Untitled Storyboard
Текст на Статията
- Пързалка: 1
- Ooo yes! That in fact is an Asian Mallard. It is the practically ancestor to all ducks!
- Hey Grandpa! I see a duck!
- Пързалка: 2
- Alrighty! Well first off, this duck started off as a little tiny cell. chromatin turns into chromosomes, and the nuclear membrane breaks down which causes for the spindle fibers to form.
- Tell me more!!
- Пързалка: 3
- Then, chromosomes start to line up in the cell, and they are attached to the spindle fibers.
- Wow... then what happens?
- Пързалка: 4
- Well, certain chromatids called "Sister chromatids" are pulled apart to opposite ends of the cell. The nuclear membranes reform around the sets of chromosomes, which begin to unwind back into chromatin.
- The duck keeps looking at me!
- Пързалка: 5
- The cytoplasm then divides, resulting in two separate daughter cells!
- Thats really cool grandpa! I have a question. Why do cells divide?
- Пързалка: 6
- Good question Mariah. Cells divide for a number of reasons. Two of them being-- whenever you get a small cut, or a bruise, cells divide to replace those hurt and broken cells. They also divide to help you and other organisms grow!
- Oh! Okay. But what happens if they divide uncontrollably?
- Пързалка: 7
- Well, if cells divide uncontrollably, that results in a Cancer. Cancer is when cells in your body grown nonstop, which is not normal.
- Oh man... that sucks! But wait... where does the first cell come from?
- Пързалка: 8
- Cells form from a process called, Meiosis. 2 adults, do their thing which causes for the sperm, and the egg to collide. The homologous pairs align at the cells equatorial plate.
- Mhm... okay then what?
- Пързалка: 9
- Then, the homologous chromosomes are pulled apart to opposite ends of the cell and the cell divides into two cells, each with half the original number of chromosomes.
- mhm.. i dont understand.
- The chromosomes condense, and a spindle forms in each cell. The chromosomes align in each cell and the sister chromatids are pulled apart to opposite ends. Lastly, the Nuclear membranes reform, resulting in 4 haploid daughter cells!
- Пързалка: 10
- Thats a great question. It is because, when the cells are produced by cell division, they get a copy of DNA, or all the chromosomes it has in it's nucleus.
- Wow I kinda get it. One more question Grandpa, how does cell division allow for each cell to stay identical?
- Wowww thats really cool! It's like they have a memory card!-- oh and look! there's more ducks!!
- Yes Mariah, Yes it is! We just discussed the processes of Mitosis and Meiosis. Let's go feed the ducks!
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