The correct option is A.
The nature is organized in such a way that, one organism's waste is what the other organism will use as its own resources. For instance, during the process of photosynthesis, the oxygen that is produced as the by product of the photosynthesis process is what humans use to carry out their own breathing process.
Why did the narrator use the phrase “fit together like puzzle pieces” to describe how the cells of a developing human embryo form a human face
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the Cell Theory was give by German scientists, Schleiden and T.Shwan in 1839. It stated that,
- All organism are composed of one or more cells
- The cell is the structural and functional unit of life
- It is a de novo structure, that means it COULD arise from non living thing which was incorrect.
It was corrected by the German pathologist Rudolf Virchow in 1855. He made a convincing case, corrected and added the third point of the cell theory. It is,
- Cells can arise only by a division of pre-existing cell. It is <u>NOT</u> a de novo structure.
Cell theory brought a great evolution in the field of biology which established the function of organism is the result of activities and interaction of the cell units.
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- <u>Flask 1</u>: It is observed that there are no micro-organism, this is because the meat is sealed and no micro-organism could enter through it.
- <u>Flask 2</u>: It is observed that there are micro-organism present because meat is not sealed but open.
- <u>Flask 3</u>: As the S tube is used, the micro-organism are not able to reach the meat because of the curvy path
These observations support the point that<u> cells could arise only by a division of pre-existing alive cells</u> because in Flask 1 when there were no micro-organism present so there was no organisms found so no micro-organism arised, In flask 3 the S tube was used so no micro-organism could reach the meat thus there were no organism there which could divide to reproduce. The flask 2 was open, so the micro organisms reached the meat so they divided which means Cells can only arise by a division of pre-existing cells.
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Smooth muscle, also called involuntary muscle, muscle that shows no cross stripes under microscopic magnification. It consists of narrow spindle-shaped cells with a single, centrally located nucleus. Smooth muscle tissue, unlike striated muscle, contracts slowly and automatically.
Yes, if the immune system is strong, it is capable of fight off an illness with the help of the white blood cells (leukocytes). They act as the "soldiers" of the body because they are the first ones to try and kill whatever illness affects the body. Unless the person has a weak immune system, which can be a cause from poor health.