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3 reasons cells need to divideReason Why
Growth An individual cell cannot grow very large so it has to split into two cells with the same function
Repair
Reproduction
3 reasons cells need to divideReason Why
Growth An individual cell cannot grow very large so it has to split into two cells with the same function
Repair Cells don’t live as long as we do. We need to replace cells that die.
Reproduction
3 reasons cells need to divideReason Why
Growth An individual cell cannot grow very large so it has to split into two cells with the same function
Repair Cells don’t live as long as we do. We need to replace cells that die.
Reproduction Organisms made of one cell need to divide to make new organisms
Cell structures needed for cell division
• Nucleus: The control center of the cell- It directs cell division
- Contents of the nucleus for cell division
Cell structures needed for cell division
• Nucleus: The control center of the cell- It directs cell division
- Contents of the nucleus for cell division- Chromosomes: The material that directs all the
activities of the cell.- Made of DNA (deoxyribonucleic acid)
- Nucleolus: Makes the ribosomes and ships them out to the cell.
What is DNA made of?
• The structure of DNA looks like a twisted ladder. – The sides of the ladder are made from sugar-
phosphate chains– The steps of the ladder are made from two of the
four nitrogenous bases• Adenine • Cytosine • Thymine• Guanine
DNA Replication
• Before a cell divides it needs to make sure it has two copies of DNA. To make this copy it unzips and new pieces ofDNA fill in the other sides