells‚ or rods‚ are photoreceptor cells in the retina of the eye that can function in less intense light than the other type of visual photoreceptor‚ cone cells. Rods are concentrated at the outer edges of the retina and are used in peripheral vision. On average‚ there are approximately 125 million rod cells in the human retina.[1] More sensitive than cone cells‚ rod cells are almost entirely responsible for night vision. STRUCTURE AND FUNCTION Rods are a little longer and leaner
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- The major functions of the cell is concentrated at the outer edges of the retina and are used in peripheral vision. On average‚ there are about 125 million rod cells in the human retina. Rod cells are almost entirely responsible for night vision. Rod cells do not process fine details or color differences‚ but are highly sensitive to light. A single flash of light is all that is require to produce a response from a rod cell. Rod cells function as specialized neurons that convert visual stimuli in
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can continue to prosper. The planet Aedan has been chosen to form a new Earth. The inhabitants of this planet must be destroyed before the human race can prosper once more. One of the beings from Aedan has now been captured. This is her story. 2. int. Outside of Cell. Day A masked scientist (scientist 1) stands in front of a door. The camera pans from right to left across the scientist’s masked face. Being (V.O.) This is how my days begin... The
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