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Theories on the origin of life 200 words
Theories on the origin of life 200 words
Theories on the origin of life 200 words
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Recommended: Theories on the origin of life 200 words
Allison Yi 1/19/17
AP BIO Section number 132
Theories for the Origin of Life on Earth
1. The Panspermia theory is a theory that suggests that life on Earth started due to a meteorite colliding to Earth and that life did not start on Earth. The theory explains that life was existent in space and that there was a bacteria that was able to travel in space in a meteorite.
2. A. The Chemical evolution theory states that early earth conditions were very harsh. For example, Earth was very hot and the atmosphere consisted of mostly water vapor, carbon dioxide, methane and more. However, oxygen was not in early Earth and no ozone layer was present therefore, the UV rays were
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A. The formation of eukaryotic cells and its nucleus and organelles occurred due to more complex life. The infolding of the cell membrane created the nucleus and endomembrane system. The organelles formed were the golgi bodies, vesicles, plasma membrane and the endoplasmic reticulum.
B.The organelles formed were golgi bodies, vesicles, plasma membrane and the endoplasmic reticulum and are known as the endomembrane system. The evidence for their origin is supported through the cell membrane infolding because these structures are connected together. In addition their functions depend on each other. This can be explained by the endoplasmic reticulum producing proteins or lipids. This then enters the vesicles which usually omr when secretion is happening. Next, to the golgi bodies which help secrete and help intramolecular transport. This then goes to the plasma membrane which determines which things are let in or out of the cell. From the plasma membrane, the products are let out of the cell.
5. A. The mitochondria was thought to have been an aerobic prokaryotic cell. This aerobic prokaryotic cell should be small as it is ingested by a larger host cell.
B. The chloroplasts were have thought to have been a photoautotrophic cyanobacteria. This would have to be small because it is ingested by a larger host
Question 1: Briefly describe, in 500 words or less, the normal structure and function of your chosen cell type. In your answer, discuss specific features in your chosen cell type, including cell organelles.
There are many different cells that do many different things. But all of these cells fall into two categories: prokaryotic and eukaryotic cells. Eukaryotic cells contain a nucleus and are larger in size than prokaryotic cells. Prokaryotic cells do not contain a nucleus, are smaller and simpler than eukaryotic cells. Two of their similarities are they both have DNA as their genetic material and are covered by a cell membrane. Two main differences between these two cells are age and structure. It is believed that prokaryotic cells were the first forms on earth. They are considered primitive and originated approximately 3.5 billion years ago. Eukaryotic cells have only been around for about a billion years. There is strong evidence that suggests eukaryotic cells may be evolved from groups of prokaryotic cells that became interdependent on each other (Phenotypic analysis. (n.d.).
Eukaryotic Cells are Deemed as a Result of the Evolution of Symbiotic Prokaryotes Both Prokaryotic and Eukaryotic cells over time have sustained very dynamic changes from one another. More specifically we have seen the appearance of a more complicated and organized cell structure, the nucleus. However the big question amongst scientists today is how did these changes first occur? A fundamental concept of this evolution is the belief in the natural progression 'from the simple, to the more complex.' However one popular theory that argues that Prokaryotic symbiosis was responsible for forming the Eukaryotic nucleus is the 'Endosymbiotic Theory' this theory was first proposed by a former Boston University Biologist known as Lynn Margulis in the 1960's.
Lane’s argument is greatly over-simplified and his opinion implies that mitochondria are the sole answer to the mystery of complex life. To reiterate, Lane does provide a compelling argument in favour of the role of mitochondria and how they assisted the formation of complex life, but to say that that is the only reason would simply be false. There is a vast amount of other reasons why eukaryotic cells came to be and why they ended up thriving in their environment. This particular section of the book was much more fascinating to read than the previous
Hello everyone. Today for my speaking assignment, I will be speaking to you all about the mitochondrion because I don’t know what else to talk about. For the first part, I am just going to summarize what I know and won’t be going in depth with it as much. Anyways, as most people know, the mitochondrion is the powerhouse of the cell. Mitochondrion is singular while the plural version is mitochondria, which is the one people tend to say and it’s not wrong either way. It is an organelle found in most eukaryotic cells. In 1890, it was discovered by German pathologist Richard Altmann and was called “bioblast” at the time. People also were very skeptical at the time about his findings of the granules and even harshly criticized Altmann until the
Evolution theories have been around for a long time. There have also been a lot of old- and young Earth creationism arguments. These theories and arguments are discussed in this paper.
The mitochondria are sausage-shaped structures that move, change their shape and divide. They are distinct organelles with two membranes, the inner membrane and the outer membrane. The outer membrane is smooth and limits the organelle. It is highly permeable to small solutes such as molecules and ions, but it blocks off passages of proteins and other macromolecules.
The nucleus is one of the most important organelles in a eukaryotic cell. The shape of the nucleus is generally spherical, it should be oval, disc formed reckoning on the sort of cell. The nucleus was found by Robert Brown in 1831 while he was looking at orchids under a microscope. He discovered a blurred area in the cells of the flowers and called it the areola or the nucleus.
The theory of evolution, as set forth by Charles Darwin in 1859, stated that all plant and animal life evolved over long periods of time from simple to more complicated forms through mutation and adaptation. He also taught that only the fittest of each species would survive. He further postulated that the first living cell evolved in a "warm warm little pond" and that it took billions of years for the present diversity of living things to evolve. At the time, it was thought that the few "missing links" in the fossil record would be soon filled.(Darwin, 1927 ). Today, however, there is today a considerable body of scientific evidence that refutes this entire theory.
The mitochondria is an organelle which is generally an oval shape and is found inside the cytoplasm and is again apart of the eukaryotic cells. The main function of the mitochondria is to complete cellular respiration; in simple terms it acts like a digestive system to break down essential nutrients and to convert it into energy. This energy is usually found to in ATP which is a rich molecule taken from the energy stored in food. Furthermore, mitochondria stores calcium for signalling activities; such as heat, growth and death. They have two unique membranes and mitochondria isn’t found in human cells like the red blood cells yet liver and muscle cells are filled entirely with mitochondria.
Charles Darwin proposed the theory of evolution to explain the origin, diversity and complexity of life. I will will disprove evolution by showing that natural selection only explains small evolutionary changes, collectively known as microevolution. Natural selection cannot drive large evolutionary changes, macroevolution. I will also show that the primordial soup, in which life supposedly evolved, did not exist.
In this cell though, the nucleus was not present. The plant cells and animal cells were very different. In the plant cells there was motion of cell parts but in the animal cells there was no motion. Also, the nucleus and chloroplast of the plant cell were towards the outside of the cell because the chloroplast can receive sunlight better on the outside of the cell than on the inside. In the animal cells though, the nucleus and cell organelles, were towards the middle of the cell.
Mitochondria are small granular or filamentous bodies which are called the power house of the cell. They are associated with cellular respiration and are the sources of energy. In 1850, the German biologist Rudolph Kolliker first observed mitochondria as granular structures in striated muscle [Powar, C.B. 2010; Albert et al. 2010]. In 1898, the scientist Benda developed the crystal violet staining technique and called the structures mitochondria. The average length of the mitochondrion is 3-4 microns and the average diameter 0.5 to 1.0 micron. In muscles, most of the mitochondria are 2-3 microns long. Mitochondria have different shapes. The number of mitochondria is different in different types of cells of different organs. They are distributed evenly in the cytoplasm. In sperms they are present in tail, in muscles they lie between the myofibrils. Mitochondria may move freely in some cells. Where ever ATP required. Movement is less in animals than plants. In plants they change their shape and volume [Powar, C.B. 2010; Albert et al. 2010].
This organelle is the site of photosynthesis in plants and other organisms. In the structure, the chloroplasts has a double membrane, the outer membrane has a continuous boundary. This organelle can be found in a vast group of organelles called the plastid, chloroplasts are usually found in many plant cells but never in animal cells. Chloroplasts organelles are large; they are 4-10um long and 2-3um wide. They are very important to plants because chloroplasts are what plants use to create food from sunlight. Chloroplasts are not found in humans.
One argument that supports the panspermia theory is the emergence of life soon after the heavy bombardment period of earth, between 4 and 3.8 billion years ago. During this period, researchers believe the Earth endured an extended and very powerful series of meteor showers. However, the earliest evidence for life on Earth suggests it was present some 3.83 billi...